Delving Into the Ancient Brain

NATURE|Vol 450|1 November 2007 BOOKS & ARTS

approach are original and provocative, and the Delving into the ancient brain suggestion rings true that the neurophysiological underpinnings of moods, motivations, and so on, were important during hominin cultural On Deep History and the Brain neurophysiological states that are important for and neurological evolution. by Daniel Lord Smail shaping human mental experiences. Hurford’s book, The Origins of Meaning, University of California Press: 2007. The contention here is that certain cultural also addresses an interdisciplinary audience, 286 pp. $21.95, £12.95 practices affecting brain–body chemistry extending to philosophers, psychologists, through psychotropic mechanisms are amena- anthropologists, cognitive scientists and The Origins of Meaning: Language in the ble to a neurohistorical approach. Palaeolithic ethologists. The topic of language origins is an Light of Evolution societies, for example, may have developed a intellectual minefield, and those who tread on by James R. Hurford range of mood-altering practices such as song, it need good balance — which Hurford has. Oxford University Press: 2007. 404 pp. dance, ritual, and ingestion of mind-enhancing Language, he neatly observes, allows humans $35 substances. Fast-forward to eighteenth-century to “go public with their thoughts”. Europe, when these were joined by caffeine, A large part of the book reviews the experi- Dean Falk sentimental novels, pornography and a grow- mental literature on the cognition of animals On Deep History and the Brain and The Origins ing array of consumer goods. Today we have to model the protolinguistic substrates that of Meaning are both concerned to some degree shopping, drugs and gossip. probably characterized our earliest hominin with the evolution of human behaviour and the Psychotropic practices have been used in ancestors.The late African grey parrot Alex, the brain, but their similarity stops there. Historian the past by authoritarian institutions or gov- famous vervet monkeys, and the chimpanzees Daniel Lord Smail takes on the full chronol- ernments to control people. Smail suggests that Kanzi, Austin and Sherman are all here. So are ogy of the human past and condenses it into a they arose slowly during the later Palaeolithic, a host of anonymous animals, such as bright seamless narrative; James R. Hurford, a linguist, accelerated in the Neolithic, and soared during piglets that back out of the ‘wrong’ arms of T- delves even further into the past to explore the the past few centuries; he attributes our enjoy- mazes, apparently to avoid giving incorrect evolutionary foundations of language. ment of them to the fact that we are social crea- responses. Do animals know what they know Smail believes that history should bring tures who have always assessed our standing in — that is, do they have self-awareness? Hurford prehistory into its fold, and focuses on biol- groups through chemical cues. Perhaps so. shows that the seeds are there, and were prob- ogy, brain and behaviour in his endeavour. He Although this is an enjoyable and creative ably present in our ancestors, providing fodder first describes how the discovery and implica- book, it is not quite what I expected. There for natural selection. tions of deep time by geologists, biologists and are no endocasts or sulcal patterns here, no Likewise, the capacity to realize something naturalists in the mid-nineteenth century were Brodmann’s area 10, or debates on brain size about objects (even that they are no longer the undoing of the sacred idea that human- versus cortical reorganization (although Hob- present) is common to many animals and kind began relatively recently in the Garden bits receive a brief mention). Notwithstanding may have been a prerequisite for the emer- of Eden. Historians then shifted from a sacred these omissions, its fla- gence of the linguistic feature of ‘displaced to a secular beginning — the rise of civiliza- vour and neuro- reference’. Hurford argues that the abil- tion in Mesopotamia. Thus, laments Smail, the historical ity of many animals to infer animacy NATURE Palaeolithic continued to receive short shrift in objects (related to detecting bio- and still needed to be ‘histori- logical motion) was necessary for cized’. After all, humans who our ancestors to evolve ‘theory did not keep records still had of mind’. Other comparative a past. He has a point. discussions include the evo- Smail examines the rup- lution of episodic memory, ture that continues to separate which Hurford thinks prehistory from recorded history, emerged more recently together with the historiographi- than semantic memory, cal, epistemological and theoretical and the accurate per- obstacles that have kept them apart. ception of a number He explores the importance of biol- of objects without ogy in shaping cultural evolution, counting (usually offering an interesting take on the around four), and the nature/nurture dichotomy with his relationship of such suggestion that lamarckian mecha- abilities to the evolu- nisms displaced darwinian ones tion of specific aspects of when human culture started to language. develop. Hurford locates an evolu- Smail’s discussion of the brain is tionary starting point for lan- framed within a critique of evo- guage in early hominins in the simple lutionary psychology, which two-way communications from which considers that cognitive mod- grammatical complexity and descriptive power ules have been handed down, eventually grew. He discusses physical and more-or-less unchanged social environments of apes to locate possible from the deep evolutionary precursors of group-wide reciprocal commu- past — “Stone Age brains nications. He rejects male–female relationships acting clumsily in modern and parent–offspring interactions because they environments.” Cognition has been overem- are too asymmetrical, but views play behaviour phasized, he believes, to the detriment of the Cranium of Tournaï, the earliest known hominid. among juveniles as more symmetrical and drives, motivations, emotions, moods and other Will we ever know what went on inside it? therefore a likely precursor. The literature on

