The Evolution of Brain and Intelligence

"Compared with other mammals, human beings have large brains and access to types of intelligence that other animals cannot even contemplate. The emerging consensus is that the human brain is large and complex, but not bizarrely so compared with other species of interest. The brains of orca whales, for example, measure up to human brains to such a degree that we, as a species, have little reason for self-congratulation."

"As to intelligence, interspecies comparisons are complicated by the fact that different species have evolved intelligences that are adapted to their respective ecologies. In the bat ecology, for example, a bat is much smarter than a person. The standard impression that humans are overall smarter than other animals must therefore resort to indirect types of evidence and argument if it is to be convincing."

"For over a century, scholars have proposed myriad ways in which humans are cognitively unique, not only when compared with other mammals but even compared with our large-brained extinct cousins, the Neanderthals. Here, the emerging consensus is that besides similarities and continuities between animal and human cognition, there are also radical differences, mainly in the domain of symbolic reasoning."

Human beings possess large brains and distinctive forms of intelligence compared to other mammals, though scientific measures reveal the human brain is not bizarrely exceptional relative to other species like orca whales. Brain comparisons involve multiple factors including absolute size, body-relative size, structure, morphology, complexity, and neuron count. Intelligence comparisons across species are complicated because different animals evolved cognitive abilities suited to their specific ecological environments. While bats demonstrate superior intelligence within their ecology compared to humans, humans show cognitive uniqueness primarily in symbolic reasoning capabilities. Scholars have identified radical differences between human and animal cognition, particularly regarding symbolic reasoning, though continuities also exist between animal and human cognitive abilities.

Read at Psychology Today