Speculative Biology: Chase for a Blue Chimera

When in book or web pages squids of the far future develop land habitats, rabbits turn to long-legged counterparts of antelopes, and giant descendants of zebra parakeets run across terraformed Mars, we most likely are dealing with the product related to a special literary movement named as “speculative biology”. It is a special genre of fiction, which has emerged at the boundary between science fiction and principles of biology. Unfortunately, in Russian literature it is rather rare, whereas in the countries of Western Europe and USA many books of this direction got popularity and having significant number of admirers are already published. In our time, when electronic technologies have penetrated into all areas of life and every interested person can create his/her own information resource, in Internet numerous projects of this type had been created – mainly in foreign languages, however some speculative biological projects in Russian language exist now also. Maybe, this genre is not as popular now, as hard science fiction or fantasy, but it has its own army of admirers and authors creating new projects.
The purpose of the present issue is the general review of features of the present literary genre and of opportunities of its application to various fields of human activity. Despite of its unreality, speculative biology is also open to be used for the solving of some practical problems. The final part of the present review is dedicated specifically to that subject.

I. What are we talking about?

Before the beginning of the talking on speculative biology, it is necessary to tell precisely, what that is.
If we shall start to analyze a certain project from the field of speculative biology, we’ll necessary face more or less detailed descriptions of live creatures and ecosystems which they form. We can learn about features of their appearance, biology, phylogenetic relations. Descriptions may be detailed and even faultless from the scientific point of view. However, can speculative biology be taken for a science? Alas, it is impossible. In addition, differences between “common” and speculative biology are principal, resembling the deepest abyss.
Science has for an object the studying of the world around. Theories and concepts proposed for its explanation permit to isolate verifiable facts from objective reality. They also – in ideal conditions – determine which facts and in what way are capable to falsify them. Speculative biology is guided by theoretical base of biology and other natural sciences and transfers it to another factual basis, which is, however, partly or completely a product of author’s imagination. Thus, it is a science which subject of studying is invented, but not by other people (in sociology such situation is common), but directly by author-researcher. Thus criticism, verification and falsification do not disappear anywhere; they are quite present, either in discussion inside the collective of authors, or in comments of readers.
This is not to say that such approach is completely alien to “conventional” science. It includes great fields which subject of studying is completely fictitious – for example, search of extraterrestrial civilizations or research of global catastrophes*. Here even mathematical “formulas of non-knowledge” exist, such as well-known Drake’s formula. However all these areas have justification: they operate with purely invented concepts, because the objective data on their domains are not received yet and, maybe, will not be received forever. There is a different situation in biology: it has hands full of further work, and “serious” researchers are disinclined to fritter away their efforts for speculations.
As objects and situations which speculative biology operates are obviously not observed in the real world and are not accessible for studying by scientific methods, we had to recognize it exclusively as a current of fiction. There is one good reason for this step. A key element of fantastic piece is a certain fantastic assumption, which is not observable in real world. For a genre of speculative biology, such assumption is a fantastic situation in which we make real biological processes and the phenomena to work. It may be a world of the future on the Earth, alternative development of events of the past, or a nature of other planet at all. In this case, an indispensable condition however is strict consistency of the described invented world, phenomenon or a creature with scientific evidence.
However, the wall between speculative biology and natural sciences is not insuperable. Numerous arising or boundary fields of science (like search of extraterrestrial life or cryptozoology) have so vague representation about their subject that at first they are compelled to determine for themselves, what actually they are going to search. Here again groundwork of speculative biology appears quite pertinent. It is no accident that in the course of recent years in serious educational and even purely scientific magazines articles** related rather to the genre in focus begin to appear.
Summarizing the above, the following features of speculative biology as a genre can be highlighted:
1) The main theme of the work is related to biology and evolution. This feature separates speculative biology from fictional works, where fictional worlds serve only as a background for the development of the plot not related to biology.
2) The creatures in focus are fictional. These can be clearly fanciful and other fictional creatures (for example, mermaids or dragons, as well as snouters), representatives of evolutionary lines that have not left a trace in the fossil record and therefore unknown to science (for example, Antarctic dinosaurs), the result of alternative evolution (dinosaurs of the Cenozoic era, intelligent dinosauroid) or living beings of the future, more often the Earth after the extinction of mankind. A reservation should also be made here in relation to real living organisms that inhabited the Earth in the past. If we are talking about features that leave no sign as fossils and therefore are not confirmed by science (behavior, coloration and soft tissues), then these are also issues for speculative biology.
3) The approach to the description of these creatures is strictly scientific, referring to the maximum extent to modern knowledge of biology and related disciplines. In this case, the design of fictional creatures is based on the physiological capabilities of the organism, and the choice of an ancestor for living organisms of the future is based on estimates of trends in the evolution of modern living organisms.
Therefore, beginning the travel in the wonderful world of speculative biology, we shall remember that every fair and consecutive reflection made with sincere intentions will not go to waste. And let’s have this remarkable citation from Stanislav Lem’s book as a beacon:

* См. Турчин А.В. «Структура глобальной катастрофы: Риски вымирания человечества в XXI веке». М.: URSS. 2011. 432 с. (in Russian)
** См. Цзян Н. «Цвет растений на других планетах» / «В мире науки», №7, 2008; Архангельский М.С., Нелихов А.Е. «Эффект мезозойской бабочки, или Эволюция, которой не было» / «Природа», №5, 2017 (original article in Russian; English translation here); Силенгинский А. «Инопланетные слоны – какие они?» / «Наука и жизнь», №6, 2019 (in Russian); Schmidt G.A., Frank A. “The Silurian Hypothesis: Would it be possible to detect an industrial civilization in the geological record?” / International Journal of Astrobiology. Volume 18, Issue 2. April 2019, pp. 142-150.

II. A question on terminology

The name of a literary genre in focus may seem improper and offensive for Russian-speaking person. In Russian language the word “speculative” has the expressed negative meaning and is related more to financial activity of people, including to one that fells within the scope of the Criminal Code. Alas, it is feature of Russian language, and in this case it is no way to avoid it. In English the word “speculative” has much wider and less negative sense, meaning, among other, “contemplate, theoretical, hypothetical”. All these epithets are quite applicable to “speculative biology” concept. In Russian it is a bit difficult to pick up the equally universal term, therefore the calque from English is traditionally applied to the name of genre.
Sometimes the name “alternative evolution” is used in our country for a designation of this genre of literature, but it reflects not completely a variety of topics covered. Not all themes of speculative biology are dedicated to a certain alternative to existing phenomena and processes, and it’s not always about the evolution process.
The genre of speculative biology was initially formed mainly in English-speaking countries, and in English for its naming a little bit other term – “speculative evolution” – is used; whereas names like “speculative biology” are given as synonyms. At least, the theme is covered this way in appropriate article in English part of Wikipedia. It is difficult to agree with a designation like this, because the concept “biology” in itself is wider, and a labelling of this genre as “speculative evolution” leaves beyond the genre framework a discussion of, for example, alternative biochemistry, anatomy and physiology of invented creatures from scientific point of view. Therefore in Russian the name “speculative biology” looks more preferable.
This statement may be reversed also. Is speculative evolution possible beyond the framework of speculative biology? In our opinion, yes it is – and we can develop a theme of speculative evolution of non-biological type (alongside and together with biological one) – for example, evolution of technological systems (technoevolution) and socioevolution*.
In general, one of blind spots of modern speculative biology is that it is not conjoined with actions of intelligent actors. At best, they appear, make an affect (as a rule, nocuous one) on ecosystems and disappear somewhere – either in deep space or in nonexistence. The idea is proposed also that the sustaining of humans as an intelligent species will stop biological evolution. It is an extremely pessimistic point of view, which bothers humankind in our uneasy time. The image of the desirable future should inevitably combine biological, technological and social evolution. Here speculative biology contacts closely with science fiction, philosophy, forecasting and an immense array of practical tasks of a survival of our civilization.

* The most strict formal description of evolving system of any kind may be found in article by Hodgson G.M., Knudsen T. “Why we need generalized Darwinism, and why generalized Darwinism is not enough” // Journal of Economic Behavior and Organization, Vol. 61, 2006. pages 1-19.

III. Speculative biology as a genre and a method. A problem of the format

It is widely known that sci-fi shows the fictitious worlds. In works of the present genre fictitious organisms, ecosystems and the whole biospheres are not at the lower position. In this case it is appropriate to ask: what makes a specificity of speculative biology as a genre?
In our opinion, in these works the biology of the invented world is in focus of author’s attention, and its depiction is the basic author’s purpose.
However interests of author and reader/viewer do not always go together. For the declared purpose quasi-scientific work or encyclopedia of fictitious world represents the most natural form. Such projects really exist (for example, famous “The Snouters: Form and Life of the Rhinogrades” monograph or “Speculative Dinosaur Project” – a story about modern-time dinosaurs). However, outside the inner circle of genre fans (being also authors in their majority) and partly of professional scientists, such works are read by few people only.
Stories with heroes and a plot are interesting to people. And in attempts to break out from spec-biological ghetto authors try various ways of dressing their ideas in a story format.
The most obvious way represents the conventional fantastic novel about the scientists has faced the unknown phenomenon – this role is played by fictitious organism or biosphere. Then all we need is writing a story and creating of convincing heroes, which would absorb the reader’s attention and thus help to represent the essence of the speculative biological ideas gained through suffering. However, very few people are capable to do it. For example, late Michael Crichton managed to do it. Rather recent “Fragment” novel of Warren Fahy (the author which obviously tried to be a Crichton’s successor) contains very original idea – high-grade ecosystem made of organisms diverged from other inhabitants of the Earth soon after “Cambrian explosion” – but characters through which stories this narration is presented still look like two-dimensional supernumeraries, which only purpose is to serve as a tasty and nutritious dinner for superaggressive inhabitants of Henders island. They do not provoke any pity for them, and you don’t care about several as if main characters (which certainly succeed to do whatever they try).

