A sloth bear (Melursus ursinus), photographed at the National Zoo in Washington DC.
Photo of the Day #903: Sloth bear
A sloth bear (Melursus ursinus), photographed at the National Zoo in Washington DC.
Brian Switek is a freelance science writer and a paleontology volunteer with the Natural History Museum of Utah. He is also author of the books My Beloved Brontosaurus and Written in Stone. ... Read More
Topicsmammals
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An Invasive Disease-Carrying Mosquito Has Spread to the Rocky Mountains
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How to Follow the Trajectory of Comet 3I/Atlas
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The ‘10 Martini’ Proof Connects Quantum Mechanics With Infinitely Intricate Mathematical Structures
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The Hidden Math of Ocean Waves
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