Nimravines

Nimravines are an extinct subfamily of the cat family (Felidae) that lived in North America and Eurasia during the Oligocene and Miocene epochs, approximately 33.9 to 5.3 million years ago. They are distinguished by their specialized dentition, particularly the development of long, sabre-like upper canine teeth, although these were generally not as exaggerated as those seen in the true sabre-toothed cats (subfamily Machairodontinae). Nimravine canines were typically more slender and less flattened than those of machairodontines. Their skulls also featured a pronounced sagittal crest, a ridge of bone on top of the skull that served as an attachment point for powerful jaw muscles.

The nimravines are part of the Nimravidae family, which is an early radiation of feliform carnivorans. While they possessed some sabre-like teeth, they are not considered direct ancestors of modern cats and represent a separate evolutionary lineage that went extinct. Fossil evidence suggests that nimravines were predators, likely hunting medium to large herbivores. Their exact ecological role and hunting strategies are inferred from their skeletal anatomy, especially the musculature indicated by bone crests and muscle scars. Several genera are known, including Nimravus and Dinictis, with varying degrees of specialization in their sabre-tooth development and body size. The extinction of nimravines is thought to be related to climate changes and competition with other carnivores, including the ancestors of modern cats which were diversifying during the same period.