Researchers have identified a 33-million-year-old whale fossil that may represent the missing link between toothed and baleen whales, according to a study published today (November 29) in Current Biology. They call the fossilized species Maiabalaena nesbittae.
The whale’s fossilized jaw has neither teeth nor evidence of baleen, and its age places it between the emergence of the first whales, which had teeth, and the evolution of the keratin-base sieve that baleen whales use to filter their food. Baleen whales likely arose after their ancestors passed through a toothless intermediate stage, the researchers believe.
“When we talk about whale evolution, text books tend to focus on the early stages, when whales went from land to sea,” Nicholas Pyenson, the curator of fossil marine mammals at the Smithsonian’s National Museum of Natural History, in Washington, DC, says in a press release. “Maiabalaena shows that the second phase of whale evolution is just ...
