Ian Tattersall

Masters of the Planet provides an excellent overview of the current state of our knowledge of the evolution of humans and other hominids. Back in the 1960s, hominid evolution could still be viewed as unilinear and progressive, leading towards Homo sapiens along a single axis of evolutionary change. As outlined in this book, an impressive array of fossil finds and sophisticated technical analyses have yielded a very different picture, one in which diverse lineages of hominids existed show more simultaneously and interacted. The profusion of paleontological discoveries has buried the traditional creationist myth of "missing links." Indeed, the sheer number of fossils and structurally intermediate forms has sometimes made it difficult to determine which of the many candidates is closely- related to which.

Ian Tattersall, author of Masters of the Planet, is curator emeritus at the American Museum of Natural History in New York. He brings to the issues a lifetime of expertise in hominid evolution, as well as abundant experience in writing books and articles for fellow scientists and general audiences. The book is organized historically, and traces the diverse and complicated history of hominids over the past 7-8 million years. Beginning with the ancient origins of the hominid lineage, it outlines the rise of bipedal apes, the variety of australopiths (including "Lucy"), life on the savannah, emergence from Africa (an event that occurred multiple times), the spread of early Homo throughout the Old World continents, the enigmatic Neandertals (distant cousins to ourselves, not ancestors – except to the degree in which we interbred), and ultimately, the arrival of modern H. sapiens. The book does not focus entirely on skeletal features. Rather, such aspects as development of social behavior, running ability, loss of body hair, diet, use of fire, and cooking all get their due. Tattersall's account leads towards recognition of the distinctiveness of our species, as manifested by language as well as symbolic behavior, features that he considers to be responsible for our species' success.

In tracing hominid diversity and evolutionary history, Tattersall draws on contemporary technological analyses to reveal details that would have been unimaginable a decade or so ago. Thus, readers may be surprised to find what isotope analyses have revealed about diets of early hominids, and what genetic analyses have shown about skin and hair color in Neandertals. Tattersall does not shy from recognizing unresolved issues and persistent controversies. He fairly presents alternative viewpoints, and freely acknowledges areas where a scarcity of evidence has rendered divergent interpretations viable.

As one who has read many books on hominid evolution, I found Tattersall's work to be interesting and informative. My copy is now replete with penciled comments and bent- down page corners to mark fascinating issues and controversial matters. While the book's dealings with uniqueness of our own species' overlaps that of Brian Fagan's recent Cro-Magnon, I found Tattersall's account preferable in some respects. The latter recognizes the emergence of artistic expression (starting at least 70,000 years ago) as a worldwide phenomenon rather than one local to Europe and Asia, in accord with its status as a species characteristic.

Notwithstanding my high regard for this book, it is not free of error. The hyoid apparatus is not a "bony portion of the Adam's apple" (as stated on page 36). Rather, the hyoid consists of thin cartilages that support the tongue and its musculature, while the so-called Adam's apple is the larynx. (How the two could be confused by a paleo-anatomist is most puzzling). "Exaptation" is wrongly presented as a non- adaptationist mechanism (pages 44, 68, and 210), in which features arise by chance and only later evolve to take on a function. Evolutionary biologists will recognize this characterization as mistaken. In exaptation, features that are evolutionary adapted to serve one function are transformed through natural selection to serve some new function (as outlined in Gould and Vrba's original 1982 paper in Paleobiology and throughout the modern literature). As another example, the author suggests that "members of the genus Homo have been consistently predisposed in the same way towards brain size increase"(page 132) since brain enlargement occurred in three separate lineages. However, one need not infer any special mechanism or attribute unique to our genus. A trend towards brain enlargement has occurred independently in many mammalian lineages, as well as in numerous linages of birds and cartilaginous fishes, and even among molluscs and arthropods. In this respect, hominids appear (with aquatic mammals) as an extreme example of a widespread evolutionary trend.

