Sift through your memories and excavate an image of a fossil. Maybe you’re picturing dinosaur bones, the imprint of an ammonite, or the fronds of a fern etched into stone. But there’s a whole other category of fossilized remains that can tell us about life way before T. rexes, or even twigs, existed on this planet. That’s fossilized evidence of microbes.

Microbiologist Paula Welander uses these ancient remains to understand how life began on Earth. She joined Host Flora Lichtman for our live show at the Fox Theater in Redwood City, California, to talk about how her work may help us find life elsewhere in the universe.

Guest: Dr. Paula Welander is a professor of Earth system science at Stanford University.

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