STEVE INSKEEP, HOST:
Researchers are studying a period of climate change. They've gone back into the past to find out how much an earlier period of change affected the species on this planet. It's known that this earlier era led to mass extinctions in places like Europe, but the results in other parts of the world have been less understood until now.
ERIK SEIFFERT: There's always been a question of what happened in Africa in the transition from the Eocene to the Oligocene around 34 million years ago.
SCOTT DETROW, HOST:
That's professor Erik Seiffert of the University of Southern California. He and a number of other researchers shared their findings this month, but Africa and the Arabian Peninsula did not avoid climate change. In fact, those regions lost an estimated 63% of mammal species due to a cooling climate.
INSKEEP: Seiffert says the fossil record from Africa during this period is sparse, which makes this sort of research hard. So his team tried a new approach.
SEIFFERT: We only looked at five different groups - two groups of primates, two groups of rodents and a group known as hyena dogs.
INSKEEP: And within that limited number of species, they put together family trees for how groups of mammals evolved through time.
SEIFFERT: Instead of them being, you know, you and your parents and your grandparents, they are species going back millions and millions of years.
INSKEEP: Take that, ancestry.com.
DETROW: So the team used that approach to try to figure out just how many other species in the region went through the same catastrophic events.
DORIEN DE VRIES: That extinction event is a reset button.
DETROW: Dorien de Vries is a paleontologist and co-author of the report.
DE VRIES: A lot of these families that we saw before go extinct, small subsample survives, and that's the start of the anthropoid family or the hominids, the apes, as we see it today.
INSKEEP: Bottom line here - Seiffert says humans dodged a bullet.
SEIFFERT: At that time, it appears that several other primate lineages were going extinct, so we were - yeah, we were one of the only lineages that made it through.
INSKEEP: Hopefully, we'll make it through next time.
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