TINY TEETH OF AN EXTINCT LATE CRETACEOUS MAMMAL

Multituberculates represent an extinct order of rodent-like mammals (mouse-sized to beaver size) that lived from the Middle Jurassic to late Eocene time. They had their evolutionary peak during Late Cretaceous and Paleocene time. There are about 200 known species (Wikipedia, 2024).

Typical early multituberculate animal (rat-size). Image modified (by the author) from a figure in Savage and Long (1986).

Typical skull of an early multituberculate.

Two views (left side = first image) and (right side = second image) of the same tooth (4 mm wide, 3 mm tall, and 1 mm in thickness) of the multituberculate Mesechua? from the Upper Cretaceous Bug Creek “anthills” locality in Montana. This tooth is a lower jawbone (mandible) premolar cheek tooth cheek anterior to larger molars.

Multituberculates are important fossils because they are found to have flourished on “both sides of the” famous K/T boundary [aka Cretaceous/Tertiary boundary]. These fossils help prove that small mammals did not go extinct at the end of the Cretaceous; instead, they survived and flourished for millions of years to come.

Note: This blog benefited greatly from a single multituberculate tooth (see figure above). Such specimens are very rare for most fossil collectors. This tooth was kindly given to me by the late Father Jenkins who taught biology at Loyola Marymount College for many years. He was very interested in fossils, especially trilobites and early mammals. 

References Consulted:

Savage, R.J.G. and M.R. Long. 1986. Mammal evolution an illustrated guide. British Museum (Natural History). 259 pp.

Wikipedia, 2024. Multituberculates.

note: A post in the blog of The Fossil Forum.com was very useful in helping me in the generalized identification of the multituberculate tooth used in this blog.