http://www.abc.net.au/science/news/stories/2006/1763328.htm

Earth’s wobble linked to extinctions

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“Palaeontologists have long puzzled over fossil records that, remarkably, suggest mammal species tend to last around two and a half million years before becoming extinct.”

This periodical extinction of mammal species appears to coincide with small shifts in the Earth’s rotational axis and orbit which bring about climate change.

“These were not swift, massive die-outs of the kind that famously wiped out the dinosaurs 65 million years ago, but rather a fade-out of species that could not cope with habitat loss or competition, especially when ice ages kicked in. As they became extinct, other species emerged.”

The effects may not have been global: an Earth wobble that killed in Spain, the location of this study, may have spared life elsewhere.


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