Memes
If Nurture, Why Not More Variation in Human Culture?
Humanity is, of course, morally free to make and remake itself infinitely, but we do not do so. We stick to the same monotonously human pattern of organizing our affairs. If we were more adventurous, there would be societies without love, without ambition, without sexual desire, without marriage, without art. without grammar, without music, without st smiles—and with as many unimaginable novelties as are in that list. There would be societies in which women killed each other more often than...If humans have free will, then there should be cultures without love, musics, and other social norms.
We Inherit from Our Parent's Zygotes
It IS a mistake that biologists used to make, too. They believed that evolution proceeded by accumulating the changes that individuals gathered during their lives. The idea was most clearly formulated by Jean-Baptiste Lamarck, but Charles Darwin sometimes used it, too. The classic example is a blacksmith's son supposedly inheriting his father's acquired muscles at birth. We now know that Lamarckism cannot work because bodies are built from cakelike recipes, not architectural blueprints, and i...The failure of Lamarkism means we do not inherit our genes from our parents, but from their sex cells.
Genetic Similarity Among All Humans
Every human being has two parents, four grandparents, eight great-grandparents, sixteen great-great-grandparents, and so on. A mere thirty generations back—in, roughly, A.D. 1066—you had more than a billion direct ancestors in the same generation (2 to the power of 30), Since there were fewer than a billion people alive at that time in the whole world, many of them were your ancestors two or three times over. If, like me, you are of British descent, the chances are that most all of the fe...The genetic differences between those with the same geographic background exceeds the difference between those of different "races."
Evolution as a Constant Arms-Race
One of the peculiar features of history is that time always erodes advantage. Every invention sooner or later leads to a counterinvention. Every success contains the seeds of its own overthrow. Every hegemony comes to an end. Evolutionary history is no different. Progress and success are always relative. When the land was unoccupied by animals, the first amphibian to emerge from the sea could get away with being slow, lumbering, and fishlike, for it had no enemies and no competitors. But if a...Where the players are constantly evolving to stay in one place.
Marriage as a Partnership of Mutual Cooperation
The relationship between a mother and her child is fairly straightforward: Both are seeking roughly the same goal—the welfare of themselves and each other. The relationship between a man and his wife's lover or between a woman and her rival for a promotion is also fairly Straightforward: Both want the worst for each other. One relationship is all about cooperation, the ot other all about conflict. But what is the relationship between a woman and her husband? It is cooperation in the sense t...Where the father seeks to reproduce and the mother seeks a provider for the children.
Inter-Species Competition
A gazelle on the African savanna is trying not to be eaten by cheetahs, but it is also trying to outrun other gazelles when a cheetah attacks. What matters to the gazelle is being faster than other gazelles, not being faster than cheetahs. (There is an old story of a philosopher who runs when a bear charges him and his friend. "It's no good, you'll never outrun a bear," says the logical friend. "I don't have to." replies the philosopher. "I only have to outrun you.") In the same way, psycholo...Members of a species compete with one another as well as with other species.
Mullet's Ratchet
In recent years the geneticists have turned away from good mutations and begun to think about bad ones. Sex, they suggest, is a way of getting rid of bad mutations. This idea also has its origins in the 1960s, with Hermann Muller, one of the fathers of the Vicar of Bray theory. Muller, who spent much of his career at the University of Indiana, published his first scientific paper on genes in 1911, and a veritable flood of ideas and experiments followed in the succeeding decades. In 1964 he ha...Without sex, mutations would ratchet up. An infusion of good genes from another source keeps them clean.
Sex as a Survival Strategy
In 1966, George Williams exposed the logical flaw at the heart of the textbook explanation of sex. He showed how it required animals to ignore short-term self-interest in order to "further the survival and evolution of their species, a form of self restraint that could have evolved only under very peculiar circumstances. He was very unsure what to put in its place. But he noticed that sex and dispersal often seem to be linked. Thus, grass grows asexual runners to propagate locally but commits...Many species that are asexual become sexual when it is time to disperse over large distances.
Competition Causes Death
Biologists have persistently overestimated the importance of physical causes of premature death rather than biological ones. In virtually any account of evolution, drought, frost, wind, or starvation looms large as the enemy of life. The great struggle, we are told, is to adapt to these conditions. Marvels of physical adaptation—the camel's hump, the polar bear's fur, the rotifer's boil-resistant tunare held to be among evolution's greatest achievements. The first ecological theories of sex...Animals die from competition with other animals, few die of natural causes.
