Grandiose Gigagret

Though the group overall is now less specious than it once was, the aukvultures of the late hothouse include a widely diverse collection of species adapted to very different niches in the ecosystem. The only entirely flightless species, and the heaviest aukvulture of all time, can be found in the late hothouse - and the same animal holds both titles. A descendant of the imposing awegull whose ancestors specialized over many millions of years as shoreline predators of aquatic life, the grandiose gigagret breaks all records and expectations of their group.

Gigagrets evolved in the middle hothouse, around 10 million years ago, in the early upperglades. They were a branch of awegulls that adapted from upland plain habitats into more open marshes as forests spread over the landscape, and they became tall wading predators which hunted aquatic prey near shore. Earlier forms remained powerful flyers, averaging 6-10 feet in height. Today all more basal relatives have died out, having never been wildly successful.  But the single surviving species is the most impressive: it is gigantic - as tall as 16 feet, and weighing almost a ton - and it has lost its wing feathers entirely, not only in adulthood but right from infancy. As gigagrets grew larger, their feathers became more vulnerable to damage during molt, being prone to snag and break off as the animal waded on all fours in deep, vegetated water, as well as to become waterlogged and heavy, meaning such birds could only take flight after a prolonged period drying themselves off. Eventually, they were large enough that they found little benefit to being able to fly at all - all of their food was found in the marshes, and they lacked predators. Adults would eventually lose most of their wing plumage over time due to damage with little harm to their survival, with chicks being able to fly initially, much like the distantly-related giraffowl. But a random mutation which affected the development of their wing plumage, turning feathers into scale-like scutes as occurs in the legs of most avians, later provided a fitness boost by preventing the waste of energy from trying to grow new flight feathers as well as leaving their front limbs more streamlined and reducing places for aquatic parasites to hide. The living grandiose gigagret has no wing feathers at all as a result, as this mutation has now become dominant throughout the entire species, giving them smooth, scaly forelegs that closely resemble their hind limbs - and allowing their wing finger to become smaller and vestigial, kept tightly folded along their wrists. As their chicks can no longer fly either, parental care has to be initially strong, and young often cling to the parents' back as they hunt for their first few months.

Grandiose gigagrets are still wading predators; their great height lets them stride into calm water as deep as seven feet to hunt, and partially solidified bones increase their density and prevent them from floating away easily in currents. Their preferred habitat is open wetland, where they can stride through slow-moving waterways and catch large fish and snark prey by patiently waiting and striking by ambush. They try to grasp prey in their hooked wing claw, which are so large that the adult often walks on its knuckles to keep them out of the way on land, though it will stand on its palms to spread out its weight on soggy ground. They pull captured prey out of the water, then secure a firm hold in their serrated, notched bills so that they can then tear swallowable pieces off from the kill with their claws. Gigagrets overlap in the extreme north of their range with another large fishing predator, the much shorter but not quite lighter arctic snagglejaw, and compete there for some of the same prey, but the two species differ in their habitat preferences: snagglejaws swim well and can hunt in deep, flowing water away from land, but gigagrets can't swim much at all, being too tall and dense to float, and so are limited to near-shore environments at all times, preferring marshes to lakes and rivers. While snagglejaws can feed far out to sea in the polar basin, grandiose gigagrets must return to land to easily tear prey apart and consume it. But in turn, the gigagret can walk on land far better than the snagglejaw, and so can engage in over-land movements between isolated wetlands far more effectively - as well as to occasionally hunt on land in one specific place, the nightforest.

In the darkness of the polar winter, gigagrets stride silently along the shore in search of prey, like ghosts in the night.

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Along the edge of the nightforest, in an ever-misty jungle where the tallest trees in the world give way to wide sandy beaches on the shore of the polar basin, is the one place that the gigagret can be seen to leave the water entirely and come inland to hunt. Why it does so only here is not entirely known, but it may be related to the rapid rise in elevation as the arctic plateau descends into the basin, putting two very different habitats next to each other in a way not occurring elsewhere. Here - especially in the spring, when the biggest fish retreat into the darker depths of the lake - these towering predators can be seen to enter the forest in search of land-living prey.  A low layer of clouds shrouds the forest throughout the winter and into the spring as water rises from the basin, and provides moisture to the canopies of the forest thousands of feet above the ground. The gigagrets stride quietly through it, like sinister spirits through the gloom, taking advantage of this fog to obscure their silhouettes and letting them sneak up on and catch on anything unwary in the undergrowth: even prey as large as unicorns is fair game, and will be wrestled to the ground and killed by ripping out their throats. Juveniles, with their hooked claws, are even more terrestrial than the adult not only here but also in the flood forest, and will frequently ascend trees to find food and avoid ground-dwelling predators which would not bother the mature adult. This can bring them into contact with new dangers above ground, however - ruffed rasps will readily hunt these youngsters. It is a strange interaction of species that would not seem likely to ever meet, but which come together only in this part of the world where two very different worlds collide.