3 ms·

Maybe, although a more correct term is insular dwarfism, whereby populations are supposedly subject if they’re isolated in anyway. Definitely not my area of ex

• im3w1l 1y ago
  Not super knowledgeable either, but I'm thinking that it's simply because it's fairly easy for animals to change size. Like imagine a size constant in your code and you can just update it and everything magically works. So when you have two populations that get cut off with slighly different environments and selection pressures their sizes are likely to diverge.
  • thaumasiotes 1y ago
    > I'm thinking that it's simply because it's fairly easy for animals to change size. Like imagine a size constant in your code and you can just update it and everything magically works. No, the opposite is the case. You can just scale an animal up. But it won't work well; the larger size requires different support structures than the normal size does. Hence, giant humans tend to be in poor health, with circulatory and other problems. The reason island populations show size changes is that the tiny environment leaves environmental niches open, and animals of the wrong size can radiate into those empty niches without facing competition from animals that are already filling them more effectively. Island dwarfism is common, and so is island gigantism. Note that New Zealand obviously is small enough for island dwarfism, since it was small enough for island gigantism. The size seems less relevant than the fact that it was isolated by deep ocean.