As vertebrates evolved, the increasingly complex structure of the brain conferred increasingly complex function, especially apparent in the _. See Concept 49.3 (Page) View Available Hint(s) As vertebrates evolved, the increasingly complex structure of the brain conferred increasingly complex function, especially apparent in the _. See Concept 49.3 (Page) cerebral cortex, which is greatly expanded in humans, other primates, and cetaceans brainstem, which in most vertebrates, controls homeostasis and basic bodily function medulla oblongata, which controls automatic functions forebrain, which is a small brain region that arises early in development sleep-wake cycles of birds and mammals

The cerebral cortex, also known as the cerebral mantle (or gray matter), is the outermost layer of the brain in primates and other mammals. The cerebral cortex contains up to six layers of nerve cells and consists of approximately 15 billion neurons. This highly developed structure (cerebral cortex) is located in the forebrain, where is responsible for several complex functions including language and thinking processes.