homodontines

Homodontines is a term used in paleontology to describe a group of early mammals that possessed a unique dental morphology. The term "homodont" comes from the Greek words "homo," meaning "same," and "odont," meaning "tooth." This refers to the fact that the teeth of homodontine mammals were all similar in shape and size, unlike the heterodont dentition seen in many modern mammals, where teeth vary in shape and function.

The earliest known homodontine mammals appeared during the Late Triassic period, around 220 million years ago. They were small, insectivorous animals that lived in a time when dinosaurs were the dominant terrestrial vertebrates. Homodontines are believed to have been the ancestors of the more advanced mammals that emerged during the Jurassic and Cretaceous periods.

The dental structure of homodontines is characterized by a single row of sharp, conical teeth in both the upper and lower jaws. These teeth were likely used for grasping and tearing prey, such as insects and small vertebrates. The homodont dentition is thought to have been an adaptation for a diet of soft-bodied prey, which would have been more abundant during the Mesozoic era.

Fossils of homodontine mammals have been found in various parts of the world, including Europe, North America, and Asia. Some of the best-known examples include the genus Cimolestes, which is known from fossils found in China, and the genus Morganucodon, which is known from fossils found in North America.

Despite their unique dental morphology, homodontines are not considered to be a monophyletic group, meaning that they do not form a single evolutionary lineage. Instead, they are thought to represent a diverse array of early mammals that shared similar dental characteristics. As such, the term "homodontines" is often used as a convenient way to refer to this group of early mammals, rather than as a formal taxonomic classification.