I. Kraj "Alien. Beasts of other worlds"
Main Neocene

How animals from other planets can look? Would pathbreakers meet casual combinations of retractable claws, pincers and beaks, or, on the contrary, would xenomorphs differ from Earth predators only in strip patterns on skin?


Beasts of Other Worlds

Text by Igor Kraj
(article is published here in authorial version with pictures sent by author himself; the magazine version can be seen here)

- Should we design for sovereign new breeds of animals,
extremely furious and predatory, whether not so?!

Stanislav Lem “The second travel,
or the Offer of king Cruelus”.

It is simple to imagine alien monster. If it would not be desirable to strain at all, it is enough to take of something habitual, terrestrial and to increase its size for impressiveness. According the tradition spider is used for this purpose… But it is better, of course, to work hardly, having combined a creature of separate details (it is desirable to take incompatible ones) borrowed at various classes and even phyla of animals. Tentacles and superfluous pairs of legs are welcomed. If to apply some really creative decisions (not asked a question on their expediency), it will turn out very good. The Alien will appear, from the same Ridley Scott’s film.

Ice monsters

If to use a serious approach to a problem, we need to start not from xenomorph, but from the planet, whence it comes. Similar problems assume similar solutions. It is enough to recollect shark, tuna, Ichthyosaurus and dolphin, which despite of huge distinctions in origin and internal structure look approximately equally – like it is necessary to look to a predator hunting in thickness of water. It means, for occurrence of never-before-seen on the Earth, amazing our imagination and truly alien forms of life conditions are also required not less alien and original. And already at this stage science clips wings of imagination, for though the universe is boundless, the choice of conditions in it is limited.

It is simple task to “design” an animal in which metabolism the place
of water would be taken by sulfuric acid. It is enough to replace oxygen
with sulfur in DNA. But where is it possible to find a suitable planet with
acid oceans for its occurrence?

Most likely the world having the advanced biosphere will have much in common with our own one. Any alternatives appear either physically impossible or obviously adverse. And more often they are even not true “alternatives” at all. So, there is no base to doubt that life is possible in subglacial oceans of Jove satellites. It is because on the Earth it not only exists in absolute darkness at huge pressure and absence of oxygen, but also even had arisen in such conditions, as it is considered nowadays. Conditions suitable, as we again know by experience of our own planet, only for extremophilic bacteria. Thus, we already have the exhaustive information about the monsters presumably occupying gloomy abysses of Europe. In case of their invasion to the Earth the fire and laser weapon will appear completely useless. Boiling will also not help. Ultra-violet lamp and water fluorination will allow to win the war of the worlds in a test tube.

In trenches at the ocean bottom lacking light and oxygen it is possible to find only bacteria
surviving due to chemosynthesis and not numerous immigrants from areas of more favorable
conditions. But even they are only representatives of the evolutionary bottom not higher
than worms by rank.

It is necessary to search for really alien life on planets too hot or too cold for existence of water in liquid phase on them. And the fiery worlds, probably, may be rejected at once as the high temperature is the natural enemy of complex molecules. With icy celestial bodies on which oceans of liquid gases splash, not all is so hopeless.
At the temperature estimated in tens Kelvin degrees very interesting effects of cryochemical synthesis express. On the one hand, the cold slows down reactions, but on the other hand, even the compounds most unstable and non-persistent in usual conditions get an opportunity to exist. Very weak chemical connections imperceptible at room temperature build atoms in complex structures.
Certainly, a cryosynthesis-based life is very extravagant hypothesis, which plausibility the science is not capable even to estimate at the given stage. But if such opportunity is realized, it will result in rather unusual animals and the plants existing as if in different time stream. As the intensity of metabolism, after all, will be very low, the furious predator from the point of view of speed appears similar to a baobab. Also it is not necessary to speak about plants at all. Only the refined analysis will allow distinguishing them from mineral formations. Because of low rate of alternation of generations and also of slow evolution cryobionts in any case will remain primitive creatures. But thus only big and even huge size will allow them reducing to a minimum losses of energy produced in an organism.