Parasititic Influence on Evolution
Again and again in recent years evolutionary biologists have found themselves returning to the theme of parasites. As Is Richard Dawkins put it in a recent paper: "Eavesdrop [over] morning coffee at any major centre of evolutionary theory today, and you will find 'parasite' to be one of the commonest words in ti the language. Parasites are touted as the prime movers in the evolution of sex. promising a final solution to that problem of problems.'" Parasites have a deadlier effect than preda...Parasites are small and numerous, evolving faster than we do and putting incredible evolutionary pressure on the species they plague.
Two Sexes is Inefficient
Many fungi are sexual, but they do not have males. They have tens of thousands of different sexes, all physically identical, all capable of mating on equal terms. but all incapable of mating with themselves. Even among animals there are many, such as the earthworm, that are hermaphrodites. To 3e sexual does not necessarily imply the need for sexes, let alone for just two sexes, let alone for two sexes as different as men and women. Indeed, at first sight, the most foolish system of all is two...Fungi have thousands of different sexes, making almost everyone a potential partner, for humans, 50% of people are not potential partners.
A Bizarre Genetic Parasite
Another insect, a scale insect, has an even more bizarre genetic parasite. When its eggs are fertilized. sometimes more than one sperm penetrates the egg. If this happens, one of the sperm fuses with the egg's nucleus in the normal way; the spare sperm hang around and begin dividing as the egg divides. When the creature matures, the parasitic sperm cells eat out its gonads and replace them with themselves. So the insect produces sperm or eggs that are barely related to itself, an astonishing ...Something strange happens when two scale insect sperm fertilize an egg.
The Give and Take of Gender on Evolution
Trivers and Willard realized that the same general principle of sex allocation, which determines the gender of nematodes and fish, applies even to those creatures that cannot change sex but that take care of their young. They predicted that animals would be found to have some systematic control over the sex ratio of their own young. Think of it as a competition to have the most grandchildren. If males are polygamous, a successful son can give you far more grandchildren than a successful daugh...Males can produce more offspring, but if there are too many males, then their chances are reduced and it is preferable to have a girl.
Environmental Influence on Gender
There are many well-established natural factors that bias the sex ratio of human offspring, proving that it is at least possible. The most famous is the returning-soldier effect. During and immediately after major wars, more sons are born than usual in the belligerent countries as if to replace the men that died. (This would make little sense; the men born after wars will mate with their contemporaries, not with those widowed by the war). Older fathers are more likely to have girls, but older...Various environmental stresses that cause pregnancies to produce more females.
Why Women Store Fat in their Hips and Breasts
Low was looking to explain why young women have fat on their breasts and buttocks more than on other parts of their bodies. The reason this requires explaining is that young women are different from other human beings in this respect. Older women, young girls, and men of all ages gain fat on their torsos and limbs much more evenly. If a woman of twenty or so gains weight, it largely takes the form of fat on the breasts and buttocks; her waist can remain remarkably narrow. So much is undispu...Young women deceive men about their sexual fitness with fat to make their hips look wider and their breasts larger.
Ways to Understand Male Sexuality
There are five ways to find out. One is to study modern people directly and describe what they do as the human mating system The answer is usually monogamous marriage. A second way is to look at human history and divine from our past what sexual arrangements are typical of our species. But history teaches a dismal lesson: A common arrangement from our past was that rich and powerful men enslaved concubines in large harems. A third way is to look at people living in simple societies with Ston...Different ways to understand where human males fall along the sexual spectrum.
Four Rules of Mating and Paring Strategy
Let us erect the four commandments of mating system theory. First, if females do better by choosing monogamous and faithful males, monogamy will result—unless, second, men can coerce them. Third, if females do no worse by choosing already-mated males, polygamy will result—unless fourth already-mated females can prevent their males fro monogamy will result. The surprising conclusion of game theory is therefore that males, despite their active role in seduction, may be largely passive spect...Various environmental influences that determine polygamy vs monogamy, etc.
The Harems of Ancient Cultures
But when she examined the record of history, Betzig was stunned. Her simplistic prediction that power is used for sexual success was confirmed again and again. Only in the past few centuries in the West has it failed. Not only that, in most polygamous societies there were elaborate social mechanisms to ensure that a powerful polygamist left a polygamous heir. The six independent "civilizations" of early history—BabyIon, Egypt, India, China, Aztec Mexico, and Inca Peru—were remarkable le...A strong argument for power influencing access to reproduction.
Orgasms and Sperm Retention
t. Baker and Bellis discovered that the amount of sperm that is retained in a woman's vagina after sex varies according to whether she had an orgasm and when. It also depends on how long it was since she last had sex: The longer the period, the more sperm stays in, unless she has what the scientists call "a noncopulatory orgasm" in between. So far none of this contained great surprises; these facts were unknown before Baker and Bellis did their work (which consisted of samples collected by ...Women retain more sperm when they have an orgasm, but they are also more likely to be unfaithful when most fertile.