Illustration to Warren Fahy “Fragment” novel. They all will die, no one is sorry for them all.

Another method consecrated by history represents just stories about animals. Here inhabitants of other worlds act as heroes. The history about them inevitably cannot avoid of some part of anthropomorphism – but this effect can be reduced up to a necessary minimum, and ways to make it are known. The genre of the story about animals was repeatedly used in stories about organisms from the geological past of the Earth (for example, in well-known Joseph Augusta’s book “The Vanished World”*), that’s why it is quite natural to use it relatively to creatures completely died out. Project “Tour to Neocene” by Pavel Volkov (one author of the present article) is made just in this way.

* English-speaking readers may also remember Robert Bakker’s “Raptor Red” – P. V.

More sophisticated approach is used by Stephen Baxter in his “Evolution” novel. This book seemingly represents a series of not narratively connected stories about ancestors and far descendants of human. Nevertheless, in finer details here and there author emphasizes that heroes of his narration are linked by bonds of family, and it gives a new prospect to his narration. And from behind a chain of turning points of the evolution getting in focus of writer’s attention the global historical plot basing upon a certain (rather dismal) philosophy is seen. In this novel (and also in the small story “The Children of Time”) Baxter managed to solve an uneasy task of showing of slow, but inevitable footsteps of evolution. In this respect, his writings cause in memory novels of his compatriot Olaf Stapledon – influential, but less popular author, the writer for writers, whose visions have affected many subgenres of fiction including speculative biology.
However, one more approach seems to be the most interesting for us. It is rather rare, but writings where it is applied successfully frequently turn to be masterpieces. Author can set himself a chain of tasks connected hierarchically. The speculative biological idea, interesting and examined in details in itself, acts thus as means for transfer of others concept, frequently of philosophical nature. Stanislav Lem in his “Invincible” has represented interaction of humans with non-sapient, but dangerous natural force, and has developed in addition very interesting idea of necrobiosphere. Peter Watts in “Blindsight” has undertaken to solve a problem of consciousness, and has invented as graphic means a community of intelligent, but not aware aliens*. Of course, these writings do not relate any more to speculative biology genre – here it is reduced again just to a method. But these are masterpieces, and the role of a method for them is honorable.

* I do not even mention Watts’ vampires – missed, but the revived species of genus Homo. In the novel, they play mainly a role of an ornament, but it is a high-grade speculative biological idea. Watts makes marvelous even “pretty-pretties”.

Anatoly Fomenko’s surrealistic pictures were used in Vladimir Tarasov’s cartoon film “The Passover” (1988)
based upon Kir Bulychev’s stories, where they created an atmosphere of the alien and dangerous biological
world of other planet.

However, speculative biology is not only a literature. Numerous authors start from the image instead of the text. It is no wonder that numerous web-projects of the present genre are resided at DeviantArt site – a platform for artists and photographers. And though founders frequently accompany their works with vast comments, picture acts as a key element. If it has drawn attention of an audience, it is possible to state a substantiation for it in any form. In that case, any storyline is frequently absent.


Images of alien creatures may represent geometrical constructions in their basis (left: artwork by Richard Wheeler) or a product of artistic imagination (right: “Foraging at low tide” by Richard Bizley).

However, an artistic image is not only a way to heart of the reader, but also a mode of work. Creating fictitious creatures, author may not start from intellectual mental constructions, but base on his own imagination, placing subsequently natural-science footing to it. The initial image may be received also from geometrical studies, and even be offered by a computer (for example, by means of Ganbreeder – the software application creating casual but plausible photo collages). This way author avoids thinking inertia and can create something essentially new.

The invented animal drawn based on a collage created via Ganbreeder software application (left top). Artist: Jakub Bobrowicz.

At last, we must keep in mind also the third incarnation of speculative biology, the cinematography. For now, creation of films abounding with computer animation is an occupation of numerous collectives; therefore, in genre in focus these films are still not numerous. Authors of this review can recall only two films strictly related to it – “The Future is Wild” and “Alien Planet” – and also a number of Hollywood blockbusters where speculative biology component is rather significant (“Avatar”, “King Kong”, “Star Wars” series). So, technologies do not stand still, therefore it cannot be excluded that in the future we shall see much more works of such kind, and even essentially new forms of expression of speculative biological ideas.
However, providing numerous examples, we necessarily take for the review of development of this genre. It is just a proper time to represent it more consistently.

IV. History of the genre

At the moment of typing of these lines, in early XXI century, speculative biology genre had taken its shape in full degree. But it’s establishment had taken place during almost the whole XX century – at first separate ideas were suggested, artworks were created, methods of reasoning and hypothesizing were made out, and they have received the further development already at the stage of “high-grade” establishment of genre, and only after a while works have appeared, which may be regarded as its samples to the full extent.
Tightness of an occupied niche leaves traces on products of the present genre. Authors of review know spec-evo projects in English, Russian, German, French and Japanese languages. Some of them – like works of Gerolf Steiner, Wayne Barlowe or Dougal Dixon – are known worldwide, and others are unfamiliar to the majority of readers. Choice of works for the present historical review will have a tendency to randomness, however we have tried to include the most known and innovative works to it.
First of all, it is necessary to make one essential reservation. Literary works in which fantastic live creatures are mentioned had been published also before the appearing of the first books which may be attributed to the present field of literary work – as a matter of fact, the most ancient from among them were myths and fairy tales transmitted from mouth to mouth. However works which can be referred to speculative biology genre differ from them in that the basic component of their plots is biology in its fantastic and invented embodiments. In such works adventures of characters represent no more than a subservient, secondary element of a narration. Formation of this literary genre had taken place gradually – from the first assumptions about the phenomena and events unknown to people using the basis of scientific evidence up to the accomplished literary works dedicated entirely and completely to invented objects and phenomena, but with scientific substantiations. Accordingly, these products could not appear earlier than the scientific approach in biology had been formed.
The process of formation of speculative biology as a literary genre may be presented most evidently as the original timeline directed from the past to the present day.

From antiquity up to modern period – this long span of recorded history of mankind may be hardly regarded as a time of occurrence of the first fragmented elements of speculative biology in literature. In this epoch scientific knowledge could hardly be separated from numerous myths, legends and tales determined human mindset. In antique times in Europe the books dedicated to the description of animals – so-called bestiaries – were published. During centuries they had been re-written, supplemented and reinterpreted repeatedly, and data from their first editions acquired with new, frequently fantastic details. In bestiaries for the first time data on live creatures which lived only in imagination of people trusting in their existence appeared. Fragments of stories of not numerous travelers, echoes of ancient myths and attendance from daily life incorporated in freakish combinations and gave birth to fantastic creatures – dragons, unicorns, basilisks and other more or less known creatures. They are related to creatures representing a subject of interest of speculative biology in fact that in bestiaries their biology is described as detailed (and also fantastic in the same degree) as at other, real animals living on the Earth today. The basic difference is that people thought these creatures real, and up to a certain stage of development of science they did not doubt of their existence. Therefore “unnatural” heroes of ancient bestiaries relate to the field of speculative biology only from a point of view of modern biological knowledge, which has left them to live only in fairy tales for ever. Nevertheless, some directions of modern speculative biology consider plausible variants of biology of obviously fantastic creatures – of mermaids, for example.

1859 – Charles Darwin publishes his fundamental work “On the Origin of Species by Means of Natural Selection”. Of course, this work cannot be regarded as a basic for speculative biology itself, but it will be expedient to mention it here, because it is an original “reference point”, a new stage in development of biology as a science. In this work the plausible mechanism providing historical development and change of wildlife, accepted by scientific community, was proposed. The significant part of projects from the field of speculative biology is dedicated to process of evolution of live organisms proceeding according to any fantastic scripts. Therefore Darwin’s work can be accepted as an important stage of scientific component of a literary genre of speculative biology, because every speculative biological project includes an evolutionary component which is tracing back to Darwin’s fundamental work.

1895 – Herbert G. Wells publishes “The Time Machine” novella (at first as a short story titled “The Chronic Argonauts”). This novel is remarkable in that in it author shows one possible script of human evolution during the invented time travel into the far future. Social stratification of human society in the future appears so deep, that it results in split of human population into two separated biological species – gracile sybaritic Eloi and lemur-like Morlocks adapted to underground way of life. In this novel some changes in nature of the Earth of the future also are mentioned. One more fragment was removed from early edition of the novel by censors. It described how during the next bound in time the story-teller appears in more remote future, where he met small rabbit-like creatures appeared to be human descendants – they were objects of prey for local giant centipedes. The picture of even deeper future shows the Earth with dying away life where invertebrates are dominant life forms.
This is a work of fiction, but it is possible to designate it to a genre of speculative biology, because its basic theme is evolution – historical development of the organic world and human being as its part.

