Early and recent primitive brain forms.
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D005075:Biological Evolution; D001921:Brain / Q000033:anatomy & histology*; D004292:Dominance, Cerebral / Q000502:physiology*; D005399:Fishes; D008959:Models, Neurological; D009474:Neurons / Q000648:ultrastructure; D011323:Primates