Brain Differences Between the Genders
There are three reasons to expect evolution to have produced different mentalities in men and women. The first is that men and women are mammals, and all mammals show sexual differences in behavior. As Charles Darwin put it, "No one disputes that the bull differs in disposition from the cow, the wild boar from the sow, the stallion from the mare."' The second is that men and women are apes, and in all apes there are great rewards for males that show aggression toward other males, for males th...Some dimorphism between the sexes as a result of evolution.
How Testosterone Affects the Brain
We last met the steroid hormone testosterone in fish and birds where it was rendering them more vulnerable to parasites by exaggerating their sexual ornaments. In recent years more and more evidence has been found that testosterone affects not just ornaments and bodies but also brains. Testosterone is an ancient chemical. found in much the same form throughout the vertebrates. Its concentration determines aggressiveness so exactly that in birds with reversed sex roles, such as phalaropes and ...Males are mutated females through the addition of testosterone.
Hormones on the Brain
At school, boys are fidgety, difficult, inattentive, and slow to learn, compared to girls. Nineteen out of every twenty hyperactive children are boys. Four times as many boys as girls are dyslexic and learning disabled. "Education is almost a conspiracy against the aptitudes and inclinations of a schoolboy," wrote psychologist Dianne McGuiness, a sentiment to which almost every man with a memory of school will raise a hearty cry of assent. But another fact begins to emerge at school. Girls a...How hormones affect learning in school children.
Genes versus Hormones in Homosexuality
It is clear, however, that the cause of homosexuality lies in some unusual balance of hormonal influence in the womb but not later on, a fact that further supports the idea that the mentality of sexual preference is affected by prenatal sex hormones. This is not incompatible with the growing evidence that homosexuality is genetically determined. The "gay gene" that I will discuss in the ext chapter is widely expected to turn out to be a series of genes that affect the sensitivity of certain t...Are the genes for homosexuality like the genes for height? Not a predetermined thing, but putting us in averages?
Male and Female Differences on Pornography
Hard porn, which depicts actual acts of sex, is almost invariably about the gratification of male lust by willing, easily aroused, varied, multiple, and physically attractive women (or men, in the case of gay porn). It is virtually devoid of context, plot, flirtation, courtship, and even much foreplay. There are no encumbering relationships, and the coupling duo are usually depicted as strangers. When two scientists showed heterosexual students pornographic films and measured their arousal by...Males prefer pornography, while women prefer romance novels.
Human Pairs Must Keep Each Other Interested
Likewise, the manner in which sexual selection capriciously seizes upon preexisting perceptual biases fits with the fact that apes are by nature naturally "curious, playful, easily bored, and appreciative of simulation." Miller suggests that to keep a husbanc around long enough to help in raising children, women would have needed to be as varied and creative in their behavior as possible, which he calls the Scheherazade effect after the Arabian storyteller who entranced the Sultan with 1,001 ...Men and women in marriage seek to keep each other entertained to retain interest.
Writing as Quilting
This book is crammed with original ideas—very few of them my own. Science writers become accustomed to the feeling that they are intellectual plagiarists, raiding the minds of those who are too busy to tell the world about their discoveries. There are scores of people who could have written each chapter of my book better than I. My consolation is that few could have written all the chapters. My role has been to connect the patches of others' research together into a quilt.Taking ideas and patching them into the quilt of a book.
If Humans were Like Sparrows
It is my contention that man is just like an ibis or a swallow or a sparrow in several key respects. He lives in large colonies. Males compete with one another for places in a pecking order. Most males are monogamous. Polygamy is prevented by wives who resent sharing their husbands lest they also share his contributions to child rearing. Even though they could bring up the children unaided, the husband's paycheck is invaluable. But the ban on polygamous marriage does not prevent the males fro...The sexual habit differences and similarities.
If Humans Were Like Chimpanzees
If we were hairless chimpanzees, our society would still Dok fairly familiar in some ways. We would live in families, be very social, hierarchical, group-territorial, and aggressive toward other groups than those we belong to. In other words, we would be family-based, urban, class-conscious, nationalist, and belligerent, which we are. Adult males would spend more time trying to climb the political hierarchy than with their families. But when we turn to sex, things would begin to look very dif...Much would be the same, but we would be very different sexually.