At Triton – the satellite of Neptune – the seas of liquid nitrogen lapped about a billion years ago.

Something similar – namely, ice “Burmese forest” on Titan – is described by Stanislav Lem in the novel “Fiasco”. It is necessary to note that descent vehicle “Huygens” has not fixed the existence of impressive ice vegetation at the surface of the largest satellite of Saturn. But if to admit that life on Titan exists and has already got from methane “waters” to “land” consisting of ammonium-water ice, it is quite possible to assume that identical rounded “stones” seen on photos are cryo-plants.

The Alien World

Acid blood of Aliens is not a norm for biosphere of their native world.
Otherwise, acid spittles would be senseless as the weapon. Rather, it is
a defensive mechanism: “You will never eat me without alkali!”

If to admit that “Aliens” are not created artificially by the civilization advanced in the field of genetic engineering, and have arisen in the evolutionary way, the world which had caused this species is a terrible place. It is so not because there xenomorphs with pharyngeal jaws are found. That is because in the homeland they obviously are not at top of a food pyramid, but closer to its basis. The propensity to parasitism absolutely uncharacteristic for “bosses” and enormous breeding rate of the kind justified only in conditions of necessity of compensation of huge losses testify it conclusively.
Even larvae of Aliens – “facehuggers” and “chestbursters” – are not helpless. And queen is capable to enter fight, having discarded the ovipositor… It means there is a high probability that soldiers of xenomorph beehive can’t protect “queen” and its posterity.

The Flying World

Conditions completely “unearthly” and simultaneously favorable enough may be found also at the oxygen planets. The majority of worlds presumably suitable for life discovered at present belong to the “super-Earth” class. A planet surpassing the Earth in some times in weight and having, accordingly, strong gravitation will provide itself with high probability with an atmosphere comparable in density to Venus one. It is not too good in itself. The super-power greenhouse effect can result in overheat, and the thick gaseous envelope will absorb light, interfering with photosynthesis at the surface. But in such conditions the aerostatic way of movement beloved by sci-fi writers, every second of which populates the unknown worlds with critters floating on hydrogen bubbles, appears possible. Moreover, in “heavy” world with very dense atmosphere soaring appears an extremely productive idea, hence also attractive from the evolutionary point of view.

There are reasons to believe that at least some ammonites couldn’t dive
and represented huge (up to two meters in diameter) floats.

Among the first plants will transform to bubbles filled with methane or hydrogen; floating will allow them rising to light, that is, higher than a cloudy veil. Plants will be followed inevitably by animals, which, again, will turn to live balloons. At the “greenhouse” planet the high resistance of the medium will make unprofitable flapping flight usual in terrestrial conditions. Small wings will be required to function as rudders; the work of the propeller will be carried out by “air jet propeller” modelled on squid’s water jet device.
The representation about lifeforms inhabiting “the flying world” may be given by Earth ocean. It is so, because aerostatic and hydrostatic (using a swimming bladder) movement make the similar demands to the physical arrangement. Accordingly, the shape of air beasts may be very freakish and diverse. It will have obvious shared feature – inhabitants of an atmosphere will be much larger than inhabitants of thickness of water, because gas-filled cavities will take 90% of body volume, and only the large size will allow getting strong covers and reducing to a minimum frontal resistance at flight.

One more effective way of movement at the planet with dense atmosphere is soaring
due to force of wind. For insects and small plants such variant is even more preferable
than aerostatic floating.

