5 ms·

> no actually, some recent good news about a remote polar bear population came through Source? Even with short term fluctuations, when the sea ice is gone, pol

> no actually, some recent good news about a remote polar bear population came through Source? Even with short term fluctuations, when the sea ice is gone, polar bears are fucked.

steve_adams_86 3y ago
I might be mistaken, but they could be referring to polar bears seen surviving for a long time without much sea ice, further south than usual in Greenland. The thing worth noting here is that this means we’re seeing polar bears as we commonly recognize them still going extinct. What will survive will be an offshoot of them which survives by different means in different environments. So I’m not sure it’s actually good news about polar bears more generally.
- swalling 3y ago
  I think if humans give up on the mistaken idea of species as a fixed concept rather than an evolutionary line, then it's fine. What matters is that a healthy ecology which supports the largest land predator on Earth persists. The thing we're trying to avoid is a repeat of the Permian–Triassic extinction event, where afterwards Lystrosaurus composed 95% of land vertebrates for millions of years. Domesticated animals already compose a massive proportion of the bird and mammal biomass.
- ianburrell 3y ago
  Polar bears without ice and snow will become brown bears. Polar and brown bears can cross breed. My guess is that the polar bears will merge and turn back into brown bears. But polar bears will be gone.
  - steve_adams_86 3y ago
    This was my intuition as well. The several-hundred year old populations haven’t become brown bears yet (not sure if they’re present in that eco system), but it seems likely that this would be inevitable on a long enough time scale. Having said that, I should also point out that I don’t know anything about any of this.
    - swalling 3y ago
      The barrier to this is dietary diversity. Brown bears are among the most omnivorous large mammals, whereas polar bears only eat plant matter in limited amounts / specific locales. A brown bear will get fat on food a polar bear starves on. You can’t reproduce if you’re not well fed.

> no actually, some recent good news about a remote polar bear population came through Source? Even with short term fluctuations, when the sea ice is gone, polar bears are fucked.

steve_adams_86 3y ago

I might be mistaken, but they could be referring to polar bears seen surviving for a long time without much sea ice, further south than usual in Greenland. The thing worth noting here is that this means we’re seeing polar bears as we commonly recognize them still going extinct. What will survive will be an offshoot of them which survives by different means in different environments. So I’m not sure it’s actually good news about polar bears more generally.

swalling 3y ago
I think if humans give up on the mistaken idea of species as a fixed concept rather than an evolutionary line, then it's fine. What matters is that a healthy ecology which supports the largest land predator on Earth persists. The thing we're trying to avoid is a repeat of the Permian–Triassic extinction event, where afterwards Lystrosaurus composed 95% of land vertebrates for millions of years. Domesticated animals already compose a massive proportion of the bird and mammal biomass.
ianburrell 3y ago
Polar bears without ice and snow will become brown bears. Polar and brown bears can cross breed. My guess is that the polar bears will merge and turn back into brown bears. But polar bears will be gone.
- steve_adams_86 3y ago
  This was my intuition as well. The several-hundred year old populations haven’t become brown bears yet (not sure if they’re present in that eco system), but it seems likely that this would be inevitable on a long enough time scale. Having said that, I should also point out that I don’t know anything about any of this.
  - swalling 3y ago
    The barrier to this is dietary diversity. Brown bears are among the most omnivorous large mammals, whereas polar bears only eat plant matter in limited amounts / specific locales. A brown bear will get fat on food a polar bear starves on. You can’t reproduce if you’re not well fed.