At Scientific American: “Cocktail of Brain Chemicals” may be key to what makes us human
|January 25, 2018||Posted by News under Human evolution, Intelligent Design, Mind|
From Bret Stetka at Scientific American:
A study that compares us with other primates finds a brain region linked to social behavior that may offer a biological explanation for why humans, not chimps, produced Shakespeare, Gandhi and Einstein
Something is going wrong already if we think that the difference between human beings and gorillas is measured by extreme outliers.
Raghanti and Lovejoy believe the human brain’s neurochemical profile was shaped by natural selection due to the various reproductive and survival benefits it conferred. Our evolving chemical signature, they suggest, allowed us to outcompete other apes and early hominins, referring to the numerous humanlike species that arose after our split with chimpanzees over six million years ago.
The team speculates humans’ elevated striatal dopamine levels in particular would have led to more advanced social behaviors and perhaps monogamy, both of which may have improved our offspring’s survival and benefitted our ancestors. They also feel that by enhancing social behaviors, a “dopamine-dominated striatum” personality type, as they call it, would have led to selection for increased brain size and also language.
To follow up their study, Lovejoy and Raghanti plan to test their idea on deceased apes who have had their behavior monitored throughout life. If their idea holds, more monogamous primates should have higher dopamine levels whereas the more territorial and aggressive among our evolutionary cousins should have elevated acetylcholine. More.
Hmmm. If we fed these cocktails to a gorilla’s brain, what would happen?
See also: Human Origins: The War of Trivial Explanations
The overarching theory in biology has been, for over a century, Darwinian evolution: Natural selection acting on random mutation is the cause of all or most variation in life forms. As anyone who has monitored what the media says over the years will know, all evidence is either interpreted on its terms or ignored. Thus, humans are evolved primates, an unexceptional twig on the tree of life, though like other twigs, we are accidental outliers.
The obvious problems with all of these disunited and discordant theses can be summed up for convenience as: 1) If some aspect of chimpanzee behavior explains matters, why didn’t it produce the same result in chimpanzees? 2) If mere advantage (which every primate seeks) explains a development like the human mind, why did only humans experience it? More.
Why human evolution happened only once: the question no one has to answer
Naturalism and the human mind