Procynosuchus

Procynosuchus was an early cynodont, a group of mammal-like reptiles that lived from the Late Permian to the Early Cretaceous periods. This genus, dating back to about 254 million years ago, is considered the first known cynodont. Fossils of Procynosuchus have been discovered in South Africa, Zambia, Germany, and Russia, indicating a wide geographic distribution.1

Cynodonts, including Procynosuchus, possessed several features that foreshadowed mammals. They had a secondary palate, allowing them to breathe while chewing, and differentiated teeth suited for chewing rather than just swallowing food whole. These traits suggest a higher metabolic rate and greater food requirements, similar to mammals. While their brains were still relatively small, their skeletal structure and jaw mechanics showed advancements towards mammalian characteristics.12