1908 – in “Cosmopolitan” magazine article “The Things that Live on Mars” by Herbert G. Wells is published. This work is interesting in its approach to consideration of the problem. The author begins reasoning from data about natural conditions of Mars actual for that moment – gravitational pull, density of an atmosphere, availability of water etc. – and examines possible features of appearance of inhabitants of Mars by analogy to terrestrial inhabitants existing in similar conditions. Certainly, more precise information about environmental conditions of the planet is got today and doubtless traces of life on Mars are still not found. However, Wells’ approach to consideration of the problem may be considered as correct from the point of view of speculative biology. It is interesting, in the present article intelligent Martians are present as flying anthropomorphic creatures, as opposed to his earlier “The War of the Worlds” novel, where they looked similar to octopuses having thin tentacles.
The same year in Russia sketch “Live creatures in space” (also known as “The Animal of the Space”) by Konstantin Eduardovich Tsiolkovsky is published. Discoursing about opportunities of live organisms to life in extreme conditions, the author specifies the imperfections of features of anatomy of humans and animals of terrestrial type, and suggests possible ways of their overcoming. In the article hypotheses about possible alternatives in anatomy and physiology, and also about expected features of appearance which may be observed in live creatures from other planets are proposed.

1921 – in his essay “Biology of dwarves and giants”, K. E. Tsiolkovsky analyzes expected features of biology of hypothetical dwarves, giants and liliputians in comparison with human of a normal constitution. It is a part of not completed work “The Mechanics in Biology”; author began development of the present theme since 1882.

1930 – British writer and futurologist Olaf Stapledon publishes his book “Last and First Men: A Story of the Near and Far Future”. This work is dedicated to vision of development of humankind – from the nearest centuries up to the most distant future when even the Sun will begin to elden. According the book plot, in course of time the humankind will settle to other planets of Solar system and will evolve to new species – both intelligent and lacking intelligence beast-like forms. In some cases even not representatives of human line, but descendants of modern monkeys appear carriers of intelligence. Certainly, from the point of view of modern science many-armed and many-eyed human descendants look as a naive fantasy, but a level of scientific knowledge actual at the moment of writing of this book allowed assuming of such a turn of events.

1933 – in “The Journal of The American Museum of Naturla History” #6/1933 Harry Lionel Shapiro’s article “Man – 500 000 Years from Now” is published. Using an example of our own species, author shows the approach used in genre of speculative biology: he analyzes the anthropological data describing the basic tendencies in evolution of human shape available at the moment of writing of the article, and extrapolates them to a distant future, drawing conclusions about possible shape of descendants of modern humans.

1939 – in two issues of the USA-based “Astounding Science Fiction” magazine, a large article entitled “Design for Life” written by the sci-fi author Lyon Sprague de Camp was published. Analyzing the sci-fi works known at that time, the author discusses the appearance of alien organisms rendered there and the typical mistakes of the sci-fi writers. The main idea that the author conveys to the reader in this article is to rely on the real capabilities of living organisms. Using examples from the nature of the Earth, the author shows that, due to the objective laws of physics, the sizes and shapes of living organisms come down to very few variants, which does not deny the profound differences in other characteristics. He also talks about the possible variants of the biochemistry of alien organisms and the restrictions they impose on living beings. The main idea of the article is that the appearance of a living organism is shaped by objective environmental factors that should be taken into account when designing the appearance of fictional species.

1948 – in the USSR, a brochure by astronomer, corresponding member of the USSR Academy of Sciences G. A. Tikhov “The latest research on the issue of the vegetation on the planet Mars” was published. It outlines author’s conclusions about the existence of vegetation on Mars and its seasonal changes, based on changes in the appearance of the planet’s disk during observations (the first observations and conclusions about the existence of vegetation on Mars were made by the author in 1909). Tikhov’s observations laid the foundation for the emergence of a new science – astrobotany – which studies the vegetation of other celestial bodies. On March 15, 1947, The Astrobotany Sector of the Academy of Sciences of the Kazakh SSR was established, headed by G. A. Tikhov until his death in 1960.

1951 - Soviet biologist Alexander Alexandrovich Lyubishchev writes a series of notes having a general title “On Imagined Zoology and Biology in general”, where he reflects on the possible appearance of inhabitants of other planets, and also specifies the factors determining shape of these creatures.

1953 – G. A. Tikhov's “Astrobiology” book was published in the USSR, developing the author’s earlier conclusions about the existence and seasonal changes of vegetation on Mars. In support of this idea, the author presents the results of studies of the optical properties of the Earth plants living in extreme conditions, comparing them with the properties of supposed Martian plants obtained from observations of the disk of Mars via the telescope. According to G. A. Tikhov, the Martian vegetation should be of cyan, blue and purple coloration, and the supposed vegetation of Venus should be yellow, orange, or red. The author also explores the limits of endurance of various groups of Earth-based living organisms and suggests the possibility of the existence of their analogues in the natural conditions of Mars.

1957 – book of Soviet anatomist and paleontologist Alexey Petrovich Bystrov “Past, Present and Future of the Human” is published. One parts of this issue is dedicated to problems of the future evolution of human body. Analyzing frequency of occurrence of one or another feature of human body and citing opinions of outstanding anthropologists of his time, author tells about the range of variability of features of human body anatomy, and about hypotheses related to directions of human evolution in the future. However he does not agree with contemporary anthropologists that human is an object of selection, and believes that evolution of human body is already completed.

1961 – book “The Snouters: Form and Life of Rhinogradentia” by Gerolf Steiner (under the pseudonym Harald Stümpke) was published. It is the first high-grade sample of the book of speculative biology genre telling about features of biology and evolution of fictitious group of live creatures – snouters, or rhinogrades. Book is created as a review of biological features and ecology of various representatives of this group, and is written so realistic that its first readers have mistaken it as a description of real group of modern animals. Now this theme keeps popularity among fans of a genre, book had numerous publications in various languages, and enthusiasts create realistic models of creatures invented by Steiner.
It is of interest to note, that in contrast to the majority of other writings treated here, Steiner/Stümpke’s book was recognized also among professional biologists. One author of the present article had the pleasure to managed to be in Zoological Museum in Moscow at the conference addressed to 50th anniversary of the book (which had been successfully organized in April, 1). Lecturers informed about new species and groups of rhinogrades discovered in various parts of the world, and the major paleontologist and science popularizer Andrey Zhuravlev has finished conference, having assumed in his statement that similarity of rhinogrades and mammals is purely convergent, and this group actually descends from Cambrian worm-looking Cephalorhyncha.

1962 – K. A. Lyubarsky’s book “Essays on Astrobiology” was published in the USSR. A proponent of the idea of the habitability of Mars, Lyubarsky criticizes the views of the G. A. Tikhov’s scientific school on the appearance of Martian vegetation and defends a different vision of the appearance of hypothetical Martian plants, which he cautiously names as “Martian autotrophic organisms”. He analyzes data on the nature of Mars, points out the mistakes of both opponents and supporters of the idea of habitability of Mars, and provides data that he considers evidence of the presence of life on Mars. Later, the successful flight of the “Viking” automatic interplanetary stations to Mars (1976) forced Earth scientists to reconsider information about the natural conditions of Mars and abandon previous ideas about the habitability of Mars. In fact, this conclusion transferred all hypothetical Martian living organisms, which existence was considered from a scientific point of view, into the category of fictional creatures, and the works of Tikhov, Lyubarsky and other researchers, originally created as scientific ones, passed into the category of speculative biology works, since they began to fit one of the key criteria of speculative biology – a scientific approach to the biology of non-existent organisms.

1963 – “The Magazine of Fantasy and Science Fiction” published another article by Lyon Sprague de Camp, “How To Plan A Fauna”. The article outlines an ecological approach to speculative biology: a fictional live being species is considered as a component of the ecosystem that gave rise to it. The appearance of this ecosystem of a hypothetical planet is influenced by objective cognitively penetrable factors, and the task of the project designer is to take these factors into account, reworking them in relation to the conditions of the invented world.

1974 – “Smithsonian” magazine published an article “Exotic Bestiary for vicarious space voyagers” by paleontologist Bonnie Dalzell, telling about alien organisms. The author analyzes the natural conditions of several hypothetical planets with different climates and different gravity; then, based on information about the natural conditions of the planets, she determines the directions of evolution of hypothetical extraterrestrial animals, and abiotic factors affecting the direction of evolution of the organic world of these planets. As a result of this work, the article provides brief descriptions of the main features of the appearance and images of typical representatives of the fauna of each of the planets.

1976 – Leo Lionni’s book “Parallel Botany” is published; it is dedicated to the description of biology and role in human culture of “parallel plants”, which existence and some features of anatomy and living abilities break laws of nature. It can be mentioned here exclusively because plants become a subject of interest of authors of books and projects of speculative biology field very rarely.
In the same year, “Galaxy Science Fiction” magazine published a short article “Hexapedia” by paleontologist Bonnie Dalzell, which represents a kind of study of six-legged vertebrates in folklore turning into an analysis of environmental factors that could contribute to the emergence of three pairs of limbs in vertebrates.
Also the book “Other Senses, Other Worlds” by Doris Jonas and David Jonas is published this year, offering the reader to look at the problem of fictional intelligent beings from an unexpected side, from the standpoint of the prevailing sense that is different from the vision of human type. The authors analyze the natural conditions in which living organisms could benefit from the use of other senses, and then they depict the possible appearance of a civilization of these species, taking into account the influence that the peculiarities of perception of these creatures have on it.

1979 – this year, an event happened unnoticed, which became known to the general public only at the beginning of the 21st century: the writing of Robert Freitas-Jr.’s comprehensive “Xenology” book was completed. This book had never been published in print, but became publicly available in HTML format only in 2008, when it was fully digitized and posted on the author’s website. The book examines the problem of alien living organisms and civilizations from various points of view; it includes large sections focusing on the biology of alien organisms.

