An Evolutionary Benefit to Self-deception

[div class=attrib]From Scientific American:[end-div]

We lie to ourselves all the time. We tell ourselves that we are better than average — that we are more moral, more capable, less likely to become sick or suffer an accident. It’s an odd phenomenon, and an especially puzzling one to those who think about our evolutionary origins. Self-deception is so pervasive that it must confer some advantage. But how could we be well served by a brain that deceives us? This is one of the topics tackled by Robert Trivers in his new book, “The Folly of Fools,” a colorful survey of deception that includes plane crashes, neuroscience and the transvestites of the animal world. He answered questions from Mind Matters editor Gareth Cook.

Cook: Do you have any favorite examples of deception in the natural world?
Trivers: Tough call. They are so numerous, intricate and bizarre.  But you can hardly beat female mimics for general interest. These are males that mimic females in order to achieve closeness to a territory-holding male, who then attracts a real female ready to lay eggs. The territory-holding male imagines that he is in bed (so to speak) with two females, when really he is in bed with one female and another male, who, in turn, steals part of the paternity of the eggs being laid by the female. The internal dynamics of such transvestite threesomes is only just being analyzed. But for pure reproductive artistry one can not beat the tiny blister beetles that assemble in arrays of 100’s to 1000’s, linking together to produce the larger illusion of a female solitary bee, which attracts a male bee who flies into the mirage in order to copulate and thereby carries the beetles to their next host.

Cook: At what age do we see the first signs of deception in humans?
Trivers: In the last trimester of pregnancy, that is, while the offspring is still inside its mother. The baby takes over control of the mother’s blood sugar level (raising it), pulse rate (raising it) and blood distribution (withdrawing it from extremities and positioning it above the developing baby). It does so by putting into the maternal blood stream the same chemicals—or close mimics—as those that the mother normally produces to control these variables. You could argue that this benefits mom. She says, my child knows better what it needs than I do so let me give the child control. But it is not in the mother’s best interests to allow the offspring to get everything it wants; the mother must apportion her biological investment among other offspring, past, present and future. The proof is in the inefficiency of the new arrangement, the hallmark of conflict. The offspring produces these chemicals at 1000 times the level that the mother does. This suggests a co-evolutionary struggle in which the mother’s body becomes deafer as the offspring becomes louder.
After birth, the first clear signs of deception come about age 6 months, which is when the child fakes need when there appears to be no good reason. The child will scream and bawl, roll on the floor in apparent agony and yet stop within seconds after the audience leaves the room, only to resume within seconds when the audience is back. Later, the child will hide objects from the view of others and deny that it cares about a punishment when it clearly does.  So-called ‘white lies’, of the sort “The meal you served was delicious” appear after age 5.

[div class=attrib]Read the entire article here.[end-div]