Comments by "Joe R M" (@joermnyc) on "Why some animals are shrinking" video.

@thetimelapseguy8 unfortunate more bears=more competition for food, and more contact with humans as the sea ice comes in later and later for the starving bears. Plus the Grizzly’s range is expanding towards Polar Bears, and some wonder if they will compete with each other, or interbreed to create a Polar-Grizzly hybrid that will drive non-hybrid Polar Bears to extinction.
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The earth had millennia to create and maintain a balance, and in only a few centuries we have disrupted the balance by burning carbon in excess. The only comparison I can think of is a massive volcanic event in what is now Siberia that threw so much ash and gases into the atmosphere that it caused a global temperature drop that wiped out a majority of species in a mass extinction.
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