The Island Wumpo

The island wumpo is a small insular population of the Proboscirostrus genus whose ancestors split from those of the woolly wumpo three million years years ago. Though also a hybrid descendant of the wump and the mammoth, island wumpos have a higher wump contribution to their genome - 60%. They are thus physically even more similar to this ancestor than is the woolly wumpo, though they have a more upright posture. They evolved when a very small number of early wump/mammoth hybrids were isolated on two small islands off the coast of the western refugial peninsula. Their ancestors likely swam the distance - some 25 miles - in a desperate search for food during an extreme cold spell. For just a few to reach land with no sense of direction to find it, it suggests many more likely drowned at sea on similarly blind journeys.

For those that succeeded in the crossing, however, the islands were a favorable environment. Similarly to those further west which support the ptarmenguin, there were no land carnivores present, and so these wumpos have never known predation. This rendered them over time docile and trusting. Though this could get them into trouble, it also meant they had none of the inherent fear of new things their relatives exhibited, and left them extremely curious. Food supply was limited by the small size of their range, but as thorngrazers - extremely poor swimmers - were absent there, the vegetation grew thicker and was primarily soft grasses instead of cactaiga, and so was more nutritious and abundant in a given area than similar plant food is upon the continent.

Island wumpos are only about a quarter as heavy as their continental counterpart, averaging just 500 lbs, an adaptation to less available food. They have slightly shorter feathering and a thinner build, with longer legs usually without complete feathering down the toes. The face is also not fully feathered, as the islands’ climate is buffered by surrounding water and so less severely cold. They live in a similar social structure of small familial units that occasionally group together and mingle with others, and herds are led by the oldest and most experienced individuals. Yet like wumps, island wumpos often split into pairs or even go out alone for days at a time. Their social bonds are not inherently weaker, but they are more comfortable being alone - the lack of carnivores in their environment likely contributes to this different behavior pattern.

The most noteworthy difference between woolly and island wumpos is cognitive. Island wumpos, like the mammoth trunkos that contributed to their ancestry, are very intelligent and near-sapient, but have not quite crossed the threshold that the woolly wumpo did half a million years after the two species’ populations split. Though island wumpos are still very social and emotionally perceptive, they are less rational and more emotional, and retain a more immature personality relative to an adult woolly wumpo as well as considerably less capacity for abstract thought. Though they too have a language of sounds used to communicate, theirs are more simplistic.

Evolving from a very small colonist group of as few as 10 adults, the founder effect is dramatically demonstrated in island wumpos. Because genetic diversity was so low in their ancestors, they have rapidly evolved distinctive appearance through genetic drift. They are also extremely resistant to inbreeding, with most harmful genes producing genetic diseases having been lost early on in the species’ evolution. All individuals of the modern species are 95% homogenous with one another; this is a similar percentage of shared genes to lines of laboratory rats bred sibling-to-sibling with no outcrossing for more than twenty generations. Yet with nearly all deleterious alleles lost from the population, this extremely low genetic diversity does not seem to negatively affect the island wumpo significantly, though its resistance to novel disease is likely worse than the mainland species. Male island wumpos have low sperm motility, yet seem adapted to this as the normal condition and do not become less fertile even after generations of close relative mating. Their reproductive rate actually exceeds that of the woolly wumpo, with sexual maturity attained many years earlier, as young as ten years of age compared to twenty.

The island wumpo has evolved very colorful facial markings, much more in line with the ancestral species than the virtually plain-colored woolly wumpo, but even more exaggerated. Unlike all of their relatives, albinism and piebaldism is completely non-existent in the island wumpo, because none of the small herd that gave rise to them were carriers for either mutation. There is a high prevalence of erythism, however - reddish, almost strawberry colored coats - as well as an even more bizarre mutation affecting plumage growth. Some island wumpos exhibit long plume-like feathers on their toes. Completely non-functional, the mutation interferes a little with rapid movement and so would probably not perpetuate anywhere predators existed. Here, however, it is only a minor inconvenience. The foot feathering is homologous with the primary feathers of flying birds’ wings, and the mutation responsible effectively modifies the hind leg with foreleg traits, making it wing-like. A similar mutation occurs in the earth pigeon, which can show fully-developed wing-like feathers along its feet under selective breeding. Yet as wumpo ancestors lost their wings some 240 million years ago, the genetic information to build flight feathers is so corrupted from disuse that the mutation now only causes long, frilly, and entirely useless mutant plumage to grow there - long, ostrich-like feathers that demonstrates what a trunko’s wings might look like if they were still there.

Due their smaller size, the calls of the island wumpo are higher-pitched than the woolly wumpo, and so fall within hearing range of smaller animals. Even if the two species were to meet again, they would not be able to speak to each other; island wumpos hearing range is much higher, and not very sensitive to extremely low tones.

The two wumpo species coming in contact again is no longer merely a hypothetical, for it has begun to occur. Their haven is no longer cut-off from the world, for sea level fall has formed a new land bridge between their islands with each other and to the continent in just the last hundred years. For the island wumpo this changed things, though not necessarily in only negative ways. They were fortunate in that the only significant predators that could threaten their species, circuagodogs, were already nearing extinction by the time the species had spread out onto Serinarcta; cutthroats and bumblebears both favor slower prey species, while carnackles generally take only smaller prey.

Thorngrazers have already begun to colonize their islands, and are beginning to alter the floral community there to match it to the mainland. Having not evolved with this competitor, the wumpo lacks the aggression and avoidance of it exhibited by the woolly wumpo. Though this could have left it vulnerable, its small size and agility renders it mostly unconcerning to both species of thorngrazers, so that it can follow the ground-clearing razorbacks and hunt the small animals that flee in their wake. And unlike the massive woolly wumpo, this species is not restricted to open grass steppe, for its much smaller size allows it to utilize the narrow pathways that are formed in the cactaiga habitat that is maintained by the feeding of the browsing nimicorn. Here they find a variety of softer herbs, sedges, seeds and the fruit of the cactaiga itself, which are at times more nutritious than the grasses of their original island habitat. Because they are less cold-hardy than the woolly wumpo, however, the island wumpo maintains a very strictly coastal distribution even as it spreads out east along the peninsula. Where the two species meet, there is curiosity but also apprehension. Island wumpos are friendly but strange to relatives that have never coexisted with another closely related species in their cultural memory. The two species interact occasionally peaceably away from feeding sites, but competition over limited food resources also means that woolly wumpos do not generally tolerate them eating their food and so the island wumpo sticks more closely to the cactaiga thickets.

Island wumpos often consider woolly wumpos highly attractive as mates as they value size and strength, as large mates often have higher social status. Morally grey hybridization has occurred rarely, though is considered socially shameful, with the wooly wumpo usually being the mother, though crosses the other way may simply be less documented. These hybrids are generally raised within normal herd society without much fuss, and are not considered unintelligent, being typical for the woolly species in all cognitive abilities. As mating with the other species is looked down upon by most of the species, herd leaders will often try to pass them off as regular woolies, which many look close enough like as infants depending on whether they inherit feathered or featherless trunks. As they grow up hybrids become more obvious, however, as they are generally short and thin, and most have very noticeable speech impediments and high, cracking voices. These hybrids are nevertheless also fertile, at least with the woolly parent species.