Mammals were not the first to be warm-blooded - Phys.org

Endothermy, or warm-bloodedness, is the ability of mammals and birds to produce their own body heat and control their body temperature.

Endothermy, or warm-bloodedness, is the ability of mammals and birds to produce their own body heat and control their body temperature. This major difference with the cold-blooded reptiles underpins… [+7209 chars]

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