This was Wilson’s second to the last original book, and it’s quite short, perhaps simply a long essay; 125 pages divided into 7 chapters with illustrations and blank pages in between; many references, and an index.

Key Points

  • The gist here is that the big story of human evolution is what explains – is all that’s needed to explain – the human condition, individuals as well as societies. He’s stepping as far back as possible, taking the big picture. Societies formed via the same principles of selection and survival that created individual human nature.

  • He extends the ideas of THE SOCIAL CONQUEST OF EARTH (2012), which was about the idea of “eusociality,” the way some insects and a few mammals develop cultures through kinds of altruism and the dynamic between individual selection and group selection. He extends the ideas in that book to an extent, e.g. referencing a 2013 article by him and others that he claims disproves the mathematical basis for the early idea of kin selection.
  • Boiled down even further, the conclusion Wilson (and IIRC others) reached in the past couple decades is that social bonding has been the key to human intelligence – not, as long thought, tool-use (e.g. recall how 2001: A Space Odyssey implies that the use of tools, beginning with that bone to kill the prey, was the trigger to greater human intelligence).




  • All questions of philosophy about the human condition come down to three questions: What are we; what created us; what do we ultimately wish to become. The answer to the third requires accurate answers to the first two. Author has come to understand why even the wisest thinkers have not answered these questions, and why they have been so easily enslaved by religious and political dogma. Religion has claimed the answer to the meaning of human existence: the gods put us on earth and told us how to behave. “Why should people around the world continue to believe one fantasy over another out of the more than four thousand that exist on Earth? The answer is tribalism, and, as I will show, tribalism is one consequence of the way humanity originated.” P10. Each tribe has its history and moral lessons that are considered superior to all competing stories. “The members of the tribe are inspired by the special status the story gives them, not just on this planet but on all other of the multitude of planets in each of the trillion galaxies estimated to compose the known universe.”
  • Darwin’s ideas were shocking at first but have proven to be true, and extended to discoveries about how altruism and cooperation evolved. Author will also discuss what was the force that made us; what replaced the gods?

1, The Search for Genesis

  • We need a full and correct self-understanding of the emergence of our species. Every part of the human body and mind has a physical basis obedient to the laws of physics and chemistry, and it all originated through evolution by natural selection.
  • Evolution, the change in frequency of genes in populations, works at multiple levels. Individuals compete; and groups compete against other groups. Natural selection is ‘mutation proposes, the environment disposes.’ A trait might be totally heritable, like eye color, skin color a bit less than total, and personality and intelligence only middling heritability. Evolution can create a new species in a generation, or preserve some species unchanged for millions of years. Phenotopic flexibility is how a trait might be changed by interaction with the environment; it includes prepared learning, as when young animals imprint on their mothers (or whatever else they first see). Extreme examples include worker ants, who don’t reproduce themselves, but who help the entire colony survive, as Darwin perceived.

2, The Great Transitions of Evolution

  • These are the origin of life; complex cells; sexual reproduction; multi-cellular organisms; societies; language. The first is broadly conceived, with uncertainty about the details. Current opinion favors the formation of life in underwater volcanic vents. We will know much more when biologists can synthesize life in the lab, and when or if we discover life on other worlds. …brief descriptions of the following steps.
  • Cooperation among individuals includes interactions such as kin selection, direct reciprocity, and indirect reciprocity. Only our species has invented language, in a blink of geological time.

3, The Great Transitions Dilemma and How It Was Solved

  • The dilemma is, how can altruism arise by natural selection? Among humans, the soldier killed in battle, a monk’s vow of abstinence, “the ferocity of self-negating patriotism and religious faith” p43. It’s analogous to the various cells that form an organism, in cooperation; if each cell reproduced selfishly, you have cancer. The transition dilemma was solved in evolution at least half a dozen times. A second dilemma is why, when evolution in principle can proceed very rapidly, the major transitions took so long, from millions to billions of years. The potential contest of individual vs. group pervades all levels of life, from cells to empires (thus textbooks of the social sciences).
  • The answer isn’t completely clear, but the improbability of components falling into place explains why the transitions take so long. The solution involves multilevel selection, with understanding advanced through research mostly conducted in the current century.

