Bloons

Fifty million years have passed on the small green moon of Serina since the first canaries were set free upon the land. In these long intervening years, a world was built from the barest of foundations to a diverse pallet of life today unmatched anywhere in the cosmos. The descendants of Serina's very earliest songbirds have today conquered land, air, and sea, filling an ecological vacuum in a world without other tetrapods to compete with in ways that our own world has never known.

One of the most specialized lineages birds of Serina fifty-million years PE are the Bloons. Growing to more than sixty feet (18 meters) in length and weighing up to fifteen thousand pounds (6800 kg) they are a family of gentle, herbivorous leviathans, the largest birds to have ever so far existed, which make their existences as Serina's analog to sea cows across the moons' tropical seas, where they graze upon immense undersea meadows of kelp and sea grass, eating up to a thousand pounds of it in a days' time. Several times too heavy to leave the water and with their hind limbs all but vestigial, fused to their pygostyles, these easy-going, wing-powered swimmers spend their entire lives at sea, from hatching to death. This is possible because while like all birds so far to evolve at this time, the bloons must lay hard-shelled calcified eggs - eggs that cannot survive prolonged immersion in seawater - they belong to an ingenious order of sea birds which have found a unique and exceptional method of caring for their eggs which requires no visitation to the shore in the form of mouth-brooding.

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Mouth-brooding - at its simplest meaning to protect the eggs or young from predators by hiding them in the mouth, is a relatively common behavior in many fishes and even some tetrapods. The reproductive behavior of the bloons however marks a first in birds; in these species and their relatives, it exists as a highly-derived behavior originating from an ancestral tendency to protect the young chicks from danger or keep them warm by carrying and holding them in a pouch below the bill which likely first appeared more than thirty million years ago in the bloons' pelican-like ancestors, a group aptly known as pelecanaries, long-flightless seabirds evolved from the dougal of the Anciskan Floodplains. Once this was well-established over time, it was not a large step to also hold the eggs themselves there, for being able to transport ones' unhatched young - which virtually no other bird is known to do, even though the behavior is commonplace in mammals and even crocodillians - proved a highly beneficial behavior for a large seabird which nested increasingly far from land and upon less and less stable mats of plant material in the manner of a grebe, pushed from more choice breeding locations ashore by rampant predators and competitors on the world of birds. With eggs in this situation likely to roll into the water at the slightest mishap, evolution favored those eggs both most tolerant to brief immersion, with large and buoyant air pockets and waxy eggshell cuticles less easily permeated by seawater and behaviorally, those birds which as breeding adults would still recognize their own eggs outside the perimeter of a chosen nest - which very few birds today can - and further, which were both willing and able to return lost eggs to the nest if they were to fall out.

As this novel egg retrieval behavior developed, and the parent bird's mouth evolved to be increasingly well-suited to the transport of both eggs and young - and furthermore, as one group of pouched piscivores became too large and ungainly to easily sit upon any manner of floating nest - they began to incubate their single eggs directly upon their own soft, feathered backs. By taking turns to transfer the egg between them and covering it by turning the head over their shoulder and covering it with the warm, soft skin on the underside of the throat pouch, they found a new way to provide the developing eggs with safety, warmth and humidity independent of any true nest site at all. This was effective, but for the most part required the protection of colonial breeding in isolated calm, shallow waters to truly work out, and so from here it was not long before one group was to eventually begin to hold the eggs directly inside the throat pouch at all times. This freed the adults to move freely whilst incubating and more importantly hid the vulnerable egg from predators entirely - factors which together allowed the birds to develop secondarily less colony-dependent lifestyles and to subsequently diversify greatly. Now the male simply plucked the floating eggs from the water as the female dropped them and maneuvered them safely and quickly into the pouch to incubate while still allowing him to feed himself and keep alert for predators. The egg became increasingly large and insulated by the fat and tissue of the neck it is effectively impossible to crack, for a strong enough blow to rupture it would also break the adults' neck.

Oxygenated every time the adult surfaced to breathe, kept warm and moist within the adult's body, in this way the bloons' ancestors developed a roundabout way to nurture their developing young within the safety of their bodies and to circumvent the formerly universal avian need to tend a nest on dry land. When the chick is ready to hatch the eggshell is now much too thick for it to escape without parental assistance, so it begins peeping a signal to the parent to gently crack the egg with a horny nail at the end of their bill which has adapted for just such this use. The chick can swim and feed itself from birth, but remains close by its parents for several years, generally protected by merit of their great size and highly protective nature. Adults can rear as many as three clutches in a year and as chicks do not immediately disperse may be seen to be watching clutches as many as six or sometimes more young of various ages at one time. For additional protection, adults frequently form creches with other adults of several dozen or more young, guarding them as a herd from a myriad of predators which may lurk the shallow coastal seas that the gentle giants roam in hopes of picking off a straggler similarly to many earth waterbirds. Herds of bloons are rarely organized but individual pairs mate for life and good feeding grounds can attract loosely-associated gatherings of hundreds or rarely thousands of the animals along especially fertile coastlines.

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Bloons are the most specialized member of their order at this period in time, having traded their piscivorous tendencies for a diet of green plants and algae and rarely slow-moving invertebrates, all managed by a goose-like serrated bill. Most of their relatives retain a more carnivorous diet, with diets ranging from small fishes and marine invertebrates up to large seabirds and even bloons themselves. Though they may differ greatly in appearance, size, and lifestyle, however, they can all be allied by their unique manner of internal incubation. Incubation is a joint affair, with pairs regularly transferring the precious cargo between them twice a day to feed whilst the other parent rests near the surface so as to create a calm and stable environment for its developing young.

Modern bloons have almost wholly lost their plumage and retain only a very thin layer of fuzz over their bodies, generally just a few millimeters in length. Too large and bulky to properly preen, they are instead insulated by their body fat.

Male Emperor Bloon, Partuphagus imperialis (from the Latin "Partus", meaning childbirth, and "Phagus", meaning to consume.)