1981 – this year a significant event opening a new stage of development of speculative biology genre had taken place: Dougal Dixon’s book “After Man: A Zoology of the Future” had been published. This book is first of three widely known books by Dixon which has determined the basic thematic directions of speculative biology. The book tells about evolution of biosphere 50 million years in the future. Live organisms described there are grouped according natural areas, and represent mostly vertebrates. In the book the variant of evolution of the organic world under condition of disappearance of human civilization and people is considered. The present book has sharply increased the interest to speculative biology genre and even had managed to break through “Iron Curtain” – in 1983 a favorable review in “Priroda” magazine with two illustrations* was published. In 2017 it was published in Russia in its entirety. Many ideas stated in this work became rather popular among the fans of speculative biology.

* Крылов И.Н. «Знакомьтесь: животный мир будущего (вместо рецензии)» / «Природа», 1983, №6, с. 126-128 (in Russian).

1982 – brochure by Dale A. Russell and Ron Seguin “Reconstructions of the Small Cretaceous Theropod Stenonychosaurus inequalis and a Hypothetical Dinosauroid” is published; here the hypothesis about an opportunity of evolution of small predatory dinosaurs to intelligent forms is proposed for the first time, and also the description of hypothetical intelligent dinosauroid and features of its anatomy is given. In “Omni” magazine #5/1982 article by Jeff Hecht and Gurney Williams III “Smart dinosaurs” popularly representing the hypothesis of Russell and Seguin about intelligent dinosauroid, illustrated with reconstruction of Stenonychosaurus (now classified as Troodon) and a portrait of hypothetical intelligent dinosauroid, is published.
The same year in “Omni” magazine #11/1982 article by Pamela Weintraub “Visions of Man Evolved” is published. Here Dougal Dixon shares his vision of evolution of organic world in the future, but now in different initial conditions, in case of surviving and the further evolution of humans, and of accompanying transformation of a nature. Many ideas by В. Dixon stated there seem fantastic today, especially in view of that earlier works with more cautious and feasible forecasts had been already done, like G. L. Shapiro’s article mentioned above.

1983 – “Systematic Zoology” magazine published an article about caminalcules, a fictional group of living organisms that were invented in the early 1960s (or even earlier) by American entomologist Joseph Harvey Camin (1922-1979) for taxonomy classes with students. The fictional nature of this group of living organisms makes it possible to exclude a certain bias when studying the principles of classification and various evolutionary phenomena (parallelism, convergence, the duration of the existence of species, etc.) using their example. Their biology remains a mystery, but their morphology, paleontology and phylogenetic tree are fully known, and it allows them to be used as educational objects.

1988 – the second Dougal Dixon’s book – “The New Dinosaurs: An Alternative Evolution” has come out of press. In the present work author describes possible species of dinosaurs which could inhabit the Earth today on condition that Cretaceous-Paleogene extinction event never happened. Ideas of this book appeared very influential among fans of speculative biology: this theme was continued by well-known in early 2000th web-project “Speculative Dinosaur Project”, or simply “Spec”; it is kept in our days as separate pages in foreign sites*.

* Translation of this project into Russian goes on now. It can be seen in this site. Saved English pages are also placed there.

1990 – this year has pleased fans of speculative biology with two cult works at once. First of them is an illustrated book of writer and artist Wayne Barlowe “Expedition” – the story about travel of the earthman as a part of joint expedition of people and aliens to the planet Darwin IV, and about studying of its rich flora and fauna. The basic theme of the present book is the description of pristine fauna and flora of this planet, and biological features of extraterrestrial live organisms. In 2005 the film “Alien Planet”, where some of the species described in the book are shown, albeit with some changes from the author’s description, was created on the basis of this book.
The second famous speculative biology-related book published this year is third Dougal Dixon’s book “Man After Man: An Anthropology of the Future” dedicated to possible evolution of our own species in the future. Author’s ideas represented in it differ considerably from the ideas stated in article from “Omni” magazine and are based in greater degree upon real features of modern humans. However, in this book there are some fantastic assumptions bordering on mysticism, not finding any confirmations in modern biology – telepathy, clairvoyance, hereditary memory. Later the author admitted that the book appeared not too successful because during the work he had to change a lot of things from initial idea. Therefore he has resigned from plans of republishing it again anytime and anywhere.
The same year fantastic novel “The Dawn on the Planet Earth” by Svyatoslav Loginov had been written. The book takes place right at the end of Mesozoic, when on the planet the civilization of intelligent dinosaurs has appeared (the author does not name them in the text though little-known at that time Deinocheirus was meant there). These creatures had developed an agriculture (as mariculture) and beginnings industry, but the global cooling caused by their activity killed both them and numerous other species. The history of life of one of last representatives of their species – a wise person unsuccessfully trying to warn his congeners about the danger threatening to them – makes a basis of book plot. The story is focused first of all on the ecological problematic, however the world shown in it is shown so spectacularly and convincingly, that the book represents one of gems of speculative biology genre.

2001 – the beginning of XXI century is marked by a new stage of development of speculative biology – by attempts of giving forecasts from scientific point of view. This year first such book was published – “Future Evolution” by Peter Ward. The author examines mechanisms and principles of events of mass extinction in the past, pattern of human influence to nature presently, and tries to predict the events that await biosphere in the nearest and a long-term future. The book is popular scientific (more precisely, speculative – i. e. containing original serious reasoning, which, however, is insufficiently strict to publish it in reviewed scientific magazine), and the artwork insets representing the world of the future, are only illustrations in it and take a small part of the volume of the book. The author is the supporter of sustaining and long evolution in the future of humans and their descendants.

2002 – book “What Does a Martian Look Like?: The Science of Extraterrestrial Life ” (republished as “Evolving the Alien: The Science of Extraterrestrial Life”) by Jack Cohen and Ian Stewart comes out of press. In this work authors have considered a theme of extraterrestrial life from various points of view – from chemical bases of the life itself up to the possible structure of a society of intelligent aliens.

2003 – one more “fruitful” year for fans of speculative biology. This year the TV series “The Future is Wild” was released, and the book with the same title, repeating and explaining the contents of film was published (in Russia also). The present project shows the appearance of the Earth 5, 100 and 200 million years in the future, and creatures inhabiting the planet. Not all ideas shown in film are possible to agree with, and sometimes spectacularity partly masks biological imperfection of the project. However as a whole the project has gathered a significant amount of admirers.
The same year Stephen Baxter’s novel “Evolution” was published. The basic subject line of the book is an evolution of primates from first small beasts of dinosaur epoch through lemurs and apes to people, and also the further evolution of human descendants in the future, down to epoch 500 million years from present time, when last descendants of people die. In addition, this book contains also elements of other direction of speculative biology, which may be conditionally named as “cryptopaleontology”: in some chapters it is told about hypothetical intelligent dinosaurs of Jurassic period, and about other creatures which have left no traces in the fossil record known to people. The chapter about intelligent dinosaurs titled “Hunters of Pangea” was written in 2002 as a separate novel, and it is included to the book with few changes.
In Norway the book by Norwegian astrophysic Eirik Newth “Liv I Universet” (“Life in the Universe”) was published, where in popular form author tells about life and its evolution, about the factors determining the body shape of live creatures, and about possible shape of inhabitants of other planets. The book is not dedicated to any separate speculative biological project, but it describes the approach to consideration of this problem characteristic for the present literature genre. In Russia this book was published in 2013.

2005 – Stephen Baxter’s short story “The Children of Time” is written, narrating about the destiny of human descendants in the far future, about change of environmental conditions, extinction of animals known to us, and about the appearing of new ones, and about changes of the Earth during hundreds millions years. Each short story illustrates a new stage of development of fauna and flora of the Earth – however a planet all the same remains to be a world of people, down to decline of life at open spaces of New Pangea. As one reader from “FantLab” site has fairly noticed, every chapter of this short novel can be developed to a high-grade literary work. The same year the mysterious Skull Island, where famous King Kong lives, had been investigated from the point of view of speculative biology, and had obtained a detailed description of its fauna: book “The World of Kong. A Natural History of Skull Island” by Daniel Falconer was published. In it creatures inhabiting this “Lost world” and ecosystems of the island realistic from the point of view of biology are described.

2008 – in abyss of Internet book by Mehmet Cosemen (aka Nemo Ramjet) entitled “Alltomorrows” had appeared. This perfectly illustrated work never published on paper tells about destinies of numerous descendants of humankind settled across the Galaxy, about their falling up to beast condition, and about new discovering of intelligence. The book is not without fantastic (relatively to biology) element of its plot: fanatical masters of genetic manipulations of space Qu race act as “deus ex machina”, having intervene in natural evolution of humans by means of directed artificial manipulations, and having started it up in the weirdest directions. However subsequently these creatures appear left for the mercy of fate, and their further evolution is influenced exclusively by natural selection.

2009 – Warren Fahey has written the fantastic novel “Fragment”, which basis is an idea that soon after “Cambrian Explosion” on the Earth an alternative group of land-dwelling organisms has evolved. They have developed life on land at the remoted continent, but by virtue of features of their metabolism had lost an ability to contact to sea water, which is a poison for them now. For many millions years among them analogues of insects, mammals and other animals, and also intelligent forms had evolved. However in due course of time, by virtue of geological processes, their house decreased in size, and up to now only tiny Henders islet in the heart of Pacific Ocean has remained from it. At this island the expedition appears and founds that its inhabitants in due course of evolution became terribly aggressive and represent danger to the rest of the biosphere. The biological idea of the novel is rather interesting, though it is vulnerable for criticism, and from the literary point of view, unfortunately, it is rather weak.

