Dozens of animals, some on land but many in the ocean, can produce light within their bodies through chemical reactions. Scientists are still trying to understand when and why this trait developed.
Humans aren’t the only animals that have names for each other − and studying animals that use names can teach researchers more about how human names evolved.
Male proboscis monkeys are known for their large, bulbous nose appendages. It’s a strange feature to evolve – with new research shedding light on their unlikely origin story.
You can see this dog’s third eyelid in the corner of its eye.
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Symbiosis is so much part of life on Earth that it has shaped the evolution and structure of cells. It’s happening almost everywhere we look, including inside our gut.
Cicadas climb up a tree at the U.S. Capitol in Washington, D.C., during the Brood X emergence in 2021.
Bill Clark/CQ-Roll Call, Inc via Getty Images
Horse fossils are abundant and widespread across North America. Scientists often use their long history to illustrate how species evolve in response to a changing environment.