Study on a 400 million year old fish fossil has found a jaw structure that is part of the evolutionary lineage linked to humans. The jaw joint in this ancient fish is still in the human skull, but is now part of the middle ear.

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Study on a 400 million year old fish fossil has found a jaw structure that is part of the evolutionary lineage linked to humans. The jaw joint in this ancient fish is still in the human skull, but is now part of the middle ear.