Life on Earth is amazingly resilient.

Organisms known as extremophiles survive in caves stretching thousands of feet into the Earth's crust,

in deserts that go decades without rain, under high

pressures kilometers deep in the sea, in toxic waste dumps that are entirely unnatural and

inconceivably inhospitable. These tiny extremophilic organisms can live and persist, even thrive,

in environments we would consider dire.

If life lingers on the peripheries of our world, maybe there's a chance that life exists

elsewhere in the universe. I'm Jan 11, and this is the Joy of Why, a podcast from Quantum

Magazine, where I take turns at the mic with my co-host, Steve Strogetz, exploring the biggest questions in math and science today.

In this episode, we talked to astrobiologist and speleologist, that is to say, cave explorer, Penelope Boston, Penny to her friends. We ask her, what can extremophiles

teach us about the fascinating breath and immense diversity of life on Earth? And how can this

knowledge help us recognize life beyond our planet? Penny studies the microbiology of cave

environments to understand the potential for life in the subsurface of other worlds.

She was a professor and co-founder of the Cave and Karst Studies Program at New Mexico Tech,

served as associate director of the National Cave and Karst Research Institute,

and was the former director of the NASA Astrobiology Institute. She is known

for exploring some of the toughest caves in the world. Penny, it's so great to speak with you.

Thanks for joining us. Hi, Jana. It's really a lovely opportunity to get to chat with you about

some of my favorite weird organisms and how they fit into

astrobiology. Yeah, I was very excited about this topic. I remember the first time that I learned

that there were microorganisms in deep hydrothermal vents, essentially metabolizing hydrogen. We often think of life

forms as metabolizing organic material. And so some of these extremophiles are not metabolizing

...