MARY LOUISE KELLY, HOST:
The image of a penguin might bring to mind an endless march across windswept ice. The reality of penguins is a bit different, says Grant Ballard of Point Blue Conservation Science.
GRANT BALLARD: There's actually only two species of penguin that really love ice.
LEILA FADEL, HOST:
Only two species. Many others live in warmer waters.
BALLARD: So an emperor penguin could conceivably be dealing with something like minus 70 degrees or even colder than that, especially with wind chill. But a Galapagos penguin is encountering temperatures that are around 100 degrees Fahrenheit.
KELLY: So how did penguins evolve with such different lifestyles? A new study in the Proceedings of the National Academy of Sciences has some answers.
RAURIE BOWIE: We've been able to resolve several long-standing questions about penguin evolution, in particular where penguins originated.
FADEL: Rauri Bowie of UC Berkeley is an author on that study. He says there's been a long debate about where the first penguins evolved. Was it Antarctica or farther north in New Zealand, as others have suggested?
KELLY: Well, armed with genetic evidence from 18 species of modern-day penguins, his team has an answer.
BOWIE: Which turned out to be along the coast of Australia and New Zealand and nearby islands of the South Pacific.
KELLY: They say that happened around 22 million years ago.
FADEL: From there, the penguins surfed on a circular current at the bottom of the world.
JULIANA VIANNA: There is a clockwise current, and so they use this current to colonize, like, Antarctica region.
FADEL: Juliana Vianna of the Catholic University of Chile is a co-author. She says 11 million years ago, that current revved up, and penguins used it to slingshot themselves throughout the Southern Hemisphere.
KELLY: That's right - slingshot. The researchers also observed genetic adaptations some penguins picked up along the way, like the ability to drink seawater, also changes in how some species use oxygen, allowing them to dive deep.
FADEL: But that doesn't mean penguins will be quick to adapt to modern-day climate change. Here's Bowie again.
BOWIE: This adaptation to being able to occur in freezing cold waters and tropical waters occurred over a period of 20 million years. And this doesn't mean that penguins are going to be able to keep up with the ocean's warming today.
KELLY: If there is one thing the paper makes clear, it's that the evolution of penguins is far from black and white.
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