Fossil whale ear bone

Fossil whale ear bones are among some of the most unusual fossils that a collector can find. Whales do not have external-ear structures. Instead, they use the lower jawbone for transmitting sound vibrations to their interiorly located ear structures. They have well developed middle and internal ears and a good sense of hearing.

Their middle ear is enclosed by a bowl-shaped bony structure called the tympanic bulla, which can be fossilized. A fossil bulla is illustrated below.

fossil whale ear bone (bulla), 7 cm wide; Neogene age (Miocene?), California?

Whale ear bones occur in pairs, and the following pictures show replicas of a pair of ear bones from a modern melon-head whale.

models of modern melon-head whale bullae; each one is 3 cm wide

For an interesting article on whale ear bones, including fossil ones, the link is http://vmnhpaleontology.wordpress.com/2007/12/19/in-the-news–whale-ancestors-and-more-ear-bones/

This link provides information on how fossil whale-ear bones help support the evolutionary concept that whales have an ancestry with artiodactyls (modern ones are cows, deer, pigs, etc.).