The collapse of the Follia Plateau

90 million and 96,000 years into the future

More than 5,000 years have passed since Sirocco crossed the Ponti Archipelago, an ice bridge between two worlds. While Sirocco itself is long gone, its legacy endures: over the last millennia, other borax followed its path, establishing a permanent populations in the Ponti Archipelago and then gradually expanding beyond this region, advancing westward towards the Sanctuary Peninsula. Though the pace of their expansion wasn't incredibly fast, these highly versatile marsupials, capable of opportunistically feeding on a wide range of resources, overcame the almost lifeless sea ice environment dividing the two bioregions.

Upon reaching the Sanctuary Peninsula, they discvered plenty of new food sources, both terrestrial and marine. For borax, this is the start of a bonanza: thanks to the abundance of prey and the dispersion of new individuals from east, their population in the Sanctuary Plateau grew from 1 to 1000 in just a century, with tremendous consequences to the ecosystem of the peninsula.
The local "megafauna", lacking effective anti-predator behaviors, was the first to face severe impacts. Tramplerats, vulnerable and bountiful prey for borax, were completely wiped out 500 years after borax's arrival, demonstrating the fragility of this rodent species. Even if each borax consumed just a single tramplerat per month, the high natural mortality and low reproductive rate of tramplerats would still not be sufficient to prevent their extinction.  
The aggressive defense mechanism of trenchcrawlers proved to be equally ineffective against a predator five times the size of the continent’s previous apex carnivore. After enduring for two millennia, even these large birds succumbed to extinction.

The loss of just these two megafauna species triggered tremendous cascading ecological effects. Doorpeas shrubs, previously limited by the trampling actions of tramplerats and trenchcrawlers, began expanding southward and become more common, altering the plateau's grassy landscape. The resulting shrub encroachment decreased the land’s albedo, exposed the soil to deeper degradation because of inconstant plant's roots size, and contributed to the fragmentation and thinning of permafrost layers, with a sharp decline in productivity of the current trample steppe. 

With prey dwindling and competition intensifying, running carnieri disappeared six centuries after borax's arrival. The large vertebrate biomass of the Follia Plateau plummeted from 3 tons to just 300 kilograms per square kilometer in only two millennia. Plague pinpiercers managed to survive but became increasingly scarce in the Sanctuary Plateau. The scarcity of running carnierei and pinpiercers allowed ottofoxes and banchisaraptors, previously suppressed by carnieri and pinpiercers, to flourish at higher denisities in the Follia Plateau. The unchecked proliferation of these mesopredators dealt another blow to the already diminished microvertebrate populations. As resources dwindled and competition intensified, sneaking carnieri vanished, marking the extinction of the carnieri lineage.

The trample steppe, a rich and diverse ecosystem that thrived throughout the Biancocene, has come to an end.
A new epoch now is slowly blooming on this devastated horizon.