5 ms·

It's not just a rooted tree, it has crossovers and cycles. Trying to draw boundary boxes is a fools hardy.

by goldenkey 5y ago

jameshart 5y ago
This is true, when you zoom in closely, but when you zoom out, it is quite treelike. phylogeny isn't useless just because the process of speciation isn't instantaneous.
- User23 5y ago
  It’s very helpful to learn to recognize lumper versus splitter arguments. Pointing out that lumping things together or splitting things apart is arbitrary just isn’t very interesting. What is interesting is why some things are lumped and some are split. For example why are polar bears and grizzly bears considered different species? They can breed just fine after all.
  - jameshart 5y ago
    Right, and when you notice that a bunch of organisms share a trait, the fact that they share that trait in spite of their common ancestor not sharing it is inherently interesting, right? We know that traits are heritable, so when you have a bunch of different organisms that exhibit the same characteristic, if you can trace back and determine they are all specialized descendants of some ancestor which first developed that characteristic, that’s the complete story right there. But when we see the same behavior appear in different organisms without them sharing a common root for that characteristic that’s interesting precisely because we need another means to explain it. I mean, if grizzlies and polar bears could interbreed even though their nearest common ancestor was, say, some kind of small Cretaceous rodent, then weld have some explaining to do, right?
    - User23 5y ago
      Absolutely. I find the cladistics approach appealing. On a bit of a tangent I did some searching and found this[1]. Nightjars are cool! [1] https://scienceblogs.com/gregladen/2010/09/09/one-could-say-that-bats-evolve https://scienceblogs.com/gregladen/2010/09/09/one-could-say-...

5 ms·

It's not just a rooted tree, it has crossovers and cycles. Trying to draw boundary boxes is a fools hardy.

by goldenkey 5y ago

It's not just a rooted tree, it has crossovers and cycles. Trying to draw boundary boxes is a fools hardy.

jameshart 5y ago
This is true, when you zoom in closely, but when you zoom out, it is quite treelike. phylogeny isn't useless just because the process of speciation isn't instantaneous.
- User23 5y ago
  It’s very helpful to learn to recognize lumper versus splitter arguments. Pointing out that lumping things together or splitting things apart is arbitrary just isn’t very interesting. What is interesting is why some things are lumped and some are split. For example why are polar bears and grizzly bears considered different species? They can breed just fine after all.
  - jameshart 5y ago
    Right, and when you notice that a bunch of organisms share a trait, the fact that they share that trait in spite of their common ancestor not sharing it is inherently interesting, right? We know that traits are heritable, so when you have a bunch of different organisms that exhibit the same characteristic, if you can trace back and determine they are all specialized descendants of some ancestor which first developed that characteristic, that’s the complete story right there. But when we see the same behavior appear in different organisms without them sharing a common root for that characteristic that’s interesting precisely because we need another means to explain it. I mean, if grizzlies and polar bears could interbreed even though their nearest common ancestor was, say, some kind of small Cretaceous rodent, then weld have some explaining to do, right?
    - User23 5y ago
      Absolutely. I find the cladistics approach appealing. On a bit of a tangent I did some searching and found this[1]. Nightjars are cool! [1] https://scienceblogs.com/gregladen/2010/09/09/one-could-say-that-bats-evolve https://scienceblogs.com/gregladen/2010/09/09/one-could-say-...