4, Tracking Social Evolution Through the Ages

  • So what is the evidence? We look at tens of thousands of contemporary species, at every level of social complexity. Very basic are swarm insects, of types almost invisible. Then, feeding groups like starlings; flocks ‘roll’ as more experienced ones move forward. Food supply is increased; safety from enemies; their tight swarm thwarts hawks.
  • Even bacteria exhibit quorum sensing. Social mammals can think ahead, recognize other members personally, and plan actions relative to the group and to individuals within it, as a variety of investment strategies. These are acquired as predisposed learning, e.g. rules for young males, p59b.
  • Animal groups have been observed to last for years, e.g. a flock of birds in French Guiana for 17 years.
  • Only a very few have evolved to ‘eusocioality’, in which the colony is divided into a ‘royal’ caste for reproduction and a ‘worker’ class that performs the labor. These have developed the most advanced levels of altruism and social complexity.

5, The Final Steps to Eusociality

  • This would happen as some number of individuals withdrew from personal reproduction. The final step did *not* involve close kin of family members; rather the close kinship followed from the origin of eusociality.
  • About 2% of all insect species are eusocial. How recently they evolved was not realized until the 1970s. Insects arose as land-animals; then developed flight; then metamorphosis. Insects evolved 415mya; with no evidence of eusocial life until 252mya.
  • Only 17 independent origins of eusocial animals are known, p68.
  • Evidence that humans are eusocial includes the postmenopausal ‘caste’ of grandmothers; the cases where individuals join professions or callings that counter their own reproduction; homosexuals; and monastic orders in religions. Further evidence may be found, but the proportion is likely to remain very small.
  • A key to the origin of these lines is that they first developed progressive care of young in nests from egg to maturity for feeding, inspection, and protection. What starts as nests to store food develops to mothers staying with offspring, with the latter performing the labor to keep her alive.
  • So the behavior isn’t driven by close kinship, but the shift in behavior from separating when their offspring reach maturity.
  • Studies of solitary bees forced together experimentally show a propensity to behave eusocially—by dividing up the labor, as individuals move from one job to another, or take jobs not already being performed.
  • As eusociality begins, there is a tug-of-war between the interests of the individual worker and that of the colony. In obligatory eusociality, the worker never reproduces and the colony becomes a superorganism, as in various kinds of ants.

6, Group Selection

  • Understanding our own species has been stymied by two mysteries. The first, largely solved by Darwin, was the origin of advanced societies, of altruism; thus group selection, in which the sacrifice of some individuals gives the group an advantage over other groups. The second is, why then has eusociality been so rare? Why has not the common situation of a mother raising her young in a nest, led to eusociality?
  • The reason may be that, even if a mutation takes place to keep the mother and daughters together, the entire rest of the genome is adapted to solitary life.
  • Various studies show that, p84, advanced social organization entails an increase in the complexity of the genes affecting social behavior.
  • The way for altruism, division of labor, and cooperation among members is through group selection, as in competition between different ant colonies.
  • Review of group selection; within groups, selfish individuals win against altruists, but groups of altruists beat groups of selfish individuals, p87.
  • Studies of group selection include wolves in Yellowstone; fire ants; etc. Bizarre examples of spiders that live on communal webs. Termites can be assessed as social cockroaches.
  • A great controversy has festered within sociobiology ever since Haldane in the 1950s described a thought experiment about rescuing a drowning man—the idea of kin selection. Hamilton in the 60s refined this to an equation. But the theory is flawed and has been rejected more recently, p101; the equation can’t predict anything.

7, The Human Story

  • Out of some half a billion species of large animals, only one has reached the human level, and no further contest is possible.
  • Five to six million years ago, a single species of ape split into two, one leading to us, the other to chimpanzees and bonobos. Then came australopithecine, etc etc. Homo habilis 2-3mya, with a shift in diet. The savannah; lightning-struck fires that left charred meat. Defended campsites. Nest sites that led to increased brain size and eusociality. Division of labor; hierarchies. We can guess at the role of group selection by looking at the chimps and bonobos, e.g. warfare between chimps, that appears to be group selection. And so it works among humans, e.g. hunter-gatherer societies.
  • Of interest is the difference between ‘day talk’ and ‘night talk’ among those societies. The latter, mostly stories and myths, and the value of storytelling. From one or two hours a day in early species of homo, to four or five hours in modern humanity. Last line: “In short, longer social interaction is a key component in the evolution of a larger brain and higher intelligence.”

The book rather abruptly stops; there is no summary or wrap up, as if the author decided he’d made his point and had no need to belabor it. The book has some nice line drawings by Debby Cotter Kaspari.

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