Cynodonts are a group of therapsids that lived during the late Permian to the late Triassic periods. They are significant in the study of evolution because they are considered ancestors of modern mammals. Cynodonts exhibited features such as differentiated teeth and a more advanced jaw structure compared to their predecessors. These creatures were typically small and had a variety of adaptations that allowed them to thrive in different environments. Some cynodonts displayed characteristics like fur and possibly warm-bloodedness, which are traits associated with mammals. Their evolutionary success paved the way for the rise of true mammals in the Jurassic period.