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century biologists Thomas H. Huxley, ultimately civilization. Obviously, for The heroic art Charles Darwin, Ernst Haeckel, Arthur Darwin, principles of natural selection Keith and Grafton Elliot Smith in order were the operative mechanism (the of storytelling to identify nine functions that she be­ hero's helper or donor) during this jour­ lieves characterize all narratives of hu­ ney. For Keith, on the other hand, Glenn C. Conroy man evolution: (1) the initial condition orthograde posture evolved while ances­ in which the evolutionary hero is found tral humans were still in trees and this, Narratives of Human Evolution. By Misia (in all narratives of human evolution this rather than terrestriality per se, was the Landau. Yale University Press: 1991. setting is usually in a relatively carefree initial point of departure for human Pp . 202. $25, £14. arboreal environment); (2) the hero is evolution. As an anatomist fascinated introduced as being somehow slightly with the newly discovered role of hor­ SOME people get no respect. Thomas 'different' from other nonhuman pri­ mones in growth and development, Macaulay once said that the more he mates lurking in the vicinity; (3) the hero Keith subscribed to the orthogenetic read Socrates, the less he wondered why has to leave home (the change of situa­ view that "the machinery of evolution they poisoned him, and Thomas Jeffer­ tion in being dislodged from his arboreal will be found inside the factory of the son was no less charitable to Plato when home); ( 4) the hero departs to begin a womb, rather than in the mechanism of he remarked that the only thing remain­ new journey or adventure (for example, natural selection". (Keith was an in­ ing after one took away his "sophisms, life as a terrestrial biped); (5) the hero is fluential champion of the authenticity of futilities and incomprehensibilities" was tested (by predators, climate, other the Piltdown Man and Galley Hill, and a

2 3 4 5 6 7 8 9 initial situation hero change departure test donor transformation test again triumph

arboreality terrestriality bipedalism encephal1zation civilization The sequence of events in Darwin's account of human evolution. "his foggy mind". Fossil hunters, too, closely related species and so on); (6) a defamer of the Taung Child - one have been held in similar contempt by donor or helper appears that enables the winces at how dreadful so many of his their detractors, often molecular biolo­ hero successfully to fend off the chal­ judgements were about the fossil re­ gists and cladists, who sometimes regard lenges found on the journey, thus be­ cord.) Both Darwin and Keith at least the literary byproduct of their sweat, coming the main explanatory force for had a podiatristic view of human evolu­ blood and tears (to coin a phrase) as evolutionary change in the story (such as tion, believing that human evolution little more than the art of storytelling. natural selection, orthogenesis, neo­ commenced feet-first. Elliot Smith, as In Narratives of Human Evolution, the lamarckism); (7) gifts are bestowed on befitted a neuroanatomist, saw human palaeoanthropologist-cum-literary-critic the hero (for instance, increasing brain evolution from a head-first perspective, Misia Landau, rescues the art of anthro­ size, intelligence, language, tools, mor­ that is, with increasing encephalization pological storytelling by analysing just als) and he is duly transformed; (8) the being the prime mover in human evolu­ how complex these stories really are and hero is tested once again; and (9) the tion, occuring long before ancestral what their underlying structures reveal hero finally triumphs, that is, civilization humans hit the ground. Like Keith, he about the basic evolutionary and social (usually European) is attained. was also an orthogenist. But as Landau principles of their authors (what she The most enlightening aspect of such recognizes, Elliot Smith's donor lies refers to as "this altar housing a deep an analysis is the recognition that these buried in the hidden recesses of the diversity of faiths"). nine actions, or functions, of the drama­ brain (Elliot Smith's Tomb) whereas Landau considers any account of a tis personae can assume very different Keith's donor resides within the embryo sequence of events that manifests "a meanings depending on where they (Keith's Womb). deeper kind of belonging" (such as the occur in the narrative. In other words, Landau's approach to palaeoanthro­ story of human evolution) as a form of although stories of human evolution may pology is informative and entertaining. narrative that can be studied by techni­ take similar narrative forms and all share Her analyses of the writings of Huxley, ques of literary criticism. Using