2010 – in Japan two-volume Dougal Dixon’s book “Greenworld” is published. It describes the extraterrestrial life and interaction of Earth human colonists with nature of the planet over series of generations. Unfortunately, at the moment of writing of these lines it is the only edition, and the language barrier and absence of the information do not give an opportunity to tell anything certain about the contents of this book.

2012 – it is a year of the appearing of the book “All Yesterdays” created by collaborate work of zoologist Darren Naish, paleontologist John Conway and artist Mehmet Kozemen. Named by analogy to M. Kozemen’s book “Alltomorrows”, this book narrates about questions, which frequently remain “overboard” of paleontology sciences and become only an object of assumptions and imaginations – that is, become an object of research for speculative biology. How much did dinosaurs grow fat? Could plesiosaurus have a motley bright coloring? How did Tyrannosaurus sleep? Beautiful illustrations of this book represent an attempt to answer questions like these to present the extinct animals in their daily life, where predators not only hunt, and herbivores not only eat or run away from them. And in order to show how little we know about fossil animals more evidently, authors have tried to reconstruct modern animals, having taken from modern knowledge of them only that dribs and drabs, which paleontologists have, and having figured out all rest on its basis.
This theme has caused genuine interest in readers, and authors have declared competition of artworks based on “All Yesterdays”. The part of great amount of works created by artists has composed one more book – “All Your Yesterdays” made in 2013 as an electronic edition. At least one idea proposed in this book has found its embodiment in real world: it has actually predicted features of the fossil animal found approximately at the same time.

2013 – 1st volume of “Cryptozoologicon” book created by Darren Naish, John Conway and Mehmet Cosemen is issued. The part of the description of cryptids is dedicated to their research from the point of view of speculative biology. The second volume, as of the present moment, is not written yet.

2015 – one of the newest speculative biology-related books at the moment of a spelling of this review has published: “Tomorrow. Animals of the future” (French: “Demain, les animaux du futur”) by Mark Boulay and Sebastien Steyer. Birds instead of ground mammals, cephalopods replacing dolphins, and the bats living their whole life in flight – these are some of the creatures described in the book. The book tells about the life 10 million years after our epoch, when the fauna is restored after human-induced global warming. Work is plentifully illustrated, but as of the present moment it was published in French language.

2022 – A. N. Kvashenko’s “Theoretical Draconistics. Could evolution have created a dragon?” book was published in Russia. This item describes the possibility of the emergence of a traditional European dragon – flying, fire-breathing, and also three-headed in its Russian version – from the point of view of biology.

This review does not include numerous web projects and separate selections of speculative biology-related artworks, because their amount is very large, and sometimes they may be inaccessible, being saved only as the separate pages by enthusiasts of speculative biology genre. We can hope only to the increasing of the number of supporters of speculative biology, and to the continuation of the history of genre.

V. Subject matter

Books and network projects, and the separate illustrations created in speculative biology genre, now exist in great numbers, therefore it is already quite possible to make some generalizations and to analyze tendencies existing in it. Creations of genre form a number of thematic directions, which we here shall try to highlight and to describe.
However before to undertake the description of concrete directions, we shall state criteria of classification. It will not only give logic severity to a statement, but also will enable us to allocate themes, ignored by authors meanwhile.
In the present article we propose to classify products of speculative biology as follows:

1. According the restrictions imposed on author:

2. According the time span in focus:

3. According the subject of consideration:

Of course, it is not the only possible classification. Domenic Pennetta, the creator of the electronic “Astrovitae” magazine, submits the following classification of works of the speculative biology genre:

Alternative evolution

It is one of the most popular themes of speculative biology-related projects. The first large work in the present direction became Dougal Dixon’s book “The New Dinosaurs: An Alternative Evolution”, where the possible forms of dinosaurs existing on the Earth today are shown, but with one essential condition: they have continued to exist and to evolve without Cretaceous-Paleogene extinction. From the discussion of this book, well-known online project “Spec” (“Speculative Dinosaur Project”) has grown. In general terms, the timeline bifurcation of the Cretaceous-Paleogene border is very popular even among sci-fi writers which are not concentrated exclusively on speculative biology genre. It is enough to recall “Eden” trilogy by Harry Harrison as an example. Other “forks” in time are less popular, however there are some ideas dedicated to alternative Mesozoic (without Permian-Triassic extinction event). Also possible variant of alternative evolution may become the assumption of extinction of any large group of live organisms at the beginning of its existence – usually dinosaurs are chosen for this role.
An alternative way of evolution of any separately taken group of live organisms may be regarded as a subdivision of the previous theme. This direction pays the main attention to a separate group of live organisms, not купфквштп features of evolution of others taxa and biosphere in general. Examples of such kind of hypotheses are flightless pterosaurs and chiropterans, and also intelligent dinosauroids. In 70th-80th of XX century a popular character of speculative biology was hypothetical intelligent dinosauroid proposed by paleontologist Dale A. Russell as an intelligent descendant of Troodon dinosaur. However this idea had been further criticized from the part of zoologist Darren Naish, among other, for unjustified “anthropomorphism”. In view of the newest data on dinosaurs the image of hypothetical intelligent dinosauroid has changed now in great degree – it began to resemble a bird with teeth and forepaws similar to underdeveloped wings. It looks so in works of artist Simon Roy. Sometimes even human becomes an object of consideration of authors. Among examples of recent years a remarkable example is “Graham” – hypothetical “crush-resistant human” invented in 2016 by Australian scientists.
Unfortunately, an alternative history of ecosystems is considered much less often – probably, by virtue of insufficient development of this theme in science. Although in some cases the situation simply demands to establish in this occasion. For example, surviving of non-avian dinosaurs in Cenozoic places a question: could steppe landscapes known to us now appear in that case? Authors of Spec project answer it affirmatively, connecting thus the appearing of steppes mainly with aridization of climate. Modeling of alternative scenarios where live organisms act as the major driver of ecosystem reorganizations is much more difficult, but represents a great interest. We hope to see more of such projects in the future.

Cryptozoology

Alternative evolution of a separate group of organisms may be brought closer to realities after asking a question: what if certain organisms unknown to us live along with us on the Earth today. Here we enter the field of cryptozoology – a special direction of “parabiology” which represents a special area of knowledge for a long time and has its own army of adherents ready to search for mysterious and imperceptible “cryptid” animals like yeti and modern African dinosaurs. Within the framework of speculative biology the existence of live organisms considered by cryptozoologists is accepted by default, and a subject of debate is their possible real prototype from among unknown to people representatives of known groups of animals, and also their relations and systematics. Example of this approach in speculative biology is a book “Cryptozoologicon” by Darren Naish, Mehmet Cosemen and John Conway, discussing, in addition to other matters, a question on real systematic position of cryptids.
In the field of cryptozoology the border between science and creative work is blurred up to indistinguishability. Perhaps, the main difference is the relation of the author to things he writes. Serious cryptozoology-related books aren’t too different from writings from the field of speculative biology in their content: there more or less proved attempts to link stories of eyewitnesses with scientific knowledge of the extinct inhabitants of the Earth are also done. We see such approach in the book “On the Track of Unknown Animals” by Bernard Heuvelmans. And in work of Russian author Alexander Kondratov “Chance for a Dinosaur” (expanded and revised version of the book “Search for a Dinosaur in Depths”) we see a formal consideration of criteria which a population of ancient aquatic reptiles should correspond to survive up to modern epoch. This chapter (which we urge you to read) rather closely resembles “The Demiurge’s Cookbook”, which is an appendix to the present article.

Cryptopaleontology

The author of these lines does not apply for originality, denominating the present direction of speculative biology by analogy with previous one. Subjects of consideration of the present direction are those creatures, that are hidden in gaps of the known fossil record, which incompleteness had been noted in due time by Ch. Darwin and Ch. Lyell. They lived on the Earth, but have not left descendants and traces in the geological record. The reasons of this situation are diverse. They could inhabit places where the fossilization of their remains is impossible – tropical forests, for example. Alternatively, these were creatures which by virtue of the ephemery can not be buried in sediments a priori – for example, jellyfishes or mushrooms. Or they have vanished off the face of the Earth too quickly. Stephen Baxter has written the novel “Hunters of Pangea” included later to the book “Evolution” right about such animals. And in “Evolution” itself Baxter mentions creatures which had not manage to leave their traces in paleontological record – monstrous “air whale” pterosaur and Cenozoic dinosaurs of Antarctica, whose traces of existence had been erased by glaciers locked the continent.
In addition, the respective area of cryptopaleontology includes assumptions of unknown features of shape and way of life of known kinds of live creatures of the past that cannot be known from their fossils. Book “All Yesterdays” by D. Naish, J. Conway and M. Cosemen is dedicated right to this question and evidently shows, how many questions exists, which paleontology is not able to answer and which can become a subject of assumptions and imaginations. Mark P. Witton in his article “Patterns in Palaeontology: Palaeoart – fossil fantasies or recreating lost reality?” addresses the same question.
It is also possible to regard as examples of the present direction of speculative biology the hypothetical ancestors of one or another group of live organisms. One of the most known ones among them is Pithecanthropus in the meaning given to this concept by Ernst Haeckel.

