COOPERATION AND THE EVOLUTION OF HUMAN NATURE

Bratman presents a compilation of scientific evidence and essays analyzing the evolutionary emergence of humans from apes.

This book, the second in a series (after Spontaneous Order and the Origin of Life, 2021) traces the nuances of evolution from the common ape ancestor shared by chimpanzees, bonobos, and humans to the point at which various branches—including human society—diverge. While past theories have focused on individual human intelligence as the reason for this particular separation, more evidence has emerged suggesting that the change was, in fact, due more to the need for cooperation. The author truly begins from the beginning, discussing cooperation at its most basic level with topics such as “cooperating genes in chromosomes” and “cooperation between individual cells in multicellular organisms.” He then moves on to “human-level cooperation,” comparing and contrasting it to behaviors in chimpanzees. While dense, the findings are inherently compelling, with constant connections being made between humans and nonhumans: “Some forms of cooperation that arise spontaneously are not susceptible to cheating. Flocking is the paradigmatic example. Such forms of immediate mutualism are likely the kernels out of which more advanced cooperation arises. But more complex cooperation requires means of cheater suppression. In current human society, much of this is accomplished via forms of strong reciprocity.” Once connections are made, it’s hard to stop making them; even the creation of language itself points to the probable existence of “prosocial drives” in long-ago human ancestors. The book concludes with four essays applying the evolutionary findings to relevant humanistic topics, such as evolutionary upgrades, the difficulties in solving collective action problems such as climate change, and our tendency to form our own groups within society.

The material discussed is, as one might expect, heavily scientific—it is by no means impenetrable, however. Bratman does an impressive job of presenting the findings in a way that is not overly technical without sacrificing the complexity and subtlety of the subject. There are many scientific studies referenced throughout supporting the particular points the author is making, including a fascinating example that illustrates the uniquely human desire to “solicit joint attention” from a parent or another child—juvenile chimpanzees don’t do that unless “they want another chimpanzee or human to do something for them.” Occasional pictures, including photos of early tools and hand-drawn diagrams demonstrating different modes of tool making don’t do much to break up the constant stream of information being presented—this is a subject that requires serious focus. Frequently, the insights into behavior are truly thought-provoking (and occasionally even amusing): “What chimpanzees truly excel at are the arts of politics. Their behavior is often described as Machiavellian, primarily focusing on food, sex and power.” This entry in Bratman’s series will likely appeal most to those who already have some basic grasp of how evolution works, but it certainly isn’t a requirement. The essays at the end help answer the “So what?” question that non-scientifically minded readers may find themselves asking.

A dense but fascinating read for anyone interested in biological and behavioral evolution.