tritylodontoids

Tritylodontoids are an extinct group of herbivorous cynodonts that lived from the Late Triassic to the Early Cretaceous periods. They are considered among the closest non-mammalian relatives to mammals. Their name, meaning "three-toothed grinders," refers to a distinctive molar structure featuring three parallel cusps. Fossil evidence suggests tritylodontoids were widespread, with remains found in various parts of the world.

These animals possessed a unique combination of reptilian and mammalian features. While they retained some reptilian skeletal traits, their dentition and likely endothermy point towards a closer relationship with mammals. Their skulls were robust, and they likely had strong jaw muscles to chew tough plant material. The development of triturating molars allowed them to efficiently process vegetation, a significant adaptation for herbivory.

Tritylodontoids varied in size, with some being small, rodent-like creatures, while others were larger, comparable to a badger. Their ecological role was likely that of a specialized herbivore within their ecosystems. The absence of further evolution in the tritylodontoid lineage suggests they were eventually outcompeted or were unable to adapt to changing environmental conditions or the rise of more advanced mammalian herbivores. Their study provides valuable insights into the evolutionary transition from synapsids to mammals.