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A post-reproductive toothed whale mother and her son. David Ellifrit/Center for Whale Research hide caption

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David Ellifrit/Center for Whale Research

Most animals don't go through menopause. So why do these whales?

Across the animal kingdom, menopause is something of an evolutionary blip. We humans are one of the few animals to experience it. But Sam Ellis, a researcher in animal behavior, argues that this isn't so surprising. "The best way to propagate your genes is to get as many offspring as possible into the next generation," says Ellis. "The best way to do that is almost always to reproduce your whole life."

Most animals don't go through menopause. So why do these whales?

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A female cockroach considers accepting a sugary offering from a male cockroach. Ayako Wada-Katsumata hide caption

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Ayako Wada-Katsumata

These cockroaches tweaked their mating rituals after adapting to pest control

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A new study finds that orca mothers still feed their adult sons. It's a bond that may come with costs, researchers say. David K. Ellifrit/Center for Whale Research / NMFS research permit #21238 hide caption

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David K. Ellifrit/Center for Whale Research / NMFS research permit #21238

Killer whale moms are still supporting their adult sons — and it's costing them

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A glass is filled in with water on April 27, 2014 in Paris. Scientists studying what makes us thirsty have found the body checks in on our water consumption in several different ways. FRANCK FIFE/AFP via Getty Images hide caption

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FRANCK FIFE/AFP via Getty Images

Thirsty? Here's how your brain answers that question

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"Better Together" will illustrate a story about bird personalities and cooperation when the book Great Adaptations is published in the fall. James Munro/Courtesy of Breadpig, Inc. hide caption

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James Munro/Courtesy of Breadpig, Inc.

A man reaches for a wooden cross in the sea during an Epiphany ceremony in the Greek port of Thessaloniki on January 6, 2011. Sakis Mitrolidis/AFP/Getty Images hide caption

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Sakis Mitrolidis/AFP/Getty Images