PICTURE CREDIT PICTURE

An artist’s impression of the kind of social group in which early humans may have lived.

SOCIOBIOLOGY The distributed brain salutes the follow-up to a study on and hominin brain size.

ociobiology was born in 1975, when hominids to modern Thinking Big: How individuals to deceive and manipulate. In biologist Edward O. Wilson published Homo sapiens, which the Evolution of this view, the large brain is the product of an the volume that gave the field its name. has a ratio of brain to Social Life Shaped arms race that is a drain on species-level fit­ the Human Mind SThere are many social species, and we can body mass three times ness. Given the intense competition among CLIVE GAMBLE, JOHN gain insight into human sociality by compar­ that of other primates. GOWLETT AND ROBIN hominins to fill the hunter-gatherer niche, CCI ARCHIVES/SPL ing it with sociality in other animals. Large brains are very DUNBAR this theory of human hypercognition seems Several factors have propelled socio­ costly. Increased cra­ Thames and Hudson: implausible: the energy wasted in mutual biology to prominence in the behavioural nial capacity required 2014. deception would reduce human fitness, sciences. Perhaps most important was the the restructuring of favouring small-brained competitors. waning of a major impediment: the idea that the human birth canal and led to birth before In Thinking Big, Dunbar, Gamble and linking human behaviour to genetics fuels the fetus is fully matured. This in turn led to Gowlett supply a more credible theory with racist ideology. Furthermore, as researchers prolonged and collective child-rearing. In the their “social brain hypothesis”. They describe learned about the lives of birds, primates and average adult human, the brain represents the major findings of the ambitious 7-year insects, the concept of social structure as a about 2% of body weight, but consumes about project ‘Lucy to Language: The Archaeol­ general biological category arose. Finally, the 20% of calories. What could the counter­ ogy of the Social Brain’, which involved more value of interdisciplinary research such as balancing advantages of large brains be? than 30 researchers and 5 UK universities, became apparent in many areas The conventional answer has been skil­ and was backed by the British Academy, the in which complex systems cannot be under­ ful tool use. We now know, however, that national funding body for humanities and stood using the conventional field categories. hominin brain growth preceded by more social sciences. The authors show that there Sociobiology in Homo sapiens is espe­ than half a million years the emergence of is a strong correlation between relative neo­ cially complex because of the enormous part material culture — visual art, hafted tools, cortex volume and mean social-group size in played by culture in , which crafted containers and written language, all monkeys, apes and humans. They attribute is explored in gene–culture coevolutionary of which began to appear some 70,000 years this to the fact that the complexity of group theory. In Thinking Big — a follow-up to the ago. Richard Byrne and Andrew Whiten’s interactions increases with group size. A edited volume Social Brain, Distributed Mind Machiavellian Intelligence (Oxford Univer­ large brain gives individuals the means to (Oxford University Press, 2010) — Robin sity Press, 1988) insightfully shifted the focus forge strong social ties that enhance their Dunbar, Clive Gamble and John Gowlett from technical to social skills, suggesting that personal fitness and the group’s social explore the growth of the brain from early a sharp wit conferred fitness by enabling cohesion; in particular, a large neocortex

