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I've looked into this, and there's no great way to do so, becuase the concept of species really just means large morphological changes. We assume everything is
by solinent 7y ago
I've looked into this, and there's no great way to do so, becuase the concept of species really just means large morphological changes. We assume everything is taxonomized (a tree), but in reality there is no tree--sometimes there is cross polination after some time apart. Ultimately they have a precise set of morphological criteria for each species, and they arrive at this criteria based on a sampling of animals and associating their morphology with their DNA.
They also use string similarity algorithms to determine morphological order, so we don't strictly know the order at the most precise level.
Of course, this is all very controversial, some people think we're always changing gradually and some people think we always change rapidly. I think they're both wrong--sometimes organisms change rapidly, and sometimes they change rapidly, depending on environmental factors.
disclaimer: I'm no expert, I've just looked at it from an algorithmic view and read some taxonomical texts as I had the same question as you.
- moultano 7y agoThe further you zoom out, the more tree-like it gets, but if you zoom in on any particular node in the tree, like hominids, then it becomes a tangled mess.
- mirimir 7y agoExactly. It's my vague impression that you get species that can't interbreed after extended geographic/habitat isolation. But short of that, it's a tangled mess, with complex fertility patterns.
- solinent 7y agoI remember learning this vaguely as well, it's just a relatively useful rule with lots of exceptions, but it is not a law--it happens even after extended isolation: https://en.wikipedia.org/wiki/Hybrid_(biology) https://en.wikipedia.org/wiki/Hybrid_(biology) https://en.wikipedia.org/wiki/Interbreeding_between_archaic_and_modern_humans https://en.wikipedia.org/wiki/Interbreeding_between_archaic_... Some examples of hybrids without human influence (well that's arguable): https://en.wikipedia.org/wiki/Lonicera_fly https://en.wikipedia.org/wiki/Lonicera_fly https://en.wikipedia.org/wiki/Red_wolf https://en.wikipedia.org/wiki/Red_wolf The grand daddy of "hybrids" (twelve species): https://en.wikipedia.org/wiki/Celosia_argentea https://en.wikipedia.org/wiki/Celosia_argentea from here: https://en.wikipedia.org/wiki/Hybrid_(biology)#Speciation https://en.wikipedia.org/wiki/Hybrid_(biology)#Speciation Also you can go beyond hybrids: https://en.wikipedia.org/wiki/Polyploidy#Types https://en.wikipedia.org/wiki/Polyploidy#Types As an amateur I'd hypothesize if the species diverges and then relocates, but is subject to similar environmental pressure, the morphological changes won't be great enough to prevent the organisms from interfacing and then reproducing. We've determined this through string similarity algorithms, so really I'd say we can't be completely certain here either.
- mirimir 7y agoThanks! Lots of great links there.