Baleen whale

Jan. 12, 2024

Roughly 19 million years old fossil jaw bone of a baleen whale estimated to be around nine metres in length found recently.

About Baleen whales:

  • These are any cetacean possessing unique epidermal modifications of the mouth called baleen, which is used to filter food from water.
  • Most mammals have teeth in their mouth. Baleen whales are a strange exception.
  • Baleen is a large rack of fine, hair-like keratin used to filter out small krill from the water.
  • This structure enabled baleen whales to feed efficiently on enormous shoals of tiny zooplankton in productive parts of the ocean, which facilitated the evolution of larger and larger body sizes.
  • Baleen whales are generally larger than toothed whales except for the sperm whale which is very big and has teeth.
  • Many baleen whales migrate annually, travelling long distances between cold water feeding areas and warm water breeding areas.
  • The large whale fossils from Australasia and South America seem to suggest that for most of the evolutionary history of baleen whales, whenever a large baleen whale shows up in the fossil record, it is in the Southern Hemisphere.
  • Baleen whales are ecosystem engineers, their huge bodies consuming tremendous amounts of energy.
  • Upon death, these whales provide an abundance of nutrients to deep-sea ecosystems.