Djihauti

The Djihauti is an organism that is perhaps best described as an animal that does not seem comfortable in its own body. Despite a somewhat antelope-like appearance, it has neither the style, nor the grace (though it has a funny face). When it walks, it seems like the single, huge frontleg is simply way too long for its hindlegs to catch up, leading to an awkward gait where the organism can seemingly only move by slowly inching its way forward. Instead of a gracile ungulate, its methodical, tank-like movements remind one more of a crab than anything else. 

Catching a djihauti then, whether you be a predator or naturalist, would then seem like an easy task. Just grab it by the neck like a duck and walk off with it. But in reality you would be eating dust before you even laid a single finger on it. Everything about Mars is deceptive, including its wildlife. Djihauti is the embodiment of Sun Tzu’s maxim of needing to appear weak when you are strong and its strengths are only revealed through careful observation. Marvel at its extraordinarily long neck, with which it gazes high above the savannah vegetation. Its double head-crest is studded with multiple eyes on both sides, which are asynchronously replaced one at a time, so that it never loses its large field of vision. Its large antennae can pick up even minor smells and vibrations in the air. This creature can sense you coming long before you are even aware of its presence. 

And when you do manage to sneak up on it, it will pull its greatest trick. The long forelimb, which at first glance seemed like a liability, will suddenly catapult the whole creature high up and far into the air like a vaulting pole. The hindlegs will catch it again on the ground and the creature will continue bounding forward with all three limbs like a mad mix of rabbit and pogo-stick.

When not concerned with evading predators, djihauti lead rather unassuming lives. Inhabiting the Hellas savannah, they largely feed on tall-growing vegetation, such as scale-tree-needles, which they strip off with their beak-like jaw. Between the jaw-joint and the eye-prongs, the skull is strangely elongated and dissection has revealed that inside this tube-like part lies a rasping tongue which apparently helps grind up the food against a roughened palate. Unlike some of their extinct relatives, all modern onychognaths lack true teeth, so this arrangement seems to have evolved as a replacement for molars. After the grind, the bolus is swallowed and digested in the large gut which gives this animal such a barrel-chested appearance.

Djihauti are gregarious and seem to have evolved various forms of visual communication. Most obvious is the stretch of skin that spans between the two eye-crests. They are able to change its colour from a mild blue to a deep violet, though the exact meaning of this signal is so far unknown. When in groups, djihauti rotate their head a lot, like flagposts, which may be a way for them to better flaunt their skull-sail. Also prominent are the long, ribbon-like scales which grow off the animal's back almost like a feather-wheel. Although a role in thermoregulation has been proposed, most  signs point towards it being a pure display feature used during mating. 

Djihauti like associating with ushabtis, often browsing together. Ushabtis are much taller than djihautis and therefore even better at spotting dangers at far-out distances, so this relationship likely evolved as a form of protection. Ushabtis can also reach into taller canopies and the tripods like feeding on the debris that falls onto the ground when the bipeds rip out leaves and branches from trees. Djihauti can in turn emit a loud warning call with their spiracles when sensing danger, so the benefits from this relationship may be mutual. On the other hand, ushabtis do not seem to care much about their neighbours' wellbeing. Juvenile ushabtis can sometimes be observed using djihauti as "playthings", violently kicking and tossing them around with no warning or just generally bullying them. It is possible that this behaviour is caused by hormonal changes in the youngsters that lead to aggressive behaviour that needs to be vented. Djihauti in turn have no qualms about scavenging the corpses of dead ushabtis (or other animals in general), despite being herbivores. One has to make use of every resource available if one is to survive on this and other worlds.

Rhinoceros Warhoon

Archaeocephalians come in many forms, one of the most distinctive perhaps being the rhinoceros warhoon (Rambisaurus stamperi). Why it has that common name is obvious. The front part of the cephalon, the rhinotecum, is not just radically elongated, but also curves upward to form a sort of horn. What exactly this horn is used for is unfortunately not entirely known, despite extensive observation of this species. Kirkhope’s most extensive study so far has concluded that the horn serves a solely visual function, being basically a flagpost that the warhoon uses to flap and flutter its antennae from, either as a warning or mating display. Some accounts do, however, mention warhoons using their horns for interspecific pushing-matches, very much like stag beetles on Earth, which is sometimes stated as a fact in pop-science books. But these accounts are purely anecdotal and this behaviour has yet to be confirmed in a scientific context.

Rhinoceros warhoons mainly inhabit the dry slopes and shrublands surrounding the western Tharsis plateau. They are quite hardy organisms adapted for tough times. A large part of their gut is dedicated towards storing water, much like a camel, and their thick hide and osteoderms are excellent at preventing evaporation. They are extreme omnivores, their robust cheliceres allowing them to bite through the hard skin of succulent flora, as well as splitting the bones of any animals smaller than them. On occasion they have been observed lapping up bone-marrow with their tongue or even grinding up certain minerals. Their skin is also thick enough to allow them to feed on the predatory red weeds without being stung by their syringe-like urticating hairs.

Characteristic for the warhoons is a dorsal armour composed of multiple osteoderms, which may serve multiple functions. It obviously provides protection from certain mountain predators, such as smaller ballousaurs, but may also serve as a mineral storage or anchorage for certain muscles. Interestingly, the osteoderms are strongly infused with silicon dioxide. This has been interpreted as a form of protection against UV radiation, which poses a bigger danger on Mars than on Earth, especially at the high elevations that the warhoon lives on, as the lower amounts of oxygen on the planet also mean a weaker ozone layer. Silicon dioxide, in other words glass, is very good at blocking at least UVB rays.

On the topic of siliceous bodyparts, warhoons exhibit multiocully, meaning they have more than one pair of eyes. This is exhibited by multiple different onychognath groups, which could mean that it either was beneficial enough to convergently evolve or may actually be the ancestral trait. The benefit is obvious, as onychognath eyes are solid and are asymmetrically shed and regrown to get rid of scratches. The more eyes one has, the less the vision is impaired during these replacements.

Compared to other Martian animals, relatively much is known about the reproduction of the rhinoceros warhoon, thanks to Kirkhope’s work. The mating individuals determine impregnation through antennae-displays and head-nodding, upon which internal fertilization follows. Warhoons are viviparous and develop multiple uterine eggs, but usually only one or two of these eggs fully develops, nourishing itself on the yolk of the surrounding eggs once it has used up its own. Pregnancy can last up to one or two Martian years, depending on the altitude and availability of food, the warhoon being able to pause the development of its embryos if conditions are inconvenient. Once born, the young are fully developed and capable of living on their own.

Rhinoceros warhoons are often noted for their resemblance to the Antennarhynchi, a group of archaeocephalian tagmasaurs from the Cydonian period, to which the famous Tapinotherium and the Glyptosauria belonged. These likewise possessed an upturned rhinotecum and extensive body-armour, though they walked on erect legs instead of splayed ones and were the size of military vehicles. But this resemblance seems to be entirely convergent, as the finer skeletal anatomy of Rambisaurus shows that it is closely related to modern, lizardine onychognaths like the tynus (Sivgin 2345). Nonetheless, studying the function of the warhoon’s horn may allow insight into how these extinct aliens may have used theirs, as similarity in form likely implies similarity in function.

References:

• Kirkhope, David: Life cycle and Ecology of the Rhinoceros Warhoon, in: Areobiology, 195, 2294, p. 94 – 108.
• Sivgin, T.K.: Life on a Dead Planet. The first 3 billion years of Evolution on Mars, Zürich 2345.