Final answer:
The mammalian cortex consists of six distinct layers, which contribute to the complex brain functions by allowing a high density of neurons, increased surface area, and the potential for advanced cognitive abilities in mammals.
Step-by-step explanation:
The mammalian cortex has 6 distinct layers of cells. These layers are part of the neocortex, which is responsible for many complex brain functions. In some mammals, like rats, the neocortex is relatively smooth, while in others, like humans, it has many folds that increase the surface area.
The cerebral cortex, particularly the neocortex, is a critical region of the mammalian brain that has a significant role in many complex brain functions. This layer is highly developed in mammals and is especially remarkable due to its laminar structure that consists of six distinct layers. Each of these layers has different types of neurons with various functions, ranging from receiving sensory information to sending out motor commands and processing complex cognitive tasks. In mammals, the size of the neocortex and its surface area, which includes folds known as sulci and gyri, can be indicative of an animal's mental abilities. Increased folding allows for more neurons to be packed into the cortex, contributing to higher intelligence and complex social behaviors in certain species like apes, whales, dolphins, and humans. Hence, the six-layered structure of the mammalian cortex is not only unique among vertebrates but also pivotal to a mammal's advanced cognitive capabilities.