Isn’t it common for species isolated on an island to become smaller? Compare the so-called “hobbits” (an early human species found on the island of Flores in the East Indies).
I guess.
I read that there were some smaller varieties of Mammoth that lived on a small North American Arctic island as recently as 4,000 years ago. A last remainder of the species that had been likely mostly killed off by meteor strike(s) around 13,000 years ago, with the few remainders killed by hungry human and animal survivors. This remainder no doubt evolved from a few survivors of the meteor by being isolated from large predators and smaller offspring surviving better given the limited food supply. I wonder if polar bears got the last survivors, or if wandering Esquimoes finally killed them.
I think I saw reports that Flores also had small elephants at one time. A lot changed when all that water stored in Ice Age glaciers melted raising world sea levels by 400 feet, and shrinking many land areas. I am glad scientists are finally recognizing that there may be hidden human settlements now lying undiscovered below our current sea levels.