Evolution and biology of invented group of creatures on the Earth

Having come off from a sordid reality, we can invent a completely new group of organisms, which lived or live until now on the Earth. Thus the history, planetary, geological and geographical context remain former, but in anatomy, physiology and evolution of the group in focus only few things limit author. The first step of speculative biology as such was made in this direction, when book by Gerolf Steiner (aka Harald Stümpke) “The Snouters: Form and Life of Rhinogradentia” saw the publication. The zoological joke had an enormous success: readers have believed in reality of these creatures and their tragic fate due to detailed descriptions of biology, behavior and anatomy, and also to discussion of phylogenetic relations of these amusing invented animals. In Internet there are some projects dedicated to biology and evolution of dragons and other fantastic creatures – as if they were a real group of live creatures descended from the common ancestors with other groups of Earth animals. This theme has developed even in cinematograph. The film “The Last Dragon: A Fantasy Made Real” created in 2004 includes the analysis of an opportunity of existence of real dragons in our world from the point of view of biology. In addition, in 2013 mock documentary film “Mermaids: The Body Found” was realized, being made as journalistic investigation of the facts of existence of real mermaids in modern world. The modern mythology has procreated its own monsters, and they also became a subject of interest of speculative biology. Special attention among them giant creatures from modern cinema had got – ones like well-known Godzilla and other monsters known as “kaiju” (name of Japanese origin).

A whole brood of fictitious creatures – from animals from myths of folks of the world up to city legends – is represented in Tim Morris’ project IAOR – “International Aerial Organisms Register”. Author develops non-trivial idea that once in Cambrian some groups of sea inhabitants have developed air habitats, bypassing land ones. Firstly they soared near the surface of water, but the occurrence of flying vertebrates had compelled them to rise higher and higher, and eventually has pushed them out to stratosphere. And they live there until now, only occasionally being seen by people and causing rumors about dragons, angels or UFOs. Certainly, competent authorities know about them, but in order to prevent a panic they conceal this information from the public, stating it only in top secret documents, and the present project is made to imitate one of them.
It is amusing, that a creativity of some creationist authors asserting the biblical version of the formation of our world appears rather close to speculative biology. In USA and Europe books of young Earth creationists are published, where the point of view is stated, according to which ancient dinosaurs lived simultaneously with people and were known to them as dragons. The most passionate authors assert that expanded nasal bones of duck-billed dinosaurs contained fire-producing apparatus and try (unsuccessfully for now) to reconstruct the biological mechanism of fire breathing, mentioning the bombardier beetle as a possible prototype. However the plausible mechanism of biological fire producing is still not proposed by them yet and the proposed versions do not withstand any criticism of the specialists.

Evolution of Earth life in the future

Many books and projects are also dedicated to the present topic. The main issue on that authors concentrate their attention is human influence to the nature. The significant part of projects describes evolution of the Earth inhabitants in the future provided human extinction. The most known book on this theme is “After Man: A Zoology of the Future” by Dougal Dixon (1981). He predicts the end of our civilization because of exhaustion of resources necessary for its development, and portrays the evolution of new forms of animals on the unpeopled Earth. This theme is continued by the project “The Future is Wild”, which founders simply “send” mankind into the space at the minimal explanation of the reasons for this. In such projects Earth megafauna of the future descends from medium-sized species of animals survived in human epoch: rabbits, small antelopes and even turtles. Consequences of human activity like introduction of biological species to new areas where they could not settle by natural way are frequently ignored – probably, because of consideration of the organic world of the Earth only in most general terms*.
In other versions of events in the future, people sustain, and such projects pay attention to the influence their activity renders on the evolution of life. Example of such kind is a web project “Urban future”. Some ideas on this had been expressed earlier in Peter Ward’s book “Future Evolution”. The present book is remarkable in that the detailed scientific analysis of various aspects of human influence on nature and of their remote consequences is given there. The occurrence of essentially new habitats seems to be an interesting development of this group of scenarios. Ward addresses it, describing the organisms adapted to living in dumps. However, dumps represent a product of the extremely unstable expansive economy of modern type. Such condition will hardly last for a long time – and following it dumps will also disappear. The occurrence of the organisms adapted to essentially new food sources (such as plastic) or entering other ecological connections (for example, wild-living cyborgized organisms) seem to be much more plausible.

Currently one more variant of development of events, “alternative Quaternary” theme, is not worked: development of life on the Earth in the future in conditions when intelligent human has not evolved, and the line of people has stopped its development approximately at the level of archaic representatives of genus Homo.

* The successful exception is “Neocene Project” created by Pavel Volkov – one of authors of present article – where the introduction of biological species to new habitats is consistently taken into account. So, as main large herbivores in Australia and New Zealand ungulates (descendants of camels and sheep accordingly) are shown there.

Human evolution in the future

As a matter of fact, it is a particular case of the previous theme, but the basic attention is given to the evolution of our own species, usually without consideration of a history of our global neighbours. During the development of the projects in focus the role not only of biological, but also of social component of human being, and its intelligence are taken into account. This theme is more appropriate to consider as a separate one because the amount of ideas and projects related to human evolution in the future is comparable to the amount of projects dedicated to evolution of other forms of the Earth life in the future. Frequently repeating motive of such works is loss and repeated discovering of intelligence.
As the first large work on the present theme may be considered “Last and First Men: A Story of the Near and Far Future” by Olaf Stapledon, where evolution of people on the Earth and other planets of Solar system during many millions years is shown, being directed both by artificial intervention of intelligence and forces of nature. Another work influenced the formation of genre is Dougal Dixon’s book “Man After Man: An Anthropology of the Future” telling about possible ways of evolution of human descendants on the Earth. In book “Alltomorrows” by Mehmet Cosemen (Nemo Ramjet) evolution of human descendants on the broadest possible scale is shown – during hundreds millions years across the whole Galaxy. These three books are united by one common feature – human evolution at a certain stage had been influenced by purposeful intrusion of intelligent creatures – either people (Stapledon, Dixon), or aliens (Cosemen).
Somewhat different view of human evolution is shown in Stephen Baxter’s book “Evolution”: human descendants originated exclusively due to natural evolution – ground-dwelling, arboreal and even colonial ground-digging forms. After the collapse of civilization they quickly lose intelligence, and at the dawn of human race the destiny of last descendants of our branch appears under the direction of symbiotic tree.

Xenobiology

The name of this direction of speculative biology already tells a lot about its theme. The present subgenre is dedicated to alien life – to possible appearance of live organisms of another planet similar or not similar to Earth. Here author’s imagination gets the plenty of room compared to the previous cases. Author is not confined with restrictions of Earth conditions and acts actually like a creator of the new world. Nevertheless, the laws of celestial mechanics determining physical parameters of the described world* and principles of evolution still work here. Though the latter were deduced on the basis of studying of Earth life, their further studying has shown that similar patterns are actual for the most diverse systems – not only for biological, but also for social, technical and other ones**.
We can regard as a first example of work of this direction Herbert G. Wells’ article “The Things that Live on Mars” (1908), where assumptions of possible features of shape and physiology of inhabitants of Mars are made based upon data on conditions of the planet actual in author’s epoch. In 1940th-50th known Soviet evolutionist Alexander Lyubishchev considered these issues. Among modern writings of the present direction of speculative biology there are books “Expedition” by Wayne Barlowe (1990) and the film “Alien Planet” (2005) shot on the motives of it, “Snaiad” web project by M. Kosemen (Nemo Ramjet) and also little-known “Greenworld” – fourth book by Dougal Dixon.
It’s interesting, now during the work on sci-fi films some authors show the thorough approach to designing of alien world, and in order to give plausibility to their movies try to take into account principles of evolution and base upon known on the Earth analogues of designed live creatures. Such approach was used by producer James Cameron at work on his “Avatar” movie. The ecological approach to reconstruction of fauna of unknown planets was shown by creators of well-known “Star Wars” on the example of fauna of Naboo planet. More detailed view of fauna of various planets of the series is shown in book “The Wildlife of Star wars. A Field Guide” (2001) by Terryl Whitlatch and Bob Carrau, where the information about ecosystems of planets, understandably appeared beyond the frameworks of film plot, is given. Opportunities of modern cinematograph enable to embody this approach on screen maximally realistically, therefore now the problem of unnaturally looking worlds is a problem of script writers and artists working on film.
Depicting of other worlds gives an opportunity to imagine essentially new ecosystems. So, Memo Cosemen in his “Snaiad” project makes two biomes having no analogues on the Earth: sprogg (the territory covered with a continuous layer of spongy vegetation of multimeter thickness) and tower savannas (plains where from time to time hard and looking like towers complexes of symbiotic plants grown together may be seen). Rather nontrivial variants of ecosystems are depicted at the abandoned site “Worlds of Robert Ibatullin”, which in due time was moderated by the sci-fi writer more known now as an author of “The Rose and the Worm” novel. Here we can see soaring woods and completely atmospheric ecosystems of the giant planet, and purely detrital communities living on the leeward edge of the night side of the planet, which rotation is gravitationally synchronized with its star. At last, it is necessary to mention famous Amoebic Sea – a monstrous colony of protists from Wayne Barlowe’s “Expedition”.
If any Earth-related speculative biological projects are obliged to correspond somehow with the deep past of our planet, and frequently also with its present condition substantially determined by a civilization, xenobiology enables to give purely synchronic, instantaneous image of the world. Here a good example is Barlowe’s “Expedition” mentioned above. The author tells to us about results of one expedition to the planet Darwin IV, which members did not study geological sediments and (for ethical reasons) almost did not investigate internal anatomy of organisms. Virtually all information accessible to us relates only external shape and behavior of its inhabitants. The author tells nothing about evolutionary history of Darwin IV, but obviously had meant it when created local animals. A discovery of unobvious connections between them brings a special pleasure at reading of the book.

