Life and Environment of Borea

150 Million Years PE

Borea, Serina's northernmost landmass, was locked in glaciation for the entirety of the Cryocene. Though at the time of Serina's colonization it supported the same lush grasslands and surely a wide variety of endemic bird and insect life, by fifty million years PE any rich ecology it had once supported had been wiped out by the advancing polar ice cap. When the continent began to thaw following the increase in global temperatures that kickstarted the Thermocene era, this highly isolated landmass was gradually recolonized by travelers from afar.

It's now been 100 million years since Borea began to warm, and Borea now predominately supports a mild temperate climate, though its northern coastlines could be considered boreal and one of only a few areas to experience significant seasonal snowfall in winter. The south of the west island and the northwest of the east island are relatively dry and made up predominately of grassland, while the east of both islands and the northern coast of the west island are relatively wet, supporting dense stands of forest. After many millions of years locked in ice, by the late Thermocene this small polar continent is again home to a wide variety of strange wildlife which can be found nowhere else on Serina. Since the rise of global sea levels at the start of this epoch, the continent has been divided into an east and a west island, along with a handful of smaller offshore isles, with the native flora and fauna varying in their range; some animals are endemic to one or the other, while certain others are present upon several or even all of the islands in the archipelago.

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All land animals on Borea in the late Thermocene are descended from either flying birds which reached the island after it thawed, or from aquatic birds which were able to reach it by water - no relics survive from the eons before it was locked in ice. The great majority of this second wave of colonists would thus not have been primitive seed-eating canaries but specialized carnivorous seabirds which utilized the islands only to breed but remained tied to the sea, among them flightless penguin-like species and soaring gull-like forms, as well as marine birds such porporants which moved into Borea's many rivers and lakes, previously carved by the advance and retreat of glaciers, giving rise to several endemic freshwater species.

As soon as grasses and trees colonized the islands, however, their seeds carried on the wind or by the waves, an environment was developed that would be conducive to the survival of herbivores and the beginning of a true land-based ecosystem. Soon a group of small rail-like birds would colonize the island from the south; it would be these small omnivores which evolved over the following millennia into the continent's major terrestrial herbivores. Predatory falconaries, blown off course during migrations between southern lands, also eventually reached Borea. One lineage began hunting the first small canary-rails on the ground, developing longer legs and subsequently losing its powers of flight entirely and evolving into a group of large cursorial predators known as falcurs; today, they are Borea's apex predators. Faced with such enemies, the small rail-canaries became larger and themselves more adapted to running, evolving into a variety of large and ratite-like grazers and browsers.

The forests on Borea are predominately composed of sunflower trees and single-trunked type-C bamboos which resemble conifers in their growth habit, both evolved from trees of species which produce mobile seeds equipped with fan-shaped structures to disperse on the wind, occasionally reaching the isolated island continent which was now warm enough for their survival. Bangroove forests also grow along the southern coasts, their large and buoyant seeds originally being carried from the south by currents. Notably, there is no ant symbiosis on Borea; though some Borean trees appear to have evolved from myrmecophytes, the specific ant species which they evolved in tandem with did not make the journey along with their airborne seeds. Nevertheless, other groups of ants did reach the island including flying pollinators and more typical burrowing colonial species, as well as representatives from most other groups with flying forms. Once forests had developed upon Borea a number of smaller seed- and insect-eating birds were able to colonize as well and today Borea is home to a rich tapestry of endemic bird species. Notably absent, however, are large megafaunal groups present elsewhere - there are no tyrant serins, serestriders, or serilopes on Borea - there is simply no way that these animals could have crossed the great distance of ocean separating Borea from any other landmass.

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above: along the shores of of a calm bay on the southern coast of Borea's east island, a large predatory porporant has died and been washed ashore during a powerful storm the night before. It isn't long before this windfall of protein begins to attract attention, as an opportunistic falcur follows its nose down to the beach from its more usual haunts in the thickets further upland. Climbing onto the body with the strong grasping talons it retains from its flying ancestors and breaking open the carcass with its sharply hooked bill, it opens up the porporant to a growing variety of smaller sea birds eager for their turn to feed as soon as the falcur has filled its stomach. In the distance, oblivious to the drama unfolding down the beach, a tall browser which looks superficially much like a crane combined with an Earth elephant bird plucks leaves from the canopy of a sunflower tree. It feeds with a long and pointed bill that, even though now used to pluck foliage, portrays its ancestry as a small probing plover-like creature which fed mostly on insects