Certainly, at the “super-Earth” also flightless animals will be present, inhabiting planet surface turned to the “bottom” of the air ocean. As well as for other benthic inhabitants, the basic food for them will be made of corpses of those ones which had floated up hardly above than it should, then had bursted and deflated… But there is a great chance that land at the “greenhouse” planet will be absent at all. In the world rich in gases the water will be abundant; the relief of the planet as smoother, as higher is the gravitation. Most likely, the oxygen super-Earth will become “ocean planet”.
The absence of land will cause one more kind of an environment, not like non-existent on the Earth, but not playing an appreciable role and unattractive. In oceans of our planet there is a lot of plankton – animals and plants “soaring” in thickness of water and moving due to currents. Pleuston living on the surface of water, as a rule, does not form the great mass. Pleustonic plant organisms are the closest to light (that is especially actual in the gloomy world), but if the seaweed does not “anchor” at the bottom, the wind will quickly cast it ashore.
In the case when shores are absent floating on the surface instead of thickness of water becomes an obvious and best choice. The seas will become covered by masses of the bound stalks, probably, dense enough to sustain weight of arthropods and small vertebrates. And large creatures eating seaweed will turn to “live boats” doing not wish or even not capable to dive, because they have absolutely nothing to do under water. Well, and if all prey is on the surface, predators will come also to change a way of movement; they will pass to breath with atmospheric air and swimming with the minimal immersing – using the principle of speedboat or hydrofoil. Because despite of the density of atmosphere, resistance of the medium in air is less, rather than in water.

Oceanic vegetative pleuston – Sargassum algae – at the Earth is
characteristic only for the Sargasso Sea also called “sea
without shores”.

Even the fauna of “dry” and not having atmosphere of outstanding density “super-Earth” will appear unusual. Evolution of fauna will be influenced with the increased gravity complicating flapping flight and walking. At first sight the problem is solved simply – animals only must become smaller to improve the force to weight ratio. But actually it is a too serious sacrifice. Because in nature things are just simple: the larger bird gets the worm.

The characteristic feature of the animals of “heavy” worlds may be a vertical mouth.
Blue whale overturns sideways instead of lifting its huge jaw. The mouth swinging
open in sides is also more convenient for creeping creatures.*

* In due course of preparing of the article for the site another illustration had been choosen.

The first amphibians on our planet were not able to walk yet and, resting against the ground with paws similar to fins, dragged hardly on stones the belly protected by corneous plates. Only the second generation of land trailblazers had managed hardly to rise on legs, having reduced friction at movement. But if the gravity will make 2g as in Harry Harrison’s “Deathworld”, movement using four fulcrums becomes an excessive problem for primitive vertebrates. No, they will not surrender, but will simply move to domination on land in different way, having undertaken for development of progressive methods of crawling. And the “heavy” planet will turn to an empire of snake-like creatures. In other relations the biosphere will remain “earthlike”. Creeping legless animals will occupy niches of large herbivores and predators, will acquire with wool and will start to nurse their cubs with milk in proper time.

“Easy” planets

According the canon Pandora planet of “Avatar” movie has gravity 20% weaker
compared to the Earth, and 20% denser atmosphere. But the size of Pandoran
flying monsters points to the gravitation not greater than on Mars.

The opportunity of existence of “oxygen” planets having gravity about 2-3 times weaker than on the Earth seems to be doubtful. But in very favorable circumstances (outflow of gases into the space is compensated by their receipt from bowels as a result of extremely high seismic activity caused, like in case of Pandora, by tidal interactions) such situation seems to be probably. Low gravitation will not create really new and original conditions. Nevertheless, the appearance of representatives of “easy world” biosphere appears to be very impressive.
Weak gravity will make flapping flight accessible to medium-sized animals. Smaller ones will spend for movement by air no more energy, than for walking. In such situation only the largest or digging animals will not hasten to get wings. At top of food pyramid, certainly, the birds adapted to flight in the best way will appear, having an opportunity to eliminate the backlog from mammals in brain size and physical strength. The eagle weighing two hundredweights… however, it will remain an eagle. Because from the aerodynamic point of view the eagle is much more perfect, rather than flying eeriness from “Avatar”.
It is curious also, that “easy planet” will not cause land-dwelling giants. The size limit of animals is restricted not by gravitation, but by food resources.

Ancient planets

Caecilians represent the “youngest” and most perfect modification of amphibians
intended, as it is easy to understand from the shape of animal, to replace usual
worms. In “old” biospheres vertebrates will most likely supersede completely
invertebrates even from the least attractive ecological niches.

