Research NewsPaleontology

Why Mammal Ears Went on the Move

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Science  01 Dec 1995:
Vol. 270, Issue 5241, pp. 1436
DOI: 10.1126/science.270.5241.1436


The mark of a mammal is a migrating ear. A chain of small bones that used to be part of the jaw moved back to the skull and became the middle ear—a journey that set true mammals apart from every other vertebrate. A new theory argues that this mysterious transformation of jaw and ear was actually driven by a different body part: the expansion of the brain.