Some interpretations in the book are quite speculative, leading to weak inferences. For example, discovery of one toothless male skull (the Dmanisi specimen) is taken as evidence for long- term compassionate behavior among Homo erectus era hominids, on the grounds that the individual would not have been able to chew his own food. (Page 124: "…it seems entirely reasonable to conclude that the Dmanisi hominids had the cognitive reserves to express their fellow- feeling in the form of material support"). In view of the profusion of other interpretations, the inference is unnecessarily speculative. One might also question the book's central claim that emergence of artistic expression in our species paralleled the development of a unique form of psychology, as manifested in our capacity for symbolic thought. Fossils reveal little about psychology, and how early symbolic thought arose arguably is entirely a matter of speculation – cave art and jewelry notwithstanding.

Such issues do not detract from a work that, on the whole, is one of the best modern accounts available; indeed, some of the above manifests the fascinating and thought – provoking nature of this book. Overall, I would strongly recommend Masters of the Planet as an interesting and informative account of the diversity and evolutionary history of the bipedal apes and we their peculiar descendants. show less

This excellent book gives a very useful overview of human evolution, including:

(1) The methods used by scientists try to find out the facts. (Some of this part of the book gets rather technical.)
(2) The history of the scientific search for knowledge of human origins.
(3) The current state of knowledge, and the current debates and controversies. (Controversies based on conflicting interpretations of the genetic and fossil evidence.)

In this review, I am just going to focus on Tattersall’s show more views on two major current debates about the origins of modern Homo sapiens.

Firstly, there is the debate about where H. sapiens originated. To follow this debate, it is necessary to know that there are two types of evolution. Firstly, there is anagenesis. This is where there are evolutionary changes WITHIN a species over time. For example, if the environment (physical, biological or climatic) of an entire species gradually changes, then natural selection could lead to the whole species itself gradually changing.

The other type of evolution is cladogenesis. This is where a new species branches off from an existing one. This speciation process usually takes place when a peripheral population of a species becomes geographically isolated. When this happens, this isolated population can evolve relatively rapidly (in geological terms) into a new species. (This view is compatible with Gould and Eldredge’s theory of “Punctuated Equilibrium”.)

There is a currently influential theory which says that modern H. sapiens did not originate in one place. This theory is called African Multiregionalism or the Pan-African Network model. It says that there were semi-separated populations of a pre-sapiens species (probably Homo heidelbergensis) spread right across Africa. Each population developed slightly different features, but they occasionally interbred. When this happened it led to modern H. sapiens, which is therefore a composite, rather than a result of speciation in one place. This means, in effect, that H. sapiens appeared as a result of anagenesis, not cladogenesis, and that there is really no distinct boundary between H. sapiens and H. heidelbergensis. (Taken to its logical conclusion, it seems to me that it could end up with seeing all the species in the Homo genus as just one big species developing via anagenesis.)

Although Tattersall does not specifically mention this “Network” theory in this particular book, he certainly puts forward a view which totally contradicts the theory. Tattersall opts instead for the importance of cladogenesis, with H. sapiens first appearing in an isolated population and then spreading across Africa to replace other Homo species – quite possibly with some interbreeding with them, as there was later with Neanderthals after H. sapiens had spread out of Africa, because speciation is a process and it takes time for total reproductive isolation to develop. Personally, I’m only an interested amateur, but I find Tattersall’s view more convincing than the Network/African Multiregionalism model.

The second area of debate which Tattersall is involved in relates to when language and modern human consciousness first developed. Some scientists have in the past claimed that in the history of our own species (Homo sapiens) there was a “creative explosion” in Europe about 40,000 years ago (with the appearance of cave art etc), long after the appearance of the species itself 200,000 or 300,000 years ago. They claimed that this “Great Leap Forward” was caused by some biological change to the brain, possibly linked to the development of language. In his best-selling book “Sapiens” (which is not taken seriously by the scientific community because of its speculative nature), Harari has put forward a similar idea of a “Tree of Knowledge” genetic mutation 70,000 years ago.

But this idea of some (invisible and unprovable!) biological change to the brain either 40,000 or 70,000 years ago has been shot down in recent years by the discovery of evidence for art and sophisticated tools dating from much earlier than the time that the “Great Leap Forward” is supposed to have happened.

