The main idea here is to present idea of Eusociality that applies not only to humans, but also to other extremely successful forms of live –insects, especially ants. This idea helps to answer main philosophical questions humanity posed by referring to the process of evolution and not at the level of DNA only or even organism only, but at the level of society as whole with this process being broken into multiple levels, including competition between groups.
Author starts with defining the scope: “ALL QUESTIONS OF PHILOSOPHY THAT ADDRESS the human condition come down to three: what are we, what created us, and what do we wish ultimately to become.
“ Author believes that answers are in evolution and it is good not only for humans, but also for other forms of societies: ants and bees.
Chapter 1. The Search for Genesis
Here author presents his believes on key points for human self-understanding:
- Every part of the human body and mind has a physical base obedient to the laws of physics and chemistry. And all of it, so far as we can tell by continuing scientific examination, originated through evolution by natural selection.
- The unit of genetic evolution is the gene or ensemble of interacting genes. The target of natural selection is the environment, within which selection favors one form of a given gene (called an allele) over other forms (other alleles).
- During the biological organization of societies, natural selection has always been multilevel. Except in the case of “superorganisms,” as found in a few kinds of ants and termites, where subordinates form a sterile working class, each member competes with other members for rank, mates, and common resources. Natural selection simultaneously operates at the level of the group, affecting how well each group performs in competition against other groups.
Finally after that author discusses the key points of evolution: inheritance with variance and statistical selection of better breeders.
Chapter 2. The Great Transitions of Evolution
Here is how author defines the great transitions of evolution:
1.The origin of life
2.The invention of complex (“eukaryotic”) cells
3.The invention of sexual reproduction, leading to a controlled system of DNA exchange and the multiplication of species
4.The origin of organisms composed of multiple cells
5.The origin of societies
6.The origin of language
Author expresses his conviction that all teleological approaches to human evolution are false – the great transitions demonstrate that it is just natural process with no purpose whatsoever. He explains how each of these transition naturally occurred. Actually humans are not alone, huge number of other species moved along pretty far, with some all the way to level 5 and a few to level 6, albeit their language being very primitive, unlike human.
Chapter 3. The Great Transitions Dilemma and How It Was Solved
The dilemma here is about altruism and low probability of development of complex systems through multiple transitions. Author believes that it could be explained by evolution: “The solution begins with an appreciation of the enormity of the problem and the improbability, in fact near impossibility, of its solution. The great transitions together, composing the dragon challenge of evolution, lead through a field of extreme difficulty. Similarly, each of the transitions required almost unimaginably vast numbers of components (chemical compounds to simple living cells to eukaryotic cells and so on up), consuming long geologic periods of time, to create the next higher level. Each transition required, or at least was enhanced by, multilevel selection—occurrence of natural selection at the group levels added to selection at the individual level. “
Chapter 4. Tracking Social Evolution Through the Ages
Here author discusses formation of groups among various animals and their evolution. This process occurred many times so there is enough evidence to understand how it works. It seems to be done via: “…universal principle of modularity, the tendency of all biological systems to divide one way or another into semi-independent but cooperative groups. Members of the different groups specialize in function, even if just temporarily, in a way that serves the overall assembly as a whole and thereby on average benefits each individual singly”. Author believes that this process could lead to increase in groups’ complexity to the level, which is seldom achieved that he calls EUSOCIALITY. In Eusociality “the colony is divided into a “royal” caste specialized for reproduction, and a nonreproductive “worker” caste that performs the labor of the colony. Eusociality may be a relatively rare condition in evolution, but it has resulted in the most advanced levels of individual altruism and social complexity. It has conferred ecological dominance on the land by some of the species that possess it, particularly the ants, termites, and humans. “
Chapter 5. The Final Steps to Eusociality
Here author discusses evidence of Eusociality obtained from research of insects. He discusses difference between Eusociality and superorganisms such as Atta fungus and states that:” Eusociality, the organization of a group into reproductive and nonreproductive castes, occurred in only a tiny percentage of evolving lines, then relatively late in geological time, and almost entirely on the land. Yet
these few, leading to the ants, termites, and humans, have come to dominate the
terrestrial animal world. “
Chapter 6. Group Selection
Here is how author defines group selection:” Group selection is natural
selection of alleles (alternative forms of the same gene) that prescribe social traits. The traits favored by natural selection are those that entail the interaction of individuals within groups, including the initial formation of the groups. As groups of the
same species then compete, the genes of their members are tested, driving social evolution by natural selection up or down. A rich documentation of this process has been provided by both natural history and experimental studies. “
Then he provides support for this position both theoretically and referencing experimental studies in nature. Especially interesting are DNA studies on other Eusocial creatures – ants where prosocial behavior uses chemical communications based on DNA. Finally author provides some serious reasons for rejecting popular ideas of kin selection and inclusive fitness (Hamilton rule – General or HRG):
Chapter 7. The Human Story
The final chapter applies all this to human history: ”Humanity arose on the
African savanna from a line of australopiths by essentially the same route as the other known eusocial animals. A major driving force in social evolution was competition between groups, frequently violent. The final surge to the Homo level was enabled by the combination of an initially large brain, fire from the frequent lightning- struck savanna that could be captured and controlled, and the advantages of tightly gathered groups of cooperating members. “
To support idea of continuous process of violent competition between human groups author provides a very interesting table:
But it is not group violence that makes us human. Even more than that it was social interaction: ” From the earliest Homo formed, as brain size increased, the time devoted to social interactions likely increased. The trend upward has been inferred by Robin I. M. Dunbar of the University of Oxford. He used two correlations from existing species of monkeys and apes: first, time spent grooming as a function of group size, and second, the relation among apes between group size and cranial capacity. Extended to the australopithecines and the Homo line of species born from them, this method—admittedly tenuous—suggests that the “required social time” evolved from about one hour a day to two hours in the earliest species of Homo, thence four to five hours in modern humanity. In short, longer social interaction is a key component in the evolution of a larger brain and higher intelligence.”
MY TAKE ON IT:
I think that ideas expressed in this book are not just plausible, but actually completely correct. I do not see any other reasons for developing such huge and multifunctional tool for abstract thinking as human brain but for necessity to process complex tasks of strategizing, planning, communicating, and analyzing results. From current achievement in mathematics and computer science in modeling neural networks, it is clear that it requires huge amount of computing power. This is what evolution provided us with in the form of human brain. So far we used it relatively well, but now accumulated level of knowledge and skills become so big and sophisticated that it is a challenge for humanity to use it well enough to survive.