Australia is known for its unusual animal life, from koalas to kangaroos. But once upon a time, the Australian landscape had even weirder fauna, like Palorchestes azael, a marsupial with immense claws and a small trunk. There was Protemnodon mamkurra, a massive, slow-moving, kangaroo-like creature. And Zygomaturus trilobus, a wombat the size of a hippo. They’re all extinct now, and researchers are trying to figure out why. Host Flora Lichtman talks with researcher Carli Peters about ZooMS, a technique that allows researchers to use collagen from ancient bone fragments to identify species, offering clues to those ancient extinction events. Peters recently described using the technique in the journal Frontiers in Mammal Science.

And, a recent study in the journal Nature Astronomy hints that our own Milky Way galaxy may not be doomed to collide with Andromeda after all. Till Sawala, an astrophysicist at the University of Helsinki, joins Flora to talk about the finding.

Guests: 
Dr. Carli Peters is a postdoctoral researcher at the Interdisciplinary Center for Archaeology and the Evolution of Human Behavior at the University of Algarve in Faro, Portugal.
Dr. Till Sawala is an astrophysicist at the University of Helsinki.

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