methods the same time functions , their underlying Darwin, Haeckel, Keith and Elliot Smith originally developed by Vladimir Propp meanings may differ substantially de­ are incisive and provocative, and lay in Morphology of the Folktale (Univer­ pending on which function is regarded as bare the biases that each brought to their sity of Texas Press, 1928), an analysis of the prime mover in the story and which narratives. This makes it all the more Russian folktales , Landau first breaks evolutionary mechanism (the donor or unfortunate that her treatment of more down narratives of human evolution into helper) operates as the hidden agent of contemporary narratives of human their component, or functional , parts. A evolutionary change. evolution, such as those by Theodosius critical step in such an analysis is to For example, the prime mover in Dar­ Dobzhansky, Raymond Dart, J . T. dissect the tale "according to the func­ win's narrative of human evolution was Robinson , Phillip V. Tobias and Donald tions of its dramatis personae" (that is, the shift to terrestriality, that is, when Johanson, are not as fully developed as the evolutionary heroes). These func­ ancestral hominids left the relative safety one would have hoped. This is a dis­ tions then become the basic components of the trees to face life in the tall African appointment rather than a criticism. For of the tale. grass. Thus, terrestriality set off a cas­ example, Landau's seemingly hurried Using a case-study approach, Landau cade of evolutionary events that led analysis of the debate of Johanson, Tim liberally quotes from the works of the almost inexorably to the evolution of White and Bill Kimbel with Tobias over influential nineteenth- and twentieth- bipedality, tool-use, encephalization and Australopithecus africanus and A . 326 NATURE · VOL 354 · 28 NOVEMBER 1991 © 1991 Nature Publishing Group afarensis seems almost trivial in compari­ Thus, in the darwinian view, the biolo­ reasons for the diversity of the organic son to her more compelling and dramatic gically 'superior' mammals would have world, indicating that rates of speciation critical assessment of Darwin, Huxley progressively outcompeted the dinosaurs and extinction are higher in specialist and Haeckel's struggles with more through the course of the Mesozoic era, forms: the higher diversity of the tropics herculean evolutionary themes. I would until dinosaurs eventually became ex­ is largely a consequence of finer niche­ be fascinated to see Landau dissect tinct. It is now clear that this did not partitioning among more stenotopic contemporary icons of palaeoanthro­ happen - mammalian radiations had to organisms. Mass extinctions are in his pology with the same surgical blades she await the disappearance of the dinosaurs view dramatic events that extended over uses on our idols of the past. together with many contemporary ter­ millenia or longer, and are not normally Science can be conveniently divided restrial and marine organisms, a dis­ the consequence of geologically instan­ into three classes: the 'soft sciences' such appearance caused by mass extinction taneous catastrophes. as sociology and political science, the resulting from drastic environmental de­ In reviewing the possible physical 'hard sciences' such as physics and che­ terioration at the end of the Cretaceous causes of mass extinctions in the pre­ mistry and then the 'really difficult scien­ period. Any competition between the human past, neither author is dogmatic ces' such as palaeoanthropology. Narra­ dinosaurs and mammals must therefore and both freely admit to the continuing tives of Human Evolution is a literate, have been pre-emptive rather than dis­ uncertainty and dispute within the scien­ thought-provoking explication of this placive, the key requirement being to be tific community. Because Raup believes really difficult science. I would add only the first to occupy the ecological niche. that nature would have great difficulty one further thought to Landau's story. This pattern of change appears to be eliminating species over large areas, he She notes that Huxley never did bridge characteristic of the fossil record as a favours the crash of asteroids or comets that gap between the apes and humanity whole, with episodic mass extinctions into the Earth as the cause of not just with a missing link. Maybe that is be­ clearing the decks, as it were, for the mass extinction, but background extinc­ cause the missing link is man. D radiation of new organic groups. In tion as well. This is, to my mind, a truly Raup's words, extinction appears to astonishing conclusion, being based on Glenn C. Conroy is in the Department of have been more a matter of bad luck virtually no evidence apart from the Anatomy and Anthropology, Washington