* It is interesting, that geological laws represent rather loose restriction even for scenarios of evolution in the future, because the appropriate scientific area is advanced much worse, than astronomy. Therefore the same author – Timothy Morris – managed to create two projects, in one of which the Earth 600 million years in the future is almost entirely covered by ocean (“Panthalassa Nova”, where continental drift has stopped, and the rest of land was erased by erosion), and in another one after the same term from oceans only small extremely salty reservoirs remain (“Millions after mankind”, where the appreciable part of an atmosphere was broken off by close gamma burst, water began to evaporate in space, and geological activity remained former).

** Perhaps, the best formal description of the generalized Darwinian evolution is given in this article: Hodgson G.M., Knudsen T. Why we need generalized Darwinism, and why generalized Darwinism is not enough // Journal of Economic Behavior and Organization, Vol. 61, 2006. pages 1-19.

Alternative biochemistry

The further removal of restrictions on the way of xenobiology leads us to the kingdom of alternative biochemistry. As a matter of fact, it is a revision of bases of life: consideration of candidatures of other chemical elements to the role of a basis for biopolymers. In normal conditions close to Earth ones, the best version for life is carbon, combining optimally suitable reactionary ability, an opportunity of formation of long chains of atoms and stability of compounds. The point of view asserting universal character of carbon-based life is named “carbon chauvinism”.
But in extreme conditions, when carbon-based compounds break up or simply are impossible to form, origin of life based on the biopolymers formed by atoms of other chemical elements is not out of the question. Accordingly, in this case metabolic reactions and process of getting of energy by creatures of such kind may have the most freakish external display. As life on the Earth has already “established” with the type of biochemistry some billions years ago, such reasoning is connected to discussion of an opportunity of life on other planets. In this direction of speculative biology the possible appearance of extraterrestrial live creatures turns to a certain minor detail, because the basic attention is given to biochemical component of life.

Evolution at the terraformed planet

In the present direction of speculative biology the setting is also an alien planet, however the main theme is evolution of representatives of Earth life in new conditions, at the artificially terraformed planet. People or hypothetical race of intelligent creatures from space may, and even non-sapient creatures which somehow have got an ability to cross space may act as terraformers and creators of the new world – in this case it is not important. The basic attention is given to the process of evolution of considered groups of Earth live creatures in “sterile” conditions of absence of competition to representatives of others taxa, when they can realize their evolutionary potential to the full. Books of such direction had not been published yet, but among web projects we need to mention perfectly illustrated and elaborated “Serina” project (created by Dylan Bajda) dedicated to evolution of simple Earth canaries introduced to terraformed planet.

Other evolution

The given group in classification can be regarded more as theoretical one, because such projects are almost not present. Among authors of speculative biological genre the belief dominates, that the only possible variant of evolution is the Darwinian biological evolution known from the fossil record mainly of Phanerozoic eon. Any modifications of its mechanism are regarded as impossible, or (in case of human economic activities) immoral. Therefore in speculative biology the most obvious example of out-of-evolutional endogenous influence – an activity of intelligent creatures – acts as “deus ex machine”, which pushes once the process to another direction and walks off stage. Exogenous catastrophic events are present in this genre much more, but their role is the same.
On the opportunity of radical long-term change of evolutionary process Sergey Pereslegin had wrote in his article “What is enough for Herodotus, is not enough for Herostrate” (2002). Interesting ideas about other evolutionary mechanisms had been proposed by Igor Kraj in articles in “Mir Fantastiky” magazine (“Alien. Beasts of Other Worlds”, #5/2017; “Ant Forest and Talking Beasts”, #8/2017). We can only hope that any of these ideas will be developed to high-grade speculative biological project.

Civilizations in the geological past of the Earth

The question put above can be addressed also to the past: if occurrence of intelligence and civilization changes qualitatively the mechanism of evolution, could any other, inhuman civilizations exist in the geological past of the Earth? Oddly enough, this theme was developed by many authors even if we exclude from consideration a huge selection of occult and esoteric literature and writings of supernatural horror genre.

The authors, who answer the put question affirmatively, offer one of three variants. The first one: the missed inhuman civilization existed not for long, has reached a low level of development and all traces of its existence have disappeared in depth of time. A typical example of such scenario is Stephen Baxter’s story “Hunters of Pangea”. He depicts a culture of intelligent dinosaurs related to Ornitholestes, which, having improved properly hunting technique, had exhausted megafauna of their epoch (represented by large sauropods) and had become extinct after it. All material traces of their activity had been made of nondurable materials and had decayed, not having waited for paleontologists of our time. The story does not answer the question, why medium-sized dinosaurs survived, and already after its writing paleontologists have discovered that sauropods felt rather good also in cretaceous, however it reflects the basic idea very well.

The second variant implies that pre-human civilizations were one of the reasons of mass extinction events. In the novel “The Dawn on the Planet Earth” by Svyatoslav Loginov intelligent dinosaurs have destroyed their whole species, having caused a global cooling as a result of their economic activities, and parallel extinction in the seas and oceans became a consequence of their desperate attempts to stop this process. Trends of global threats choice change, and in recent article “The Silurian hypothesis” by Gavin A. Schmidt and Adam Frank, among other, an attempt (quite speculative) to link activity of intelligent creatures and Eocene thermal maximum is done.
Third scenario places missed (or sustained) civilization in the places practically inaccessible to modern humans: in depths of ocean, on the grounds flooded nowadays, under the ice of Antarctica and Greenland. This direction is so intensively worked on by esoterics and Lovecraft’s followers that writings with the claim for scientific character seldom appear here. One rare example known to authors is a remarkable essay “Gods of Salt” representing the civilization of intelligent elephants ostensibly existed during the Ice age at the bottom of Mediterranean Sea, which represented the salt desert in that epoch. Also in Herbert G. Wells’ story “In the Abyss” the meeting of the main character, the researcher of ocean depths, which is going down to ocean bottom in bathysphere, with underwater intelligent creatures and their civilization is described.
Here, actually, variants are over. One of authors of present article had tried to consider in his blog the problem on how possible is that the civilization existed in the geological past will not leave the traces which have reached up to now. The conclusion appeared discouraging (and quite in trend of the above-mentioned works): every society having developed an industry will inevitably render an appreciable influence on the world around – at first on ranges of live organisms and structure of ecosystems, and later to all near-surface geospheres of the Earth. Therefore, most likely, we are first here.

Limiting and other physics

Summarizing a definition of life, we have the right to put the question: in what degree the chemistry as such is obligatory for it. It is theoretically possible to present the complex nonequilibrium informational systems functioning on the different material substratum. The example of such “organism” had been proposed by Arthur Clarke in his well-known story “Out from the Sun”. Aliens from Peter Watts’ “Blindsight” also live in rather specific environment deadly for any terrestrial organism, and Robert L. Forward in his novel “Dragon’s egg” (not translated to Russian) pictures the life based on strong nuclear interaction and existing on the surface of the neutron star.
Australian sci-fi writer Greg Egan goes further, and in such writings as “Orthogonal” series and “Dichronauts” he begins to change base physical concepts – for example, space-time dimension. It is no wonder that the most basic displays of life in such world begin to work in another way.
Formally, writings where really working force represents any manifestations of magic also belong to the subgenre of other physics. As a rule, at this direction we get banal fantasy, but there are also more interesting variants. As an example, it is possible to mention some objects described in the collective online project “SCP Foundation”, such as SCP-1112 “Shadow Play” or SCP-407 “The Song of Genesis”. Authors of some other objects of the present project begin modifying of basic logic categories (see, for example, SCP-1303-RU “Underside” (link to Russian part of the project)), but live (are they?) creatures existing in such conditions, perhaps, lay beyond the widest framework of speculative biology.

Of course, the present thematic directions may be met not only in “pure” condition, but they also mix up with each other. In “Alltomorrows” we see, how the potential of human evolution is expressed in various conditions (on different planets), but thus the author makes a fantastic assumption about artificial intelligent intrusion of alien race at one of the previous stages of human evolution. Genetic manipulations are supposed by D. Dixon in the book “Man After Man”, but there the host force intruding the process of evolution is also of human nature. In the Stephen Baxter’s “Evolution” novel, reader finds “cryptopaleontology” in the story about the past epochs, and the description of evolution of biosphere and humans in the future, down to the decline of life on the Earth.
Elements of speculative biology may be met also in popular scientific literature as an element vivifying a narration and enabling to understand better the essence of the described phenomenon. In two-volume book “Un-missed Link” (2017) Russian anthropologist Stanislav Drobyshevsky frequently addresses to such reception during the discussion of features of people and human evolution. He invites the reader to imagine how the modern world would look, if some events of evolution of large groups of live organisms in general, or of anthropogenesis in particular have a different development – for example, if terrestrial vertebrates would descend from eight-fingered ancestors or if in parallel to people descendants of Gigantopithecus would have got an intelligence. In an epilogue the author mentions a theme of human evolution in the future, and offers some possible scenarios of course of events though he highlights them not so detailed, as it takes place in D. Dixon’s book, for example.
With all variety of thematic directions of speculative biology heroes of projects are mainly animals, among them the most popular ones are vertebrates, and indisputable favorites are mammals and birds. Maybe, it takes place because they are most attractive in the eyes of the basic audience – as a rule, not too experienced in biology and showing interest to the project at the level of personal sympathies and antipathies. It is possible also, that it is all because of some kind of “the founder effect”: first books in speculative biology field, “The Snouters: Form and Life of Rhinogradentia” and “After Man: A Zoology of the Future” told mainly about mammals and birds. Other vertebrates, not to mention invertebrates, get much less attention, though they are not less interesting from the point of view of adaptations to survival, and are equally important components of ecosystems. Moreover, even lesser attention has got to those ones, which are not able to move, and have no heart-stirring eyes and soft fluffy fur – to plants, fungi and bacteria. However, it is necessary to remember, that at any moment of history of life on the Earth they cooperated closely with animals, and frequently determined directions of their evolution. For example, the evolutionary success of insects appeared possible only in the union with flowering plants, and productive steppes represent the result of joint evolution of cereals and herbivorous mammals. In all fairness, it is necessary to recognize that in some speculative biological projects invertebrates, plants and fungi are not but that mentioned, but their presence is insufficient for their immense role in natural communities. Probably, these are expences of a target audience – macro world is closer to us, than micro world, and something warm and fluffy causes the greater response in hearts of readers, rather than scaly, prickly or mucous one. It would be desirable to hope, that among authors of speculative biological projects there will be more those people, who can tell interestingly about those ones, which people usually love not so much.

