Is Darwin Still Relevant? Advanced Human Brain Breaks Evolutionary Rules
Nasrallah, Henry A., Current Psychiatry
You may have noticed the buzz about Charles Darwin in the news: 2009 marks the 200th anniversary of his birth and the 150th anniversary of his monumental description of evolution in On the Origin of Species. Celebrations are scheduled around the world to honor the scientist who coined the phrase "natural selection" to explain the heritable process by which adaptive evolution occurs.
But is Darwin's theory of evolution still relevant? The "game-changer" that is transforming evolution is the genetic mutation that led to dramatic growth in the primate cortex--especially the frontal lobe--culminating in the emergence of Homo sapiens. The overdeveloped brain that has helped our species adapt and survive may be transforming us into predators of all other species and a hazard to our planet.
Survival regardless of'fitness'
Humans are discovering so much about biology and treatment of disease that we are disrupting natural selection and undermining the tyranny of "survival of the fittest." A triumph of modern medicine (the antithesis of eugenics) is salvaging those who in Darwin's day would have died and allowing them to survive and perpetuate their genes:
* Children born with metabolic errors no longer are doomed to succumb before their childbearing years.
* Premature 1-pound infants who never would have survived before are routinely doing so now.
* Women can conceive in their 60s, well after menopause.
* Medical advances have enabled humans to parry the deadly assaults of bacteria, viruses, and parasites.
* Future scientific advances will certainly include genetic engineering, which will eliminate the sometimes grim determinism of heredity.
Conversely, humans' intelligence has enabled us to wreak havoc on other species. Tens of thousands of animals and plants have vanished because flourishing humans have survived and wittingly or unwittingly exploited, polluted, and injured the environment. Of course, a pathologic evolution may backfire on us, despite our highly evolved brain. However, humans may still adapt and survive, albeit in a dramatically altered, even inhospitable world. Or maybe not, as war and weapons of mass destruction appear to be unique inventions of the human brain. …