Uni• than bad genes, because normal darwi­ pronounced iridium anomalies and versity Medical School, St Louis, Missouri nian finely tuned adaptations would shocked quartz at the Cretaceous/ 63110, USA. often have been a poor defence against a Tertiary boundary, which is the only rare environmental catastrophe. reason why the impact story is taken These two books on extinction by seriously at all. Eldredge takes what I Theories for leading US palaeontologists are aimed at believe to be the geologically more a wide audience and demand little tech­ reasonable view, for which there is much everything nical knowledge. Both books have con­ evidence from the stratigraphic record. siderable merits but are very different in In this view, important environmental A. Hallam their treatment of the subject, reflecting changes bound up with events confined the different aptitudes and interests of to our planet are responsible for mass Extinction: Bad Genes or Bad Luck? By their authors. Raup's great strength is extinctions. He sees no need to invoke David M. Raup. Norton: 1991. Pp. 210. his skill in handling data statistically and deus ex machina of extraterrestrial $19.95. his ability to make incisive points on the events except for the Cretaceous/ The Miner's Canary: Unravelling the basis of this quantitative approach. He. Tertiary boundary extinctions; even Mysteries of Extinction. By Niles presents a penetrating discussion of ran­ here, any impact was probably no more Eldredge. Simon and Schuster: 1991. domness, based on such diverse topics as than a coup de grace to elements of an Pp. 246. $20. the 'gambler's ruin' problem and the already perturbed biosphere. skewed distributions ubiquitous in na­ Although he does not discount sea­ ALTHOUGH argument persists about the ture, and uses this to argue cogently for level change, Eldredge favours climatic extent to which Darwin was a gradualist rarity being the main factor promoting deterioration as the most important when it came to modes of speciation, extinction. He makes a pertinent com­ extinction-inducing factor. I think that with The Origin of Species being quoted parison of mass extinctions with more he overstates the case. Whereas falling like so much Holy Writ, there is no familiar natural phenomena such as ear­ temperature appears to have been room for doubt about his views on the thquakes and floods, with the events of implicated in the Cenozoic and late relative importance of biotic as opposed greatest intensity being the least fre­ Ordovician extinctions, the evidence for to physical causes in promoting extinc­ quent. His disturbingly named "kill other times ranges from poor or equivoc­ tion. "Species are produced and exter­ curve" depicts the average number of al to nonexistent. Further, there is a minated by slowly acting causes ... and species killed for a series of waiting strong correlation between marine ex­ the most important of all causes of times, and hence tells us the average tinction and global sea-level change: re­ organic change is one which is almost likelihood of a given event in a given latively sudden falls led to extensive independent of altered ... physical con­ length of time; needless to say, mass regression of epicontinental seas, and, ditions, namely the mutual relation of extinctions fall high on the curve. probably more importantly, sharp rises organism to organism - the improve­ The title of Eldredge's book refers to were associated with the spread of ment of one organism entailing the im­ the canaries used by miners as early anoxic waters. Both could have provement or the extermination of warning systems for poisonous gases. caused devastating loss of habitat area. others". This 'struggle for existence' The recent decline of migrating song­ Despite the strong evidence for these view has been accepted uncritically by birds fits the same role on a global scale, phenomena, Raup does no more than generations of evolutionary biologists, and is clearly a measure of habitat des­ mention them in passing, whereas and is well expressed in Van Valen's truction, which in his view has always Eldredge ignores them completely. In famous Red Queen hypothesis, named been the main cause of extinction. particular, these events get around the after Lewis Carroll's character who Eldredge writes as lucidly as Raup, but objection made by Raup that the pro­ found that, in her sort of country, it took his style is less dry and more eloquent, nounced regressions of the Quaternary all the running one could do to stay in and his book is richer than Raup's in period do not correlate with important the same place. biological examples. He outlines the extinction episodes, and hence the case NATURE· VOL 354 · 28 NOVEMBER 1991 327

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