(Copyright © 2006 Piero Scaruffi | Legal restrictions - Termini d'uso )
The USA surgeon Leonard Shlain has written a book that is a fine example
of sociobiology at work. It mostly contains pure speculation (and in some
cases some obsolete beliefs) but the sheer amount of "speculative" ideas
is intimidating. Shlain behaves like an extremely rational detective
searching for a clue to a mystery, and using only his brain and a very
limited amount of clues in order to reconstruct what happened.
The whole process is fascinating precisely because of the questions that Shlain asks. There are so many oddities related to the behavior of the human female that anyone interested in evolutionary biology must wonder "why"? Shlain's book is basically a long list of such "oddities" and a long list of plausible answers. In a few instances the answers are not plausible, but not because his reasoning fails: either he is not aware of recent findings that could have helped him better direct his logic, or he speculates a bit too hard in the absence of evidence. Mostly, though, he makes a convincing case that the human species would be nothing but a bigger chimp if not for women's dramatic "oddities".
Basically, Shlain realized that we tend to examine the evolution of humans from the male perspective. We end up with a lot of mysteries as to why humans did what they did. He looks at it from the female perspective, and comes up with a lot of interesting solutions to those mysteries. If he is right, we owe our own consciousness, not to mention all of civilization, to the oddities of women's sexuality!
Shlain's line of argument is fundamentally that, because of the explosion in size of the human brain, women a) did not want to have children (they would die by the thousands while giving birth) and b) they desperately needed iron (a key ingredient of brains). Both factors caused women to develop strategies of mating that forced men to change their habits. The danger of giving birth led women to decouple sex and reproduction. The search for iron led females to favor men who could hunt and bring meat, a form of concentrated iron.
His motto is stated early on: "males tended to be what females wanted them to be".
The book begins by stating (in the preface) the ultimate paradox of the human female: she needs a lot of iron, but she loses a lot of it when she menstruates. No other female loses so much blood (and the ones who menstruate are a small minority anyway). What purpose can menstruating possibly serve? And why would menstruation be synchronized with the motion of the moon, a very distant object whose only visible effect on the Earth is the tide? The mystery remains unexplained till well the third part of the book (the one on Time, also the most controversial).
Shlain travels back in time (although he probably underestimates how much time has elapsed since then) to the day when a baby with a large-size brain was born to a woman whose pelvis was too small for it. Homo Sapiens posed a danger to the woman who gave birth to it. As he puts it, one of the leading causes of death among human females was and still is birth (where medical facilities are still primitive). This is clearly another paradox of nature: why should a mother be punished with death for giving birth to a child? This large-sized brain was the product of a random mutation but it must have turned out to be able to cope with the challenges of the environment better than the smaller brains (that presumably caused a smaller number of deaths among mothers) if today there are six billions of such large-size brains on this planet and they pretty much rule the planet. Shlain believes that evolution took care of the paradox not by modifying the body of the human female (the "natural" thing one would expect to happen is women with larger vaginas) but by modifying her behavior.
The females of the vast majority of species clearly signal to the males that they are ovulating and that therefore they welcome sexual attentions. Her signals (the "estrus"), that range from vocal sounds to bodily changes, arouse the males, and, therefore, increase the chances of having sex when it makes more sense for the purpose of reproduction (which is the only purpose known to almost all species expect for humans). The human female, though, is clueless about her period of ovulation: there is no physical evidence that she is ovulating. Neither is she aware of it, nor can the male be. No wonder that today sex and reproduction are uncoupled among humans to an extent unmatched by any other species. There are many more "oddities": the human female experiences orgasm, which is unknown to other species in that intense form; the human female has sex facing her partner; the human female has sex even "on top"; the human female experiences menopause (she stops ovulating altogether, i.e. of being able of making babies) relatively early in her life. Notably, the female of every other species copulates when it ovulates. The human female is the only one that decouples the two activities.
The larger-size brain of Homo Sapiens (mostly due to the appearance of the neocortex) was capable of new cognitive tasks. Shlain believes that it was women who first exploited the neocortex's new capability for reasoning. The human female realized something that no other species seem to have realized: the connection between sex and pregnancy. In women this was the connection between sex and the painful, life-threatening event of giving birth. Once women realized the connection (that each sexual intercourse could cause their death within nine months), they became less interested in sex than their counterparts in all other species. Basically, the human female became the first female capable of saying "no". Shlain believes that it was the woman, not the male, to undergo a major psychological and physical transformation because it was her life that was on the line.
Shlain believes that the human male reacted by developing strategies based on what "she" wanted and was willing to trade with sex. It turned out that the human female needed iron, lots of it, more than the previous ominids had been able to get from vegetables. Hence the human male became a hunter of animals and Homo Sapiens became an omnivore. Shlain believes the whole bloodthirsty nature of humans (from duels to genocides) is due to that original cause.
Males of other species are not interested in having sex with women who are not ovulating. Only the human male is constantly seeking sexual intercourse. The human male is also the only one to engage in convoluted forms of sex. Shlain believes that this sexual urge serves a purpose whose beneficiary is the female: because hunting was so dangerous and unnatural for humans, the man had to be highly motivated to risk his life hunting an animal on behalf of a woman. Nature motivated man by equipping him with an obsession for sex. Because he was constantly in need of sex, the human male was willing to go and hunt bigger and stronger preys despite his physical limitations.
