Southern Ptannu

Despite their unassuming appearance, which recalls wingless fowls, bennus are a quite successful group of organisms that has managed to adapt to all climate zones of Mars. One branch of this family is the cold-adapted ptannu (Bulbornis australis) which inhabits the vast tundra that stretches over much of the red planet’s southern hemisphere.

Though superficially similar to the bennus of the shrublands, the ptannu has a much more bulbous body, denser fur which extends all the way to the toes and extended tail bristles. It is also capable of completely retracting its neck into its shell, including the beak. These are all obvious adaptations towards conserving warmth, which it obviously needs for living in such a bleak landscape. Notably, the auxiliary eyes of the ptannu are much more developed than in other nothornithes, resembling much more the primary eyes atop the cranial bulge.

The life of the ptannu is strongly tied to the seasons. When the first rays of the spring sun begin to thaw the top-layer of the permafrost, the marsfowl migrate south from their winter homes back into the southern marshlands and bogs that start forming. Their characteristically white fur begins to molt and is replaced by brownish to reddish hair which helps them blend into the environment. As the ecosystem, reawakens they start feeding on what they can: Small frondlets, sporians, filulithophore-sprouts, young wanderstalks with unhardened shells, wadjet larvae, as well as tachmut and smaller onychognaths. Once the short summer begins, the ptannus enter breeding season.

Here it is fascinating to mention that ptannus are among the few Martians that can be described as good parents. When two single ptannus meet during breeding season, they usually mate for life and build a nest out in the open tundra which they protect together. How the pair of monogamous hermaphrodites determines who has to be the “mother” in the family, as in the partner that is  impregnated and has to produce the eggs, is not known, though some pairs have been observed changing their roles each season. After a few weeks, the two to seven eggs hatch into precocial young that are immediately able to follow their parents around. The parents care for them greatly, teaching them how to feed and warming them with their bodies during the cold nights.

Unlike some other tundra dwellers, ptannus do not immediately migrate north with the onset of autumn, but choose to remain for a few more months. Their fur turns white to blend in with the growing snow and the family exploits the few remaining resources that have freed up now that everyone else has left. Only during the worst parts of winter, when photosynthesis crawls to a complete halt and makes it difficult to breathe in the tundra, do the ptannus migrate northwards towards oases in the shrublands, which they seem capable of finding by pure memory alone, perhaps using certain landmarks for orientation. Their children follow them and memorize their paths, until at the end of winter they have grown mature and begin living on their own.

It was originally thought that the southern ptannu was closely related to the northern one (Bulbornis borealis, though read on), which inhabits the much smaller tundra surrounding the north pole, and that they formed a single genus. One of the first ever molecular studies done on Martian organisms has however cast serious doubt on this, finding evidence that, surprisingly, the northern ptannu is actually more closely related to the highly aberrant marsalk of the northern ice cap (Leidy 2322). This makes these two an obvious case of convergent evolution. Since the northern ptannu neither belonged to Bulbornis anymore nor was close enough to be shoved into Areoalca, it has since received its own genus, whose name has now been agreed upon to be Paraxenoalca.

References:

• Leidy, Dustin: Molecular evidence disproves ptannu monophyly, in: Nothornithology Bulletin, 14, 2322, p. 76 - 93.