Tooth Loss Precedes the Origin of Baleen in Whales

  title={Tooth Loss Precedes the Origin of Baleen in Whales},
  author={Carlos Mauricio Peredo and Nicholas D. Pyenson and Christopher D. Marshall and Mark D. Uhen},
  journal={Current Biology},
Whales use baleen, a novel integumentary structure, to filter feed; filter feeding itself evolved at least five times in tetrapod history but demonstrably only once in mammals [1]. Living baleen whales (mysticetes) are born without teeth, but paleontological and embryological evidence demonstrate that they evolved from toothed ancestors that lacked baleen entirely [2]. The mechanisms driving the origin of filter feeding in tetrapods remain obscure. Here we report Maiabalaena nesbittae gen. et… Expand
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