Barking Dogs And Crying Babies

If you’ve ever had a baby in your household, you know that humans are hard-wired to respond to the cries of an infant.

We can get used to tractor-trailers rumbling past our front door, or the 24-hour drone of a factory in the neighborhood, but there is something about the pitch and tone of a crying baby that cuts through all other noises and reaches down and sends an electric bolt to the nervous system. When Richard and Russell were in their cribs, their tiny, initial cries always jolted us instantly awake, no matter how tired we might have been.

IMG_1870Are humans similarly responsive to the barking of dogs? Kasey, unlike Penny, is a big barker. She barks when she wants food, she barks when food is being prepared, and she barks when she sees a stranger walking by or a cat stretching in our yard. Her shrill barks have an impact on my nervous system that is similar to a baby’s cries — they are disturbing and profoundly irritating.

There’s an evolutionary reason why we respond to baby cries, obviously. Human infants are helpless, and if evolution didn’t condition adults to react to their cries they would starve or be carried away by wolves, and the human species would cease to exist.

Could there similarly be an evolutionary reason why humans respond to a barking dog? Have dogs been domesticated for so long that natural selection has preferred humans who awaken when they hear the barking of man’s best friend and thereby can respond to whatever dangers the dog’s animal instincts have perceived?

I’m sticking with that theory, because it will be a lot easier to endure Kasey’s barking sprees if I believe that there is some Darwinism at work.


Dumb And Dumber

Are humans becoming dumber?  Some researchers think so, and argue that if a citizen of ancient Athens suddenly appeared in the modern world, they would seem unusually intelligent, well-balanced, and emotionally stable.

The arguments for an increasingly dim-witted human race are based upon a kind of reverse Darwinism — the world is now so safe, the theory goes, that the mutated dunderheads among us aren’t killed off and culled out, and therefore survive to reproduce where they wouldn’t have survived before — in combination with studies that show that certain common substances, such as fluoride in the water supply, pesticides, and processed foods, reduce intelligence.

Color me skeptical.  There’s no way of knowing whether the ancients were, in general, smarter than modern humans, but the arguments in support of that position seem pretty thin.  There seem to be medical studies that support just about any health conclusion you might want to reach, and if modern pesticides, fluoride, and processed foods are bad, there’s no telling how many people from ancient cultures were exposed to lead, poor sanitation, uncured illnesses, and other conditions that could impair brain functioning.

The natural selection argument doesn’t work, either.  If anything, the modern world is more dangerous to the witless than were the days of yore, where the village idiot could happily live out his days in the same tiny hamlet, guzzling mead and eating turnips.  The big killers — wars, plagues, and other pestilences — tended to kill the bright and the dull in equal measure.  Now, technology gives the imbeciles countless ways to knock themselves off, as the Darwin Awards recognize.  Why do you think modern devices feature so many unnecessary warnings?  The only reason lawnmowers caution people not to lift the lawnmower and use it to trim hedges is that some fool actually tried to do so at some point.

We citizens of the modern world may not all be rocket surgeons, but I see no evidence that we are any more stupid than our ancestors.  I don’t think the human race is quite ready to go the way of the Morlocks and the Eloi just yet.

Evolution Of Wusses

This article argues that modern males are pathetic – slower, weaker, with less stamina and body mass than our evolutionary forebears.  The evidence of this is a bit skimpy — relying, as it does, on one set of fossilized footprints that indicate that a long-ago aborigine, dubbed “T8,” ran about 40 miles per hour, as well as footage of members of an African tribe jumping their own height — but I have no doubt that humans who lived and hunted in the wild were faster, more accurate in throwing spears and rocks, and more capable of detecting, tracking, and bringing down game that could help to feed the tribe.  Evolutionary principles would suggest as much.  If survival to reproduce required physical stamina and endurance, athleticism, and hunting skills, you would expect natural selection to produce humans who fit that bill.  It has been centuries, and perhaps millenia, since western man has required to live solely on the proceeds of hunting and gathering, and therefore natural selection no longer focuses on such traits. 

Modern culture selects for different traits now.  So I say:  bring those aborigines on for a modern natural selection challenge!  I bet American men would kick some australopethicine butt in the shopping and can-opening events, and good luck finding much big game to feed the tribe in the wilds of New Albany, Ohio!  Let’s see if T8 can hold a job in this economy, compose a decent inter-office memo, or interact with members of the opposite sex without getting slapped with some kind of harassment lawsuit.  I bet the soft-in-the-belly modern male office worker can type faster, structure better computer searches, and speak more knowledgeably about the NFL at the water cooler than any hunter-gatherer.