31 BOOKS & ARTS NATURE|Vol 450|1 November 2007 mother–infant interactions, however, indicates that these are not asymmetrical and may have Space and time gift-wrapped been a focus of intense natural selection. The discussions in The Origins of Meaning of ritualization, emulation, imitation, learning Very Special Relativity: An illustrated taken for granted, and he does allow a dp/dt and ‘machiavellian intelligence’ are insightful. Guide to slip in when discussing momentum and So is the review of communications that include by Sander Bais forces. He manages to navigate all the way gaze-following, attention-seeking behaviour, Harvard University Press: 2007. 144 pp. to E=mc2 and to give us a taste of Einstein’s pointing, begging and alarm calls in non- $20.95, £13.95 even more miraculous work of the follow- human primates and/or young humans, and ing decade, his general relativity theory of their possible implications for the evolution of Andrew Jaffe gravitation. referential language. After considering niche Sander Bais’s Very Special Relativity is a brief Very Special Relativity is aimed at an under- construction, kin and sexual selection, and overview of Albert Einstein’s 1905 theory of served market: keen high-school students reciprocal altruism, Hurford concludes that space and time, an esoteric topic that one will welcome it because it extends beyond communicative cooperation and trust may have would presume to be directed at a narrow qualitative discussion of ‘modern’ physics and been the most crucial factors in the emergence audience. But this book would not be out of popular-science books. With its brainteaser of language. place on a coffee table, with its handsome problems, it should also work as an under- There are some titillating nuggets in this design, thick, coloured papers and imagina- graduate introductory textbook. Readers who book, such as a discussion of how the FOXP2 tive graphics that match the high standard of haven’t exercised their mathematical and geo- gene was mistakenly accepted as the ‘magic its content. We expect art books, not science metric muscle since they were in school might bullet’ responsible for language evolution. Even texts, on our coffee tables, assuming that in find it tough going. better is the extent to which academics from science it is the ideas that matter, not the vis- It is rare for science books to rate as objects different countries use language competitively ual presentation. in their own right, but Very Special Relativity is to show off — guess where Americans rank? Here, the elegant illustrations help Bais lead a lovely little object. You could easily imagine Has Hurford achieved his goal of describ- the reader from Einstein’s postulates through a web-based version of it, with a bit of anima- ing the evolutionary foundations of language? the ideas of simultaneity, inertial frames, time tion to serve its pedagogical needs. Still, there Yes, elegantly and in accomplished detail that dilation and relativistic energy and momen- is some quality about the hard covers and should be accessible to all those specialists tum, eschewing the usual admonitions against high resolution that even my 26-inch screen the book targets. I look forward to finding equations. The author’s clever idea of pairing wouldn’t be able to capture. No longer is there out what he thinks happened next in the sec- every page of text with a space–time diagram an excuse for physics textbooks to be expen- ond volume. ■ (a graphical tool actually used by relativists) sive, boring, thick or stuffed with equations in Dean Falk is in the Department of Anthropology, to illustrate the concepts and mathemat- order to qualify as good teaching material. ■ Florida State University, Tallahassee, Florida ics suits the geometrical basis of its subject Andrew Jaffe is professor of astrophysics 32306-7772, USA. She is the author of perfectly. It allows Bais to stop just short of and cosmology in the Astrophysics Group, Braindance: New Discoveries about Human Origins using calculus — although the definitions Blackett Laboratory, Imperial College London, and Brain Evolution. of things such as ‘slope’ and ‘tangent’ are London SW7 2AZ, UK.

PAINTING Hidden depths spotted

Emiliano Feresin and iron — a typical signature of lacquers — Nuclear physicists have revealed that the in tiny, uneven spots over the red cloak of the work of Sicilian artist Antonello da Messina unknown subject. Although such glazes were (1430–79) may have been ahead of its time. already in use in the fifteenth century, they He was among the first, they suggest, to were normally applied with a brush over an subtly refine the shading in his paintings by entire surface. The scan reveals a weave-like spotting them with lacquer. When applied to imprint across the red cloak, suggesting to the particular areas of a painting, this glaze, made restorers that here the shiny substance was from red pigment mixed with oil, enhances the dabbed on with a cloth. impression of depth. Later, similar effects were created by great Pier Andrea Mandò and his colleagues masters such as Leonardo da Vinci (1452– at the Italian National Institute of Nuclear 1519), who used his finger, and Rembrandt Physics’ Labec laboratory in Florence took (1606–69), who used the end of his brush. advantage of the availability of Antonello’s But if Mandò and his colleagues are correct, it Portrait of a Man (1476) during its restoration was Antonello — best known for introducing this summer. They had already developed certain techniques of Flemish masters into and used non-destructive PIXE (for ‘particle- Italy — who pioneered the effect. ■ induced X-ray emission’) scans to reconstruct Emiliano Feresin is an intern in Nature’s

the spatial distribution and concentration of Munich office. OF TURIN MUSEUM FOUNDATION) TURIN (COURTESY CIVIC MUS. ANCIENT ART, chemical elements on the surface of some types of artistic work, such as gold laces The restored Portrait of a Man, pictured and embroideries. They wanted to try the here, can be viewed at the Civic Museum technique for the first time on a painting. of Ancient Art in Palazzo Madama, Turin: The physicists identified traces of aluminium www.palazzomadamatorino.it.