User blog comment:Lord Loss/Monster Hunter Theory... Blog/@comment-5043481-20121021210526/@comment-4212769-20121023215923

Did I say once that the Gravios didn't make the false decision?

Ukanlos is of course big but not very "compact" unlike the turtle. While it is big it's chest is very slim what doesn't keep well warmth (the plates on its back just let it look much thicker). Also the turtle has fat reserves inside the shell and the shell itself protects it from coldness, too. The leatherback sea turtle can keep the warmth to a temperature of 18° C besides living at the Arctic Circle and not further in but also in tropical and subtropical climates/waters. As it lives in water it doesn't use as much strength as a land living animal. That means Ukanlos has the higher energy loss as well. Ukanlos is also in much colder areas with at least minus temperatures (°C) and couldn't keep the warmth when it wasn't warm-blooded.

This example doesn't apply for Ukanlos, at all.