Back to Tattersall. Like the advocates of the “Great Leap Forward”, he also believes that modern symbolic consciousness appeared long after Homo sapiens first evolved. But he argues that the modern brain, with all its full, modern potential, appeared with the first H. sapiens, but that this potential was not fulfilled until much later when H. sapiens started to use symbols and fully-developed language for social/cultural reasons.

It seems to me that there are problems with Tattersall’s view on this. Firstly, there is more and more evidence of art being found that dates back to well before 100,000 years ago. (Tattersall says that this is not proper, symbolic art.) Secondly, it could be that a lot of symbolic art was created very early on, but this has either not survived or not been discovered yet. (As the archaeologists say, “Absence of evidence is not evidence of absence.”) Thirdly, there seems to be some evidence that language goes back much further than Tattersall suggests, even possibly to Neanderthals and H. heidelbergensis). (Though, again, Tattersall says that this was not fully-developed modern language.)

We certainly need to remember that, even if there was a “creative explosion”, it should not be assumed that behavioural change must be determined by biological change. Why does cultural change have to imply a change to the brain? It is more likely that the brain had become “modern” when Homo sapiens first evolved, and that any later cultural change took place for non-biological reasons. After all, the development of farming 12,000 years ago, of cities and writing 5,000 years ago, and of industry 200 years ago were also “Great Leaps Forward”, but no one believes that these were the result of genetic changes to the human brain.

Apologies for this review being rather long. But I find these two debates fascinating. Anyway, I recommend this book. show less

In his new book The Strange Case of the Rickety Cossack, human paleoanthropologist Ian Tattersall argues that a long tradition of "human exceptionalism" in paleoanthropology has distorted the picture of human evolution. Drawing partly on his own career--from young scientist in awe of his elders to crotchety elder statesman--Tattersall offers an idiosyncratic look at the competitive world of paleoanthropology, beginning with Charles Darwin 150 years ago, and continuing through the Leakey show more dynasty in Africa, and concluding with the latest astonishing findings in the Caucasus.The book's title refers to the 1856 discovery of a clearly very old skull cap in Germany's Neander Valley. The possessor had a brain as large as a modern human, but a heavy low braincase with a prominent brow ridge. Scientists tried hard to explain away the inconvenient possibility that this was not actually our direct relative. One extreme interpretation suggested that the preserved leg bones were curved by both rickets, and by a life on horseback. The pain of the unfortunate individual's affliction had caused him to chronically furrow his brow in agony, leading to the excessive development of bone above the eye sockets. The subsequent history of human evolutionary studies is full of similarly fanciful interpretations. With tact and humor, Tattersall concludes that we are not the perfected products of natural processes, but instead the result of substantial doses of random happenstance. show less

Having read and enjoyed Ian Tattersall's earlier work The Fossil Trail for a college class several years ago, I was delighted to see his latest, Masters of the Planet: The Search for Our Human Origins (Palgrave Macmillan, 2012). The two works cover much the same ground; Tattersall offers an overview of recent research into the evolutionary history of hominid species, highlighting the latest finds and discoveries of fossilized hominid remains, tools, &c.

A couple things that struck me about show more this book: first, how much of the hominid record is still uncertain at best. Tattersall quite frequently has to add qualifiers to his statements since they're based on the very small bits of data that have been discovered and studied so far. Along the same lines, he pillows many assertions with the note that not all scholars agree with this interpretation or that. It was refreshing, actually, to see how much of all this isn't settled science, and how the discovery of a single fossil might put a whole new light on things (as the discovery of Homo floresiensis a few years ago did).

I'm glad I read this book fairly close on the heels of E.O. Wilson's The Social Conquest of Earth. While Tattersall doesn't get into the evolution of social behavior, his other conclusions generally seem to jive with Wilson's fairly closely, but Tattersall is able to explore at greater depth some of the specific early hominid fossil sites, and to offer additional anatomic and taxonomic details about the species he discusses. I'd actually like to see a conversation between Tattersall and Wilson about whether they see things differently ... wouldn't that be something?

Packed with detail, but quite readable, and supplemented with a long list of sources should you find yourself interested in a particular topic. show less