So I say:  We are not wusses!  We are just naturally selected by overwhelming, irresistible historical and evolutionary forces to be plumper, slower and less studly than T8 and his buddies.  Those evolutionary forces may have made men more pathetic, but you have to admit — at least if the illustration accompanying this entry is even halfway accurate — it has worked wonders for the female of the species.

A Not-Now-Missing Link?

I love news articles about science, and as any reader of this blog knows, I particularly like Darwin’s theories because of their many potential uses. So, imagine my interest when I saw this article about the discovery of fossil remains of a creature that some scientists consider the “missing link” between the rest of the animal world and modern humans. Very cool! Notch another bit of tangible evidence in support of the theory of natural selection.

One admirable thing about real science is the willingness of scientists to disagree about theories and then test those disagreements through formulation of hypotheses and the use of the scientific method. So, it also was heartening to see that some scientists are downplaying, somewhat, the significance of the fossil find. Healthy disputes and vigorous debate are what science is all about.

Vegetable Week: Convenient Darwinism, Revisited

I have previously noted, see Convenient Darwinism, that the theory of natural selection is a flexible one that permits all kinds of odd arguments. For example, I would argue that we are genetically predisposed to crave meat. There is a biological basis for this argument. Scientific studies (see, e.g., here and here) suggest that the reason that the human brain evolved to its current size is because, at some point in the prehistoric past, the diets of human ancestors changed. These distant ancestors began to eat meat, and their brains grew. Indeed, some scientists conclude that the inclusion of meat in the diet, with its protein and high-caloric content, was essential to supporting the high-energy consumption qualities of the advanced human brain.

You could also argue that the theory of natural selection suggests that eating meat promoted bigger brains and keener intelligence for another reason. Eating plants doesn’t present much of an intellectual challenge. You see a plant, tear it out of the ground, and eat it. It is so unchallenging that the most tiny-brained creatures on Earth can do it. Eating meat, on the other hand, imposed much greater intellectual challenges. The animal from which the meat must be taken was desperately trying to avoid that fate, and therefore our ancestors needed to figure out how to track, trap, and kill the unwilling prey and then butcher and cook its meat. Those difficult tasks encouraged cooperation, language, social behavior, and the development of tools, among other things. The puny, weak-brained primates who couldn’t figure these challenges out were less likely to survive to reproduce; whereas the studly, brainy hunters thrived. And, from a social standpoint, the choices would be easy. If you were wandered across the savannah in Africa 2 million years ago, would you rather be a member of a dull-witted tribe that sat around munching dimly on grasses, ferns and brussel sprouts in a cold damp cave, or part of an active, fun-loving tribe that consumed sizzling haunches of meat around a roaring campfire and then, sated, talked animatedly about how to bring down that wild boar that had been seen around the neighborhood?

So, don’t listen to those who argue that our “natural” state requires a diet of vegetables. Stand up for bigger brains, social behavior, and tools! Stand up, and let your inner hunter/gatherer roar!

Convenient Darwinism

There has been a controversy recently in the Columbus suburb of Whitehall about whether the local schools should have a special recognition of the 200th birthday of Charles Darwin. The issue has devolved into the standard, tiresome, “debate” between evolution and creationism.

I sometimes wonder if those who oppose Darwin’s theories don’t fully realize how useful and convenient those theories can be. I appreciate the concepts of evolution and natural selection, in part, because they provide us with some useful excuses for traits that otherwise might reflect poorly on us as individuals. The underlying basis for all of the excuses is that we are the end product (at last, the current end product) of millions of years of natural selection, and that in many instances it is impossible for us to resist the biological imperatives that are produced by that evolutionary history.

Some years ago, I read a very interesting book that argued, among other things, that one reason modern American struggle with their weight is — surprise! — evolution. The author’s theory was that natural selection favored individuals who were very efficient producers of fat, because those individuals were thereby more likely to survive during the cycles of feast and famine that characterized most of human history. Now that we are in a time of plenty (at least, we were until the last six months or so), we can’t help being fat because our bodies were specifically selected to produce fat.

So, don’t blame me for that seemingly permanent beer belly. It’s the fault of my distant ancestor whose fat-producing qualities allowed him, or her, to survive when the rest of the tribe perished due to starvation. Whoo hoo!