The Archeacene is the first geological era on Loki where terrestrial life is present and abundant, beginning approximately 500,000 years after humans seeded the planet (deliberately or otherwise) with organisms from their home world. It is marked by the evolution of the first genetically distinctive species from their ancestral stock. As such, species diversity is still relatively low (at least compared to Earth), but the foundations have been established for flourishing and diverse ecosystems in the future.
Climate
During the Archeacene Loki is an icehouse climate, albeit with average temperatures higher than that of Earth. Ice sheets form at the poles during winter but melt away in the summer. Permanent ice is rare and restricted to high mountain peaks and sheltered, elevated valleys. Continuing the trend started with the establishment of grasses the climate is cooling, though this is plateauing out as the ecosystem stabilises.
The frozen ocean in winter forms a solid ice sheet, linking together scattered islands and forming a bridge between continents.
Geography
Loki features three major continents- Whiskiia, Brandiia, and the colloquially named Bugaria.
Whiskiia
Whiskiia is an elongated continent that stretches across both hemispheres. It is divided into two regions: Northern and Southern.
Southern Whiskiia was where the crash that bought the rats to Loki occurred, making it essentially the cradle of ratkind. The geography of Southern Whiskiia is predominantly rolling grasslands, rising to hills in its northern reaches. Cooled by ocean winds, the coasts enjoy pleasantly warm temperatures, with the interior reaching tropical levels.
Northern Whiskiia has more varied terrain than the southern half, with flat plains to the west and mountainous regions to the east. The western coastline is particularly picturesque, ranging from rugged cliffs to sheltered bays and calm lagoons. The mountain chains and higher latitude make Northern Whiskiia noticeably colder than its southern neighbour.
Brandiia
Brandiia is mostly located within the northern hemisphere, though its southern area reaches across the equator. It too is divided into two regions, Northern and Southern.
Northern Brandiia is notable for its hilly interior; its northern reaches feature more uniform elevations due to erosion from the constant freeze-thaw of the icecaps. The more level terrain around its coasts has led to a myriad of river systems and fragmentated grasslands.
Southern Brandiia is unusually flat, with little variance in topology. As a result the terrain is a mostly wide open plain, with warm desert conditions towards the equatorial centre. Due to continental drift Southern Brandiia is slowly pulling apart from its neighbour and migrating further southwards, creating a series of rifts and inlets in the connecting land between them.
Whiskiia and Brandiia are loosely connected by a series of small islands close to the poles. These islands are generally frozen over in the winter, with ice bridges forming between them. Although this allows terrestrial animals to migrate between the continents the unfavourable terrain and conditions limits this passage.
Bugaria
Bugaria is a large landmass lying to the east of Whiskiia in the northern hemisphere. Fairly uniform in shape, Bugaria features a cluster of elevated terrain in its centre; the remnants of the volcanic period that created the landmass. Although seeded with grasses and invertebrates, Bugaria remains uncolonised by rats due to its distance from the other continents. Instead, its fauna consists entirely of invertebrates such as nematodes and beetles. Geologically stable and largely unmoving due to its positioning in the centre of rotating plate, Bugaria remains isolated from the rest of the world.