In Depth Aetiocetus is an important transitional form as it displays the early origins of the baleen whales, while still retaining teeth that can be identified as incisors, canines and molars like many other mammals. Later descendants would go on to become exclusive filter feeders like many of the modern great whales that swim our … Read more
In Depth Unfortunately still only known from very incomplete remains, Ashorocetus was an early baleen whale. Relatives of Ashorocetus include Aetiocetus and Willungacetus. Further Reading - Classification and distribution of Oligocene Aetiocetidae (Mammalia; Cetacea; Mysticeti) from western North America and Japan - L. G. Barnes, M. Kimura, H. Furusawa & H. Sawamura - 1995.