At the planet similar to the Earth evolution will inevitably go in the similar ways. And the result will depend on how far it will manage to go. If not too deep, we can familiarize with it in general not leaving our world at all – by methods of paleontology. But if evolution will go further, than at the present moment on the Earth, it will cause animals much more “alien” and unusual than in any previous case. Though it hardly probable will relate to appearance of animals.
During the last 20-30 million years evolution on the Earth gives lesser attention to the shape, focusing in the internal contents. Modern wolves are weaker compared to “dire wolves” (Canis dirus) of Pleistocene, but are much cleverer. Perfection of natural arms has completely lost sense for the wolf is capable to kill a creature much larger than it is, and thus eats voles mainly. Increase of intelligence yields the best results. The “headies” race mentioned in novels by Strugatsky brothers – intelligent canids distinguished from the wolf only in volume of skull – is most likely an authentic portrait of a predator from an ancient planet.
Forms insufficiently large to get the necessary brain size, and also reptiles, amphibians and arthropods will change much stronger, having passed to social habit of life allowing adaptation due to physical specialization of “castes”, or having joined in complex circuits of symbiosis. It is possible to imagine turtles with wasp nests in carapaces, or the social rodents having mouse-like caste for activity in wood litter, the workers equipped with gliding membrane for conquering of the top levels of the forest, the caste of digging builders and the caste of soldiers for protection and casual predation.

The amazing effect of “alieness” arises when a certain kind of animals occupies
an ecological niche obviously not intended for it. The New Zealand kiwi bird is
an imitation of insectivorous mammal.

The animals not feeling any callings neither to the higher nervous activity, nor to the organization or to symbiosis, will also find an exit. Sci-fi authors like to settle Neverlands with the polymorphic monsters shifting their shape depending on circumstances. But for change of the shape it is not required at all to steal another’s genes as it is done by Aliens race. It is possible to have some complete sets of their own ones.

After decoding of the genetic code zoological directories had to be re-written. It turned out that some species of fishes (including trouts) are capable to form up to four forms in the same reservoir, differing in appearance and a way of feeding. And even adult fishes, having got to new conditions, are capable to be transformed physically – for the best conformity to them. It is not so surprising if to remember that salmon fishes in courtship period change even the skull anatomy.

Genetic plasticity is an effective method of the adaptation. But it has its own price.
At the species changing their body structure on external conditions the abnormally
high frequency of genetic defects takes place.

Polymorphism called in scientific language “genetic plasticity” permits to one species to occupy any number of ecological niches and to adapt even to promptly changing environment. But the only restriction exists – if ancestors of this species were already adapted to it once. As it is known, in its development embryo repeats a history of its species. And some animals are able to “recall” evolutional decisions already found once. This method is effective in its own way, though only for the creatures completely relying on an instinct and not accumulating individual experience. Highly organized vertebrates will come anew to study in everything after physical transformation.


Xenomorph may have tentacles, pincers and moray’s retractable mouth. But while drawing its portrait it is impossible to neglect the aesthetic side of the question. Despite of alienness, beast from another planet will be beautiful – it doesn’t matter, is it real or successfully designed. It concerns to dangerous predators first of all. Human intuitively determines perfection and efficiency. That’s why the majority of Earth animals is seemed beautiful for us. Or, anyway, not ugly. Apart for spiders, the relation to which is predetermined by atavistic fear, exceptions of the given rule speak for themselves. Evolutionary outsiders – scavengers, parasites, underground, deep-water or obviously out-of-date creatures – are unpleasant in their appearance. Like crocodiles are. Snakes, for example, are in trend for the present. It is possible to be afraid of them, and they are completely alien to humans. But it is impossible to name them ugly.

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Further reading

Poul Anderson “Three Worlds to Conquer”
Kir Bulychov “Snow Maiden”
Arthur C. Clarke “Out of the Sun”
Michael Crichton “The Andromeda Strain”
Alexey Dneprov “The Clay God”
Arthur Conan Doyle “When the World Screamed”
Harry Harrison “Deathworld”
Fred Hoyle “The Black Cloud”
Alexey Konstantinov “Contact at Lengeven”
Alexey Tolstoy “Aelita”
Herbert George Wells “The War of the Worlds”