Humans are a Self-Domesticated Animal
Mankind is a self-domesticated animal; a mammal; an ape; a social ape; an ape in which the male takes the initiative in courtship and females usually leave the society of their birth; an ape in which men are predators, women herbivorous foragers; an ape in which males are relatively hierarchical, females relatively egalitarian; an ape in which males contribute unusually large amounts of investment in the upbringing of their offspring by provisioning their mates and their children with food, p...A list of the behaviors in human beings.
The Waist-to-Hip Ratio
Why does the waist-to-hip ratio matter? Singh observes that a "gynoid" fat distribution—more fat on the hips, less on the torso—is necessary for the hormonal changes associated with female fertility. An "android" fat distribution-—fat on the belly, thin hips—is associated with the symptoms of male disabilities such as heart disease, even in women. But which is cause and which effect? It seems to me more likely that both the shape and the hormonal effects of it are sexually selected by...Men are unconsciously directing the evolution of women.
Environment of Evolutionary Adaptedness
Then for more than a million years people lived in a way that couldn't have changed much. They inhabited grasslands and woodland savannas, first in Africa, later in Eurasia, and eventually in Australasia and the Americas. They hunted animals for food, gathered fruits and seeds, and were highly social within each tribe but hostile toward members of other tribes. Don Symons refers to this combination of time and place as the "environment of evolutionary adaptedness," or EEA, and he believes it ...We can only be adapted to the past, not the present or the future.
Cooperation VS Capitalism
Finding the right balance between cooperation and competition has been the goal and bane of Western politics for centuries. Adam Smith recognized that the economic needs of the individual are better met by unleashing the ambitions of all individuals than by planning to meet those needs in advance. But even Adam Smith could not claim that free markets produce Utopia. Even the most libertarian politician today believes in the need to regulate, oversee, and tax the efforts of ambitious individua...Human intelligence has yet to design a society where free competition among the members works for the good of the whole.
The Immune System VS Viruses
The immune system consists of white blood cells that come in about 10 million different types. Each type has a protein lock on it called an "antibody," which corresponds to a key carried by a bacterium called an "antigen." If a key enters that lock, the white cell starts multiplying ferociously in order to produce an army of white cells to gobble up the key-carrying invader, be it a flu virus, a tuberculosis bacterium, or even the cells of a transplanted heart. But the body has a problem. It ...An excellent description of the battle going on inside our bodies.
The Tangled Bank Theory
Michael Ghiselin developed this idea further in 1974 and made some telling analogies with economic trends. As Ghiselin put it, "In a saturated economy, it pays to diversify." Ghiselin suggested that most creatures compete with their brothers and sisters, so if everybody is a little different from their brothers and sisters, then more can survive. The fact that your parents thrived doing one thing means that it will probably pay to do something else because the local habitat might well be full..."In a saturated economy, it pays to diversify."
Hummingbirds are Proof of the Cost of Sex
If sex had no cost, hummingbirds would not exist. Hummingbirds eat nectar, which is produced by flowers to lure pollinating insects and birds. Nectar is a pure gift by the plant of its hard-won sugar to the hummingbird, a gift given only because the hummingbird will then carry pollen to another plant. To have sex with another plant, the first plant must bribe the pollen carrier with nectar. Nectar is therefore a pure, unadulterated cost incurred by the plant in its quest for sex. If sex had n...Plants offer nectar to hummingbirds in exchange for their role in plant sex.
A lot happens in 100k Years of Evolution
Inside my skull is a brain that was designed to exploit the conditions of an African savanna between 3 million and 100,000 years ago. When my ancestors moved into Europe (I am a white European by descent) about 100,000 years ago, they quickly evolved a set of physiological features to suit the sunless climate of northern latitudes: pale skin to prevent rickets, male beards, and a circulation relatively resistant to frostbite. But little else changed: Skull size, body proportions, and teeth ar...A brief descriptions of the characteristics acquired in 100,000 years of human history.
Reproduction is the Most Important Evolutionary Trait
Those strains that reproduce persist; those that do not reproduce die out. The ability to reproduce is what makes living things different from rocks. Besides, there is nothing inconsistent with free will or even chastity in this view of life. Human beings, I believe, thrive according to their ability to take initiatives and exercise individual talent. But free will was not created for fun; there was a reason that evolution handed our ancestors the ability to take initiatives, and the reason w..."Everything can be inherited except sterility."
Neoteny in Humans
...the concept of "neoteny"—the retention of juvenile features into adult life. It is a commonplace of human evolution that the transition from Australopithecus to Homo and from Homo habilis to Homo erectus and thence to Homo sapiens all involved prolonging and slowing the development of the body so that it still looked like a baby when it was already mature. The relatively large brain case and small jaw, the slender limbs, the hairless skin, the unrotated big toe, the thin bones, even the ...Adult humans look like baby chimpanzees