Evolutionary neuroscience
Evolutionary neuroscientists investigate the evolution and natural history of nervous system structure, functions and emergent properties.
[2][3] In addition, evolutionary neuroscientists study the evolution of specific areas or structures in the brain such as the amygdala, forebrain and cerebellum as well as the motor or visual cortex.
The second major argument is that of Aristotle's scala naturae (scale of nature) and the great chain of being versus the phylogenetic bush.
[4] The field of evolutionary neuroscience has been shaped by the development of new techniques that allow for the discovery and examination of parts of the nervous system.
Santiago and Pedro Ramon used this method to analyze numerous parts of brains, broadening the field of comparative neuroanatomy.
In the second half of the 19th century, new techniques allowed scientists to identify neuronal cell groups and fiber bundles in brains.
[6](pp 1–2) Although the amphioxus' "brain" might seem severely underdeveloped compared to their human counterparts, it was set well for its respective environment, which has allowed it to prosper for millions of years.
Although many scientists once assumed that the brain evolved to achieve an ability to think, such a view is today considered a great misconception.
500 million years ago, the Earth entered into the Cambrian period, where hunting became a new concern for survival in an animal's environment.
[6](pp 5–6) As creatures acquired a variety of senses for perception, animals progressed to develop allostasis, which played the role of an early brain by forcing the body to gather past experiences to improve prediction.
Animals that had not developed allostasis would be at a disadvantage for their purpose of exploration, foraging and reproduction, as death was a higher risk factor.
[6](pp 14–16) Recent research in molecular genetics has demonstrated evidence that there is no difference in the neurons that reptiles and nonhuman mammals have when compared to humans.
Instead, new research speculates that all mammals, and potentially reptiles, birds and some species of fish, evolve from a common order pattern.
The reptilian brain, 300 million years ago, was made for all our basic urges and instincts like fighting, reproducing, and mating.
[6](pp 75–76) Research about how visual perception has developed in evolution is today best understood through studying present-day primates since the organization of the brain cannot be ascertained only by analyzing fossilized skulls.
For example, an on-edge soldier believes a young child with a stick is a grown man with a gun, as the brain's sympathetic system, or fight-or-flight mode, is activated.
If someone were to hear leaves rustling in a forest, the brain might interpret that sound as being an animal which could be a dangerous factor, but it would simply be another person walking.
Evidence of a rich cognitive life in primate relatives of humans is extensive, and a wide range of specific behaviours in line with Darwinian theory is well documented.
[7][8][9] However, until recently, research has disregarded nonhuman primates in the context of evolutionary linguistics, primarily because unlike vocal learning birds, our closest relatives seem to lack imitative abilities.
Evolutionary speaking, there is great evidence suggesting a genetic groundwork for the concept of languages has been in place for millions of years, as with many other capabilities and behaviours observed today.
Research has shown substantial evidence of well-defined neural pathways linking cortices to organize auditory perception in the brain.
As for studying this in relation to the human brain, it has been theorized that very specific social skills apart from language, such as trust, vulnerability, navigation, and self-awareness can also be passed by offspring.
