Oceanic Pikebird

The pikebirds were a widespread and successful clade of eargilled, aquamorph metamorph birds that arose in the late Pangeacene. As typical eargills, they were neotenic and fully aquatic birds that never developed a feathered or flighted adult life stage, instead reaching sexual maturity while still in an aquatic, larval condition. Never developing functional lungs but growing much too large to breathe through their skin alone, respiration now occurred via intake of water through the mouth and expulsion of it through a hollowed-out ear canal lined with vascularized tissue. Despite being neotenic, their actual bodyplans extremely specialized to life in water and became extremely convergent with fishes, scarcely resembling the tadpole-like ancestral condition for aquatic metamorph larvae.

Eargills today are widespread through the oceans, competing effectively with the true ray-finned fishes though not quite outnumbering them in species count, as ray-finned fishes still exhibit several superior adaptations, particular in the flexibility of their much more malleable mouths. All eargills reproduce through small, shellless eggs that may be broadcast through the water column and externally fertilized, or fertilized internally before being deposited. Pikebirds are one group which utilize the latter strategy, and so unlike most eargills pikebirds can have a much clearer idea of who fathered which offspring. This has led to the oceanic pikebird being highly territorial and polygamous. Living in the thickly vegetated waters of the equatorial sea during the middle Ultimocene, males aggressively mark out and defend territories in the tangles of aquatic vegetation in which a number of smaller females shelter. By keeping away other males, each male can be relatively sure that only his genes are being passed on via the females. Though the species shows no particular parental care, this certainly of parentage has resulted in the species no longer being cannibalistic, and the juveniles may shelter around the much larger adults for protection. This evolutionary strategy has backfired in one way, however, in that because none of the adults are cannibalistic but neither do they recognize their own offspring, young oceanic pikebirds actually move freely between territories and do not associate with only their parents, meaning that it's quite likely many if not most of the juveniles allowed to live within a male's territory are not his own young at all.

Pikebirds evolved as freshwater, riverine predators and it is still rare for any species to have colonized the ocean. But as rivers largely freeze over inland while meanwhile the sea level drops and vegetation grows thicker, providing suitable cover for this highly-specialized ambush hunter, it is likely more species will adapt to the higher salinity and move out into the ocean. Here they find abundant prey but also much larger predators, which have already led the oceanic pikebird toward gigantism. So long as food remains abundant, it is probable that these most fish-like of birds will continue to grow as large as resources allow in this rich and productive new habitat.