The woodclimber and armadrail stronghold
Woodclimbers and armadrails, flightless birds with specialized lifestyles, have managed to survive despite the challenges posed by global cooling and the disappearance of dense forests. While they have lost most of their past ecological diversity, both lineages are still present and widespread in Antarctica, particularly in the coldvanna region.
The ramos, a subgroup of woodclimbers, have adapted to a less arboreal and more scansorial lifestyle. They are small birds, weighing only a few kilograms, well-suited for climbing trees but also capable of foraging on the ground. Three species of ramos exist, primarily inhabiting the open woodlands of northern Neopolarica. The thicket ramo (Geobuxiornis pedemontanus), for instance, is found in smaller woody plants like those in the montane thickets of the trample steppe. Active year-round, they feed mainly on seeds and bark, serving as important seed dispersers for brumble trees.
Compared to their woodclimber ancestors, ramos have shorter but stockier legs and longer feet to move better on snow and reduce heat loss. They can form sizable colonies and migrate together in search of food, covering several kilometers per day. Ramos have a strong bite force and can defend against predators by producing a toxin that covers their plumage. Interestingly, this toxin is recycled from poisonous species of doorpeas, providing both food and defense for the ramos: a similar adaptation is observed in the holocenic pitohui.
To prevent heat loss, ramos, like other cold-adapted endothermic animals, have a countercurrent heat exchange system to maintain warm core body temperature. A similar adaptation can be observed in the flufflescute (Plumicollis relictus), the only surviving species of armadrail. Despite not favoring sub-freezing temperatures, flufflescutes can be found even in the core of the trample steppe, especially during summer. They hibernate during the cold season, finding refuge in caves or among the thickets of doorpeas. Unlike their highly scuted extinct relatives, flufflescutes have small dermal plates covered by thick plumage to retain heat. While specialized radiations of armadrails struggled to cope with rapid cooling, the more generalist flufflescutes were able to survive and thrive.
Consuming a significant percentage of carrion, they possess a keen sense of smell unusual for a bird. But that's just one of the several oddities that this unique group of birds has evolved and, hopefully, will evolve. Their future, like many others organisms, is left to chance... and luck.
