alt Hacker News> Two bird populations living in the same locale but divided by a mountain range therefore not naturally breeding with each other would classify as a different species, even if they could breed with each other.
Really? I thought the requirements for species classification were: (1) must be able to reproduce and (2) offspring must be fertile.
Is it less objective than that?
Replies
Archelaos • today at 4:59 AM
Polar bears can have furtile offspring with grizzly/brown bears. See: https://en.wikipedia.org/wiki/Grizzly%E2%80%93polar_bear_hyb...
whycombinetor • today at 5:20 AM
Interfertility is not an equivalence relation, does not form equivalence classes https://en.wikipedia.org/wiki/Ring_species
There are a lot of subtleties. Ring species are a particularly fun one: you can have a population that live around some natural obstacle (like a large body of water) where individuals can breed successfully with individuals near to them but not with ones further way (like directly across the barrier), in a continuum of variation.