Scientists have identified when mammals became warm blooded about 233 million years ago, far later than once believed. By analyzing the inner ear canals of more than 300 living and extinct species, researchers found that the narrow structures linked to warm bloodedness emerged long after early cynodonts, reshaping our understanding of mammalian evolution.

How do echidnas survive Australia's heat without sweating or panting? Thermal imaging reveals their secret cooling tricks, including nose bubbles that work like natural misters.