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It was rainforests, not humans, that killed off SE Asia's megafauna

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https://theconversation.com/it-was-growi...una-147656

EXCERPTS: Southeast Asia has lost many large mammal species over the Quaternary period, the past 2.6 million years. They included the world’s largest ever ape, Gigantopithecus, elephant-like creatures known as stegodons and large water buffaloes. These extinctions also include one of our closest relatives, Homo erectus, and two island offshoots of the human family tree – Homo floresiensis (the “Hobbit”) and Homo luzonensis. One final human species is also recorded in the genes of Southeast Asians today: the Denisovans, who were once likely widespread throughout the region.

According to previous research, the lead antagonist in the megafauna extinction story is humans. [...] r research, we examined environmental changes in Southeast Asia over the past 2.6 million years, to determine how they may have impacted extinctions.

[...] the first 1.5 million years or so of the Pleistocene (the geological epoch that lasted from about 2,580,000 to 11,700 years ago), the northern parts of Southeast Asia were largely forest, while the southern parts were woodlands or grasslands.

Later, from about one million years ago, forests retreated everywhere in the region and grasslands dominated. Coincident with these changes, large forest-adapted animals including Gigantopithecus and a giant panda relative disappeared from Southeast Asia’s northern parts.

[...] Later still, around 400,000 years ago ... forest conditions returned. At the same time, grassland-adapted creatures that had filled the region, including giant hyenas, stegodons, bovids and Homo erectus began to disappear - and largely went extinct by the end of the Pleistocene. ... By the last few tens of thousands of years, we see the first evidence of stratified, closed-canopy rainforests in Southeast Asia. These have dominated the region for the past 20,000 years or so.

Rainforest-adapted species should have been advantaged by the return of the rainforests, but one interloper changed that. Homo sapiens appears to be the only species in our family tree that was able to successfully adapt to and exploit rainforest environments. [...] Megafauna grassland specialists were the greatest loss as a result of disappearing savannahs 400,000 years ago. Today, rainforest megafauna are also at great risk of extinction... (MORE - details)
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