there is, but i don’t think that reason is simply scale. amoebae aren't in danger of extinction or at risk of destabilizing ecosystems. we “save the whales,” but we also “save the bees” (which, for reference, are much smaller than a fetus by the end of the first trimester). while there might be something to this kind of size-based moral intuition, i don’t think it’s enough to “[possibly] explain why secular societies are more permissive of abortion.” still, it’s an interesting argument.