Most of the introduced animals had few difficulties adjusting to this world. Rabbits and mice had plenty of food, and while sparrows had some difficulty raising their young on a low invertebrate biodiversity they eventually adjusted and spread far and wide, exceeding the distribution of the mammals and reaching islands off the coast of the "Catland" mainland in all directions. Cats were restricted to wherever there was prey, and the pre-existing temperate-dwelling viviparous lizards were restricted to cooler areas in range, thus in most of Catland they were not present. It was when the mice, rabbits and sparrows spread out beyond the seeding zone that the cats were able to migrate into new lands also.

The breakaway population of humans that tried to terraform this world used climate engineering technology that would have a lasting effect without intervention. However long, this effect was still limited and would fade away over the next 100,000 years. By the time the climate engineering effects had worn off from the planet, the temperature had reached a new equilibrium at 6 degrees higher than before. It was a huge delay in the diversification of the few species this planet had, and where many members of families or genera had once been present their number of species had been narrowed to just one or a few.

Due to this permanent global temperature rise biomes shifted polewards, with tundra biomes being eliminated with just a few tundra species of mosses, grasses and some cold-adapted elderberry in highest mountains at or near polar latitudes. A scorched dead zone with practically no life opened up at the equator replacing the band of rubber tree rainforest that the first humans had helped cultivate. Rubber tree almost became extinct, surviving in scraggly dwarfed, stressed forms in the cooler wetter mountains along with a few other rainforest trees that hung on alongside them.

The cats that survived this biome shift were limited to the very South of Catland, in the more fertile temperate elderberry and mulberry forests, subtropical woodland which additionally contain date palms, and open grasslands of new wild species of once commercial grains like millet, wheat and maize, as well as originally wild grass such as digitgrass. Anywhere else on the continent is usually too hot for cats to inhabit year-round or too dry for the flora and macrofauna needed to support healthy populations of their prey.