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Mammal

The mammals are the class of vertebrate animals characterized by the production of milk in females for the nourishment of young, from mammary glands present on most species and specialized skin glands in monotremes that seep or ooze milk; the presence of hair or fur; specialized teeth; three minute bones within the ear; the presence of a neocortex region in the brain; and endothermic or "warm-blooded" bodies. The brain regulates endothermic and circulatory systems, including a four-chambered heart. Mammals encompass some 5,500 species (including humans), distributed in about 1,200 genera, 152 families and up to 46 orders, though this varies with the classification scheme. Most mammals give birth to live young, but a few (the monotremes) lay eggs. Live birth also occurs in some non-mammalian species, such as guppies and hammerhead sharks; thus it is not a distinguishing characteristic of mammals.

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April 28, 2026

A new study suggests Neanderthals didn’t go extinct simply because of climate change or competition with Homo sapiens. Instead, the key difference may have been social connectivity—Homo sapiens formed stronger, more flexible networks that helped ...
A mysterious “golden orb” found more than two miles deep in the Gulf of Alaska left scientists baffled for over two years, sparking wild speculation about its origins. After an intensive ...
Dinosaur DNA may still be out of reach, but scientists are uncovering something almost as exciting—ancient blood vessels hidden inside fossilized bones. In a massive Tyrannosaurus rex nicknamed Scotty, researchers discovered a network of preserved ...
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The golden oyster mushroom may be a culinary hit, but it’s becoming an ecological problem. Scientists warn it’s spreading quickly through U.S. forests, where it outcompetes native fungi and reduces biodiversity. In just a decade, it has appeared ...
Beneath the dry farmland of New South Wales lies a hidden window into a lost rainforest teeming with life from 11-16 million years ago. At McGraths Flat, scientists have uncovered fossils preserved in astonishing detail—not in typical rock like ...
A vivid green pitviper hiding in Sichuan’s misty mountains has been revealed as a completely new species. Scientists had overlooked it for decades, assuming it was a common snake—until DNA analysis proved otherwise. Named after Laozi, it ...
Scientists have uncovered a fascinating new species of pit viper in Myanmar that seems to blur the very definition of what a species is. This snake, now named the Ayeyarwady pit viper, puzzled ...
Scientists at UC Riverside have found a clever new way to outsmart termites—by turning their own instincts against them. Using a natural pine scent called pinene, which smells like food to termites, researchers can lure the pests straight toward a ...
Scientists have discovered that moringa seeds can help pull microplastics out of water, rivaling standard chemical treatments. The plant-based extract causes plastic particles to clump together, making them easier to filter away. In some conditions, ...
Scientists have discovered that methane in the open ocean is produced by microbes under nutrient-poor conditions, solving a long-standing mystery. As warming oceans reduce nutrient mixing, these ...

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