The Reptile brain is analogous to an avian brain and both are analogous to mammalian brain. —Dr. Erich Jarvis, School of Medicine and Neurosciences, Duke University.
Past models of brain structure and processes were envisioned like a layer cake. Reptiles were once considered to have primitive brains as were birds, hence the epithet “bird brain.”
Now, however, comparative neuroanatomy researchers such as Dr. Erich Jarvis have found that Lizards, Turtles, Crocodiles and Tortoises have brains comparable to our own.
We can now begin to explore reptile emotions, cognition, and experience of consciousness similar to how we might learn about different human cultures. Here is a table, Comparative Neuroanatomy of Mammals, Birds, Turtles, Lizards, and Crocodiles, that compares brain structures across species.