As further evidence that humans were originally vegetarian, Shlain mentions a weak digestive system and an immune system that does not protect against the germs of rotting meat: no other animal has cook meat before eating it. Cooking requires fire. Shlain hints at the possibility that fire itself was invented to take care of women's passion for meat.
Another oddity of Homo Sapiens is that men reach their sexual peak when they are young (which makes sense because it's when they are producing the largest amount of sperm), whereas a woman's libido peaks in her 30s, when she is actually approaching menopause. It makes no sense that women want to have sex at an age when it would be wiser not to have children. Even more puzzling is that in all societies there seems to be a general preference for younger women among men and for older men among women. The net result is that no other species mansturbates so often as Homo Sapiens. Shlain has a simple explanation. The greatest threat to a young woman's life was an early pregnancy, because her body was not equipped for having babies with large brains. The greatest threat to a young man's life was hunting, because his body was not equipped for fighting with large, fast, strong animals. A reduced libido helped young women abstain until their pelvis grew larger. An increased libido prompted young men to go hunting.
Shlain believes that the orgasm of the human female, which is a unique phenomenon because of its intensity and duration, is nature's way to make a woman commit to the irrational act of having sex, an act that may cost her life when the baby is born. Since sex can be very pleasant, women have a motivation to do something that otherwise they would never want to do, thereby decreeing the extinction of the human race. (Shlain believes that this was the original purpose of circumcision, as circumcised men take longer to have an orgasm, thus giving women time to achieve their own).
(I would add that the asynchronous phases of sexuality between men and women may also explain cosmetics and fashion, both of which help women increase their appeal at an age when their physical appearance declines at the same time that their libido increases).
Shlain believes that female sexual behavior is also responsible for the evolution of the concept of time, and for memory in general. Shlain believes that humans are the only species that lives in a four-dimensional world. Plants live in a world with no space and no time dimensions. Primitive organisms capable of moving lived in a mono-dimensional space. Larger animals live in a three-dimensional space. But Shlain thinks that only humans are aware of Time because only humans can replay the past in their memories. The evolution of memory and the sense of time was vital for men to improve their ability to plan that was vital to become a successful hunter in a world of bigger, stronger and faster animals. Shlain thinks that this feature evolved was, again, driven by female sexuality: the monthly periodicity of menstruations served as a clock to "measure" time. Synchronizing them with the moon helped make them even more useful as a clock. (Homo Sapiens is among the few animals whose visual system and whose habitat make it easy to see the moon). Thus Shlain believes that menstruations ultimately helped humans evolve the temporal dimension and the cognitive ability of anticipating the future. The temporal package made them more efficient hunters.
Alas, the temporal dimension soon led to the realization of our mortality.
Another side-effect of the temporal dimension, according to Shlain, is that man became obsessed with paternity. As he realized what she had already realized, that a baby is the outcome of a sexual intercourse, he became paranoid about knowing this of her babies were his. Thus the escalation of laws meant to limit a woman's sexuality that make it easy for a man to know that her children are his. The institution of patriarchy followed shortly thereafter.
Shlain believes that language too had a sexual origin. As females became more aware of Time and of the implications of a pregnancy, language basically replaced hunting as a way for females to assess how good a mate each male would be. Shlain believes that the original purpose of language survive in today's habits, when men romance women while women mostly listen.
This, in a nutshell, is the story told in the book.
There is a downside to Shlain's creative exercise of what is clearly his fertile mind. A general rule of thumb is to be skeptic of "scholars" who do not publish in peer-review journals. It could be that the academia is too dumb to recognize a new genius, but it could also be that the scholar has not done his due diligence, and prefers to be carried away by his enthusiasm for his line of reasoning (and its appeal to a broad audience) than to be slowed down by criticism from the experts.
Thus Shlain makes statements about memory, the evolution of the human brain and the ubiquity of homosexuality that are haphazard at best. The weakest part of the book is probably the one about Time. Claiming that human females developed a sense of time before males goes against the entire historical and literary record, and goes against common sense too (ancient women did NOT know about menstruation, as they were virtually always pregnant or lactating and dying at about 30, menstruation and menopause becoming issues only in modern times).
Some of his logic may sound dubious, and mainly inspired by the society in which he (Shlain) grew up, not by the reality of billions of people around the world. For example, the idea that men wanted children to carry on after their death is a very modern and very Anglosaxon idea. In most "primitive" civilizations children are desired because they represent free labor, not necessarily because "they carry my genes". The dating system is an Anglosaxon oddity, hardly at work anywhere else (clearly he has never dated a Latina and never tried to marry an Indian girl). By the same token, Shlain does not spend a word on southern India, which has been vegetarian for centuries. Their children are perfectly fine (and some of them went on to win Nobel Prizes). The men do not provide any meat to their wives and nonetheless they enjoy some of the largest families on Earth.
The second half of the book detracts a bit from the charm of the first part. While the first part shocks the reader with a cascade of very simple albeit unexplained facts and some rather plausible explanations for them, the second part borders on pure imagination and rapidly becomes tedious in the attempt to explain just about everything that happened in human history. Shlain invokes Jung's theories (not exactly the peak of modern western science) and begins to sound like a sex-obsessed Freud when he speculates on homosexuality.
The first part alone, though, is worth it, because rarely has someone "outside the system" understood so much about what makes the system what it it.
TM, ®, Copyright © 2006 Piero Scaruffi