Caprona

A tropical paradise hidden behind an impenetrable wall of ice in the Arctic, Caprona was so named by the Italian navigator Caproni. What if anything the actual inhabitants of the realm called it is unknown. Caprona was a land where time stood still, and humans coexisted alongside dinosaurs. Like a geologic exhibit, it represented all the ages of the Earth's earliest development. Life in Caprona began in the water, and evolution occurred not just within a single generation but on an individual level. For instance, the most primitive of Caprona's humans, the Bo-Lu, would eventually be called by more advanced tribes such as the Band-Lu and Sto-Lu, to advance up the evolutionary ladder.

Precisely why this is so was never revealed, although Bowen Tyler, shortly before his death, posited that Caprona, the land itself, was alive and had a will of its own.

In the cases of both them and the humans, the further north one journeyed in Caprona, the more advanced they became. The southernmost regions of the island were extremely humid and tropical, and inhabited by marine reptiles, the primitive Bo-Lu, and Jurassic-era dinosaurs such as allosaurs; Cretaceous-era dinosaurs could be encountered further upstream. Its volcanic northernmost regions were colder, had fewer dinosaurs and were home to the Gah-Lu, and lorded over by the (comparatively) advanced, violent Nagas.