The Handicap Principle: A Missing Piece of Darwin's Puzzle

This is certainly one of the better books on evolution I have read recently. It is laid out in a remarkably cogent and logical manner, and the writing style is clear, crisp, and interesting. In the first chapter, the authors explain the problem they are trying to explain (why so many animals exhibit certain specific risky behaviours and traits, which at first glance seem counter-intuitive to evolutionary theory), and then present their thesis. Subsequent chapters are devoted to the systematic exploration of their hypothesis, while providing a fair and balanced examination of alternate explanations. Thus the book is a great example of the scientific method being implemented by true scientists, and the authors are to be congratulated for laying their ideas out so clearly and logically.

The risky behaviors and traits in question are those seen in animals like the springbok, the most fit of which literally taunt approaching predators by jumping straight up and down. For many years, this behavior was interpreted as altruistic; the idea being that these springboks were trying to warn the other springboks of the approaching danger.

The Zahavi's present an alternate explanation. They agree that the leaping springboks are definitely trying to send a message to their fellows, but it is not primarily intended to serve as a warning (although it may well serve that secondary purpose to some springboks in the back of the herd who have not yet seen the approaching lion.) The Zahavi's argue that these springboks are trying to show off, to communicate to their peers: "I am so fit, I can waste energy leaping around rather than simply running away. Lady springboks, you should come visit me after the danger has passed; male springboks, do not even think of messing with me." This is no different than the behavior seen in the fastest and most athletic kids playing a game of tag, when one of their slower fellows is "it." Who doesn't have the childhood memory of these kind of kids (usually boys) running around in circles about the hapless "it," dancing about him and taunting him (or her, but usually him), showing off to each other by making increasingly daring passes. Meanwhile, their slower, less fit peers have gotten as far away as possible, for those players know they dare not attempt such "risky" behavior.

Thus, these kinds of activities are all actually designed to increase status with one's peers, and as the Zahavis continue to show, we humans are programmed with the same tendencies as well. Here, I think, it is important to explain that evolutionary theory does not argue that these are consciously decided actions; rather, both we and animals are wired to behave this way, and we do so almost involuntarily. (Thus the handicap principle might explain why an otherwise intelligent person like Bill Clinton literally cannot keep it zipped. He really can't help himself, because among human males there is definitely a pecking order separating those who "score" from those who don't. This does not, of course, excuse the behavior, it simply explains it. But I digress.)

The handicap principle does, in fact, seem to explain a huge number of otherwise mysterious behaviors both in the animal kingdom and in human culture. The giant peacocks tail, or the rich men lighting their cigars with hundred dollar bills. The enormous, unwieldy rack of horns on a male deer's head during mating season, or the young man cruising for chicks in his $60,000 sports car. All designed to show off, to communicate that "I am so strong and successful I can waste resources on extravagances like this."

The Zahavi's even explain heroic, altruistic behavior in this context, and it is difficult to refute. The decision to run into a burning building and rescue someone never seems to be made deliberately - it usually appears to be an impulse - and yet the reward for the person who acts heroically and altruistically (if he survives the action) would, in fact, seem to make it worthwhile in the end. Thus, we may well be wired to impulsively act heroically because there is no doubt that a surviving hero is accorded greatly enhanced status, and the classic archetype of the fawning woman responding to such behaviour with coos of "my hero" shows that we all, deep down, know that such men do, in fact, get laid more often.

The Zahavis give countless examples such as this to explain curious traits and behaviors in the animal kingdom, and for my part, it appears to be an elegant explanation. Now comes the hard part, which the Zahavis acknowledge. The theory must withstand the exquisite scrutiny of scientific study, for it is not like we can interview springboks and ask them why they are leaping and jumping about when a lion approaches. Proving this theory beyond a shadow of a doubt will take time, and we are not yet there. But for the time being, this remains a compelling and viable explanation.

This book answers questions the kind bright children ask. I have based my peacock story and others on its fascinating observations. Clever, sensitive, appreciative and engaging facts about animals that make you think of people's communication and behavior. Who's cleverer?

This is a giant book. It will change your view of the world and there is no better outcome for reading. This book stirred my imagination and thinking. It is full of aha moments and it is devastatingly cold to fate of the human and the animal.

Extrapolating James A Shapiro's concept of "Natural Genetic Engineering", imagine that you are a quantum-consciousness-spirit designing your control cascades ( what's the wave, what's the float ? ).
Genetic Entropy is a problem. Quantum-consciousness only needs an infinitesimal amount of force to tweak things, by analogy to the force required to deflect an asteroid from a collision with earth, if your application of force is COHERENT you don't need a lot of force. So quantum-consciousness can fight Genetic Entropy, but only to a certain degree. What you need, is a MECHANISM to fight Genetic Entropy - how about Sexual Selection ?

Even Dawkins says that Sexual Selection is underrated, I think I saw that in an interview he did with David Attenborough. But what if Sexual Selection were DESIGNED by the peacock-spirit to fight Genetic Entropy, not so that evolution can move forward, that's way too difficult, but merely to avoid backsliding.

Why does the peacock grow that tail? Why does the springbok leap straight up into the air when it sees a predator? Why do people behave heroically? The handicap principle answers these questions, eloquently, simply and with an overwhelming sense of conviction. The peacock is advertising his fitness. He is saying to the female in essence, I am so fit I can carry around this cumbersome adornment and still scratch out a very fine living. The springbok is saying to the predator: don't even think about going after me. I am in such good shape I can waste energy jumping up and down and still have plenty of reserves to outrun you. Save us both the bother and go after someone weaker. (By the way, the springbok jumps straight up instead of sideways because by jumping straight up its performance can be effectively judged by a predator from any direction.) And the man who dives into the swiftly flowing river to save a drowning child is actually advertising his fitness and improving his station in society. He is so fit he can take chances that others dare not. He's the man the women want to mate with.

The Handicap Principle thus is about signals, signals between prey and predator, between one sex and the other, and between the individual and the group. The purpose of these signals is to display in an unequivocal way the fitness of the signaler. Note that such signals have to be "fake proof." They have to be what the authors call "reliable." An animal that can't run fast and has limited resources of energy can't waste them jumping in the air. It needs to get going immediately or to stay hidden if it is to have any chance of survival. A man leads with his chin. That's a signal that he's confident. When men had beards it was a little dangerous to stick your chin out since the other guy might grab your beard and you could be in trouble. People demonstrate wealth by wasting money. This is a "reliable" (if ugly) signal because without an ample supply of money, you can't afford to waste it.

Part of the beauty of this book comes from the personality of the authors, who spent a large part of their lives studying little babbler birds in Israel. I feel I know these little social birds just from the loving descriptions in the text. One can see that even though the Zahavis made their discovery of the handicap principle in 1975 and waited almost two decades before it was generally accepted in the scientific community, they harbor no bitterness, nor is their tone at all gloating. They come across as hard-working field scientists who love their work and nature.

Besides being full of exciting and original ideas, The Handicap Principle is also extremely well written. Each sentence is clear and to the point without the burden of unnecessary jargon or the wordy clumsiness sometimes found in such books. Amotz and Avishag Zahavi took great pride in effectively communicating their ideas to a wide audience. Additionally there are scores of exquisite, loving little black and white drawings by illustrator Amir Balaban of animals, birds, insects and people, etc., illuminating the text.

If you're interested in evolutionary theory, this is a book not to be missed. As Jared Diamond says on the cover, "Read this fine book, and discover what the excitement is all about."

--Dennis Littrell, author of "Understanding Evolution and Ourselves"