284 | NATURE | VOL 509 | 15 MAY 2014 © 2014 Macmillan Publishers Limited. All rights reserved BOOKS & ARTS COMMENT supports a “theory of mind”, whereby individuals can form mental representations of the beliefs and intentions of others. This Books in brief enables them to enter into complex agree­ ments and coalitions, and to track multiple The Butterfly Defect: How Globalization Creates Systemic Risks, social relationships through time and space. and What to Do about It Social Brain, Distributed Mind is rather Ian Goldin and Mike Mariathasan Princeton University Press (2014) more detailed. It brings together an array In a nod to chaos theory’s butterfly effect — in which tiny of archaeologists, anthropologists, geog­ perturbations unhinge big non-linear systems — this treatise raphers, psychologists, palaeontologists, explores globalization’s built-in risks. Economists Ian Goldin and Mike historians and philosophers involved in Mariathasan analyse systemic vulnerabilities leading to cyber-attacks Lucy to Language, who together construct or pandemics, and look at the ecological risks integral to globalization. a plausible “cognitive anthropology” that The sustainable management of such tangled interdependency, defends the social brain hypothesis, while they argue, demands governance reform, including the setting up of exploring the idea that the human mind is research-led bodies to tackle big issues such as climate change. not confined to individual brains, but lives in a social network of minds across which cognition is distributed. They thus handle The Third Horseman: Climate Change and the Great Famine of the the problem of brain growth long preceding 14th Century the emergence of material culture. William Rosen Viking (2014) The contributors argue that long before A kink in Europe’s climate during the fourteenth century indirectly material culture, early hominins developed triggered a seven-year cataclysm that left 6 million dead, William a “material memory system” in the form of Rosen reveals in this rich interweaving of agronomy, meteorology, tokens and containers. This linked the men­ economics and history. The Great Famine ended the explosion in tal power of many individuals, and led to a agricultural productivity of the 400-year Medieval Warm Period, transition from knowledge acquisition and which affected mainly North Atlantic civilizations. Rosen deftly learning based on personal discovery to cog­ delineates the backstory and the perfect storm of heavy rains, hard nition based on social interaction and shar­ winters, livestock epidemics and war leading to the catastrophe. ing. With distributed cognition, knowledge lies not only in the individual, but also in the social roles and iconic artefacts that link Birdmen: The Wright Brothers, Glenn Curtiss, and the Battle to minds. For instance, humans have formed Control the Skies ‘fission–fusion’ social groupings in which Lawrence Goldstone Ballantine Books (2014) kin relationships are maintained across The daredevil scientists and engineers who forged the field of subgroups, both males and females migrate aeronautics spring vividly to life in Lawrence Goldstone’s history. to marry, and complex, powerful, fitness- Wilbur Wright is famed for cracking the conundrum of powered, enhancing familial alliances are sustained. controlled, heavier-than-air flight through leaps of intuition and How plausible is the idea that we have big reasoning. Less known is his and brother Orville’s feud with ace flyer brains because we evolved to live in large and motor designer Glenn Curtiss. Goldstone never stints on the groups, putting heavy cognitive demands science in tracing the trio’s patent wars and struggles to monopolize on our ability to forge close social bonds the industry over a decade of dazzling innovation. with large numbers of individuals? My own view is that hunting required a high level of co­ordinated decision-making, and that the The Remedy: Robert Koch, Arthur Conan Doyle, and the Quest to presence of lethal weapons undermined Cure Tuberculosis our ape ancestors’ characteristic social- Thomas Goetz Gotham Books (2014) dominance hierarchy, which was based on What does germ theory have to do with evergreen fictional sleuth the physical prowess of the alpha male. This Sherlock Holmes? Science writer Thomas Goetz reveals all in this created a leadership void that could be filled history of the hunt to cure tuberculosis (TB), centring on young not by appeal to physical strength, but rather physician Arthur Conan Doyle’s 1890 trip to Berlin to report on by social persuasiveness and then a subtle bacteriologist Robert Koch’s TB remedy, tuberculin. Conan Doyle ability to form effective coalitions. rightly doubted its efficacy. But, impressed by Koch’s postulates that The result was a political structure in particular organisms cause diseases, he intensified his focus on the which linguistic facility and cognitive skills scientific method and the hunting of other insidious villains in fiction. were rewarded with enhanced reproductive fitness. The social brain, then, helped our ancestors to operate successfully in a proto- Cold Blood: Adventures with Reptiles and Amphibians democratic framework. ■ Richard Kerridge Chatto and Windus (2014) Nature writer Richard Kerridge fed, as a child, on accounts of black Herbert Gintis is external professor at rhinoceroses, red river hogs and mandrills. His native Britain lacked the Santa Fe Institute in New Mexico and such faunal glories — or so he thought, until he discovered the professor of economics at Central European glistening hordes of amphibians and reptiles lurking in grass, bogs University in Budapest. His most recent and leaf litter. In this mix of natural history, memoir and thoughts on book is A Cooperative Species (with Samuel the “cultural functions of wild animals for human beings”, captured Bowles). moments such as the golden flash of a palmate newt delight the e-mail: [email protected] reader as much as they did Kerridge’s childhood self. Barbara Kiser

15 MAY 2014 | VOL 509 | NATURE | 285 © 2014 Macmillan Publishers Limited. All rights reserved