In times that test souls, people need all the self-assurance they can accumulate. So it is with ample measures of both gratitude and pride that we men and women of Western civilization should greet the news this week that our species is at its zenith. For us–the pampered, the prosperous, the privileged–human evolution is now deemed to be so last epoch.
The Daily Mail of Sydney, Australia, reported this week that a group of scientists now believe that “human evolution in the Western world is at a standstill and Darwin’s theory of natural selection no longer applies.” In the words of Steve Jones, a professor at University College, London, who was to advance this provocative assertion during a symposium in Edinburgh, Scotland, this week: “Things have simply stopped getting better or worse for our species. . . . We have reached stagnation.”
These suggestions of a halt to evolution apply only in the West. The story is different for less developed parts of the world where people aren’t so insulated from their natural environments.
By contrast with those people’s hardships, our soft lifestyle, insulation from nature and medical innovations get the credit for the alleged end of evolution. Here’s why:
In theory, humans best able to survive and thrive in their environments live longer lives, attract desirable mates and transmit the fittest genes to the next generation. But today, in Western countries, 98 percent of all children reach age 25. That suggests survival not only of the fittest genes, but of the least fit as well.
Example: Today a person afflicted with myopia, or nearsightedness, is often just a pair of eyeglasses away from adequate vision. So the myopia may survive for at least another generation. But long ago, says population biologist Richard Frankham of Sydney’s Macquarie University, “A myopic person might have been nabbed by some bloody carnivore.” And that tidy subtraction from the human gene pool would have made it slightly harder for myopia to survive.
Some scientists even contend that our fatty diets and physical inactivity may drive humans to regress, to evolve in a wrong direction. They envision people with smaller skeletons and thicker bodies. (Hint: If you chat about this theory with a potential mate, do so carefully.)
If it’s either that societal fate or an outright halt to evolution, the latter sounds even better.
And yet critics say the no-more-evolution theorists have it all wrong. They argue that evolution is an unpredictable and unstoppable imperative. Macquarie’s Frankham says technology and medicine have merely altered our environment, not rendered it inert. “The most important selection force has been disease and we are not totally disease free,” he says. “If something like ebola virus ever hit the spot, we would have some very rapid evolution.”
That presumably would yield a tougher breed of human. So perhaps our current generations aren’t the champions after all.
Still, that is a comedown with promise: We can hope that future humans won’t just be more disease-resistant, but a nobler bunch as well.
