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Wild mammals have declined by 85% since the rise of humans (ourworldindata.org)
20 points by sohkamyung on April 20, 2021 | hide | past | favorite | 4 comments


This doesn't make sense to me. First, we have this assertion:

> Since the rise of humans, wild land mammal biomass has declined by 85%. Our history with them has been a zero-sum game: we either hunted them or destroyed their habitats with the expansion of agricultural lands.

Then, in the opening paragraphs:

> Travel back 100,000 years and the planet was rich with a wide array of wild mammals. Mammoths roamed across North America; lions across Europe; 200-kilogram wombats in Australasia; and the ground sloth lounged around South America.

> They’re now gone. Since the rise of humans, several hundred of the world’s largest mammals have gone extinct.

What they don't seem to be taking into account is that 100kya, the Earth was on average 3C colder than today. It's accepted that animal body size is strongly correlated by temperature[0]. Therefore, this publication seems to be implicitly asserting that humans are responsible for the end of the last ice age.

That can't be right.

0: https://en.wikipedia.org/wiki/Bergmann%27s_rule


Human invasion of Australia decimated dozens, maybe hundreds of mammal species on that continent to extinction, including the giant Diprotodon. http://www.bbc.com/earth/story/20160208-the-lost-giants-that...


Not unique to humans. When isolated ecosystems get invaded by predatory species the indigenous species get decimated. It could be rats, or cats or humans.

In Africa, where large animals and humans evolved together, the large animals survived up to the advent of modern weapons and a human population explosion brought about by modern agriculture and medicine.


Ditto for the evolution of pathogens, and immune learning.




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