VI. What is this all for?

It is rather probable, that in the world a whole set of skeptics may be found, that, having read all written above, will ask themselves a question: what on Earth is this all for? It is a good question, which demands the detailed answer.
First, I shall allow myself citing of small quotation from blog of British zoologist, the expert in tetrapods Darren Naish. It was an article describing “Squamozoic” project – a hypothetical world where after dinosaurs squamates (lizards and snakes) became a dominant group of vertebrates. There author has expressed the opinion on the usefulness of speculative biology very extensively:

When talking about practical application of this genre it is necessary to note primarily, that the speculative biology is an independent genre of literary and artistic creation. If such genre exists, it means, that in the world many people exist, to which the present theme is interesting. On the present moment a lot of detectives, dime-store novels, love novels or space sci-fi is already written, but each year new writings of these genres – both successful, and not so – are born. And if “speculative evolution” genre has stably its admirers, there are also authors with new original ideas. Therefore, it is not necessary to deny writings on this theme in their right to exist – speculative biology has such right in the same degree, as other literary genres. Whether there products of the present theme will be interesting to readers – it is already fully and completely care of the author. However, if the author has found the reader to whom reading of works of the present subjects delivers pleasure – so why not? For example, Dougal Dixon’s book “After Man…” was republished many times, and every time readers greeted excitedly its new edition. Nevertheless, it had been written about forty years ago.
Being on the border of biological sciences, speculative biology has some predictive power, but at the level only hardly greater, than simple concurrence. Of course, it concerns not to all themes, which supporters of the present genre use in their work. The future is closed for us at least because it has not come yet, and time intervals which speculative biology operates will hardly enable authors to live up to the time when events described by them will happen, and to be convinced in their (in)correctness. However, nothing prevents authors to make predictions relatively to events and previously unknown details of the past. The most known example of such kind is a discovery in Cambrian sediments of filtering representatives of family Cetiocaridae from the extinct class Dinocaridida. The opportunity of their existence had been proposed in the book “All Your Yesterdays” (2013), where picture by J. Meszaros representing a supposed pelagic representative of Dinocaridida, a plankton filer-feeder, was shown. In the book, an assumed group it belonged to had been named as Ceticaridae. Later, in 2017, it was found out, that real earlier discovered Dinocaridid species Tamisiocaris had the similar type of filtering apparatus. The idea from the book has predicted the appearance of the discovered creature so precisely, that for naming of new family, where it was classified, name Cetiocaridae had been used – it is a direct reference to the book contents.

Speculative biology has great potential as the pedagogic tool enabling students of various ages acquiring in the entertaining form principles of evolution, evolutionary phenomena, relationships of cause and effect between the phenomena, and also to understand a role of an environment in formation of shape of animals. Speculative biology operating invented examples allows to “unlink” the biological phenomenon from a textbook example on which it is traditionally taught and to check up how students can apply knowledge about it in a new situation – for example, during the development and defense of the own project of speculative biological theme.
Speculative biology has great potential for popularization of evolutionary ideas from the pedagogical point of view. Depending on the level of schooling of students, receptions of use of speculative biology in education will differ.
At the initial stage, during the work with low-skilled primary-school pupils, they learn about fauna and flora of the past geological epochs of the Earth. In order to sum up the idea about change of the organic world of the Earth in time teacher can offer them to make some working groups and to invent the independent project supplied with illustrations or maquettes, and with descriptions of the developed ideas. Thus teacher specifies initial parameters of changes (based of scientific forecasts), locations (continents, oceans, etc.), or proposes to develop different scenarios of the future.
At more profound studying of biology in secondary school, when pupils have learned a sufficient biological knowledge, it is possible to propose them development of their own projects with the subsequent defense – a substantiation of choice of ancestral group, directions of evolution and features of shapes of descendants. Thus, pupils show fluency in mastery of the acquired material and skills of its extrapolation to earlier unknown phenomena. At the present stage, pupils can pay attention only to one group of live organisms taken separately and to model probable shape of the creatures descending from the same ancestor, but adapted to different environments (modeling of real process of adaptive radiation).
In high school and in higher educational institutions use of elements of speculative biology in educational process at more profound level is possible. At this stage, students learn about mechanisms, phenomena and principles of process of evolution. During the development of their project, its participants gather the information on long-term forecasts of climatic changes, changes of position of continents etc. on their own, and define independently the future conditions of development of events, on which background an evolution of the chosen groups of live organisms runs. Projects are presented by developers, during their defense the substantiation of the chosen directions of evolution and features of shape of the developed kinds of live organisms are done with use of the knowledge got during the learning of course of general biology and theory of evolution.
Speculative biology can represent perfect tool of popularization of wildlife protection. The picture of the world lacking creatures inhabited it for millions years and no longer existing on fault of humans sets the reader thinking about our place in nature, and about consequences of the way of development chosen by our civilization. The image of human as “a king of nature” appeared in the bowels of Christian religion, but being come off from its worldview bases, it has turned to frightening image of a creature seeding destruction and devastation in nature and looking like inept journeyman decided to repair expensive watch with sophisticated mechanism by means of sledge hammer and chisel. However, at the moment of extrapolation of modern tendencies of development of our civilization to more or less far future, the veneer falls down from this “king”, and in the near future we see humans persisted on polluted planet surrounded by rather unenviable neighbors – rats, crows and cockroaches. And then speculative biology shows us frightening pictures of the new world being a continuation of existing tendencies. Predatory rat-leopards drive on trees the degenerated descendants of humans lost their intelligence, and furious mouseraptors pasture herds of giant elephant-like human descendants in Stephen Baxter’s “Evolution” novel. In Peter Ward’s book “Future Evolution” birds – cooperative hunters of corvid family prey large animals at the extensive dumps left by people a long time ago. In Wayne Barlowe’s book “Expedition” the narration about diverse and untouched world of an another's planet goes on behalf of the person living on the ruined Earth which natural resources were looted, and the irreparable damage is put to nature as a result of destructive activity of people. It would be desirable to hope that similar pictures will enable at least somehow to “reach out” the consciousness of people, and will force them to understand that the appearance of far future is forming already today, and even right now.
One more field where graphic technique of speculative biology can be used is science fiction. It is useful for sci-fi writers and scriptwriters of sci-fi films to know about techniques and methods of speculative biology genre as the worlds represented by them frequently are nonfunctional, and even simply absurd from the point of view of biology. In this case, film or the book will considerably lose in its emotional influence on target audience. In modern culture, nevertheless there are fine examples of other kind representing the invented world as functional and natural from the point of view of biology. James Cameron’s “Avatar” and “The Phantom Menace” of famous “Star Wars” saga are those. Graphic opportunities of modern technologies enable to embody the most fantastic images on screen; therefore we should to wish cinema masters to reflect more carefully about ecological and biological side of the pictured fantastic worlds instead of about technical opportunities of their embodiment.
It doesn’t matter how the imagined world embodied in the book, web page or cinema screen looks; it is necessary always to remember the most important principle of speculative biology – think like evolution does.

The present review does not apply for completeness and is open for discussion and additions. You can send your opinions and propositions on a theme to this email:


	Above: Graham, crush-resistant human (source: Meet Graham) Left: hypothetical intelligent dinosauroid by Dale Alan Russell (source: Internet)


Pithecanthropus – Ernst Haeckel’s painting from the collection of Friedrich-Schiller University of Jena (source: Friedrich-Schiller University of Jena)	Proavis – a hypothetical ancestor of birds. Gerhard Heilmann’s picture from the book “The Origin of Birds” (1926) (source: Tetzoo.com)


	Above: picture by Monique Steele – biologically correct deep-water version of Disney’s Little Mermaid (source: Buzz Feed) Left: a predatory snouter species Tyrannonasus imperator from Gerolf Steiner’s book “The Snouters: Form and Life of Rhinogradentia” (source: “The Snouters: Form and Life of Rhinogradentia”)


Human-animal hybrids – monstrous offshoot of biotechnologies created by imagination of Dougal Dixon – of course, will hardly ever appear, but the idea incorporated in them is worthy much greater attention, than it is given to it. (source: Weintraub P. “Visions of man evolved” / “Omni” #11/1982)


Hypothetical Ceticaris. Author: John Meszaros (source: “All Your Yesterdays”)	Reconstruction of Cambrian Tamisiocaris. Author: Robert Nicholls (source: Paleocreations)