The Journey of Man: A Genetic Odyssey

I saw Spencer Wells on Book TV talking about his book and TV special, so when I found the book in paperback I snapped it up. And I am very happy I did. I knew a lot of the history he went over to explain why and how the Y-chromosome could be used to trace human evolution and how humans spread over the world. The reason I enjoyed it so much is that I have many of the books he used as sources and it allowed me to read without those full halts that sometimes happens when you hide an idea or fact you never heard of before. But even people who have no knowledge how DNA works or have no idea how our prehistoric forefathers lived will find the book interesting and easy to absorb. The Y-chromosome not only helps us trace the male DNA back to Africa, it is also shown to help answer once and all questions about language families and even how the knowledge of farming spread. The language used in the book is easy to understand and Mr. Wells knows how to explain even complex issues with humor and clarity. Some information about Homo erectus/ergaster in Asia MIGHT be out-dated with the discovery of Homo floresiensis (Hobbits), but the data about Homo sapiens is still sound.

I first heard the author speak at the Smithsonian on the genetic odyssey of mankind, in the best talk I've ever heard, and I go to many talks every year. Then I read the book and watched the two-hour PBS presentation by the same title. The author does a great service by summarizing much scholarship in genetics, archaeology, and linguistics, to paint a family portrait of the human race based on analysis of the Y chromosomes of peoples all over the world--an intriguing story, well told and accessible to the non-specialist, if not the general reader with a minimal background in college biology and biochemistry. The author's sense of humor adds to the delightful tale of mankind's journey. This is the most interesting book I've read since Jared Diamond's best seller, "Guns, Germs, and Steel," and encourages me to read more books in this area. Dr. Wells, who refers to himself in the PBS show as a "lab rat," has done a great service both to his field and to the public by sharing the results of detailed and laborious scientific research with the larger human race whose ancestors are the subject of this fascinating history.

A few years ago a furor arose over the announcement that a calculation of mitochondrial DNA mutation rate formulated an "African Eve". Since then other genetic ancestral studies have been undertaken. Most notable of these was the determination that Neanderthal was not a direct ancestor of modern humans. Spencer Wells provides an enthralling overview of the research tracking changes in the Y [male] chromosome. The studies verify again that our origins are African. Somewhere, around 60 000 years ago, lived one man, a flesh and blood individual, from whom we've all descended. His progeny, in an amazingly short span, scattered around the globe. The scattering isn't news, but the verification of the paths and chronology is lucid and vividly outlined in this book. The key to the tracking, as Wells makes abundantly clear, are various polymorphisms [changes] in the Y chromosome. These mutations are reflected in today's populations and the rate of their diversity indicates the approximate age of the various regional groups. These changes, nearly all prefixed "M" [male?] are used as ingredients in recipes Wells offers as illustrative metaphor. It's a clever ploy, so long as you remember ingredients may only be added, never removed nor replaced. That's how genetics works, he reminds us. He portrays the build-up of recipe ingredients with maps and diagrams. The diagrams are almost redundant as the clarity of his prose enables you to envision them.Following the paths of migration, Wells shows how some archaeological finds offer support for the patterns he sees. Fossils are rare, elusive and sometimes misunderstood. Genetics, buried deep in our cells, are unequivocal in providing their evidence. Dating methods are briefly described and their shortcomings mercilessly paraded. Wells doesn't give the paleoanthropologists much voice. His story needs telling and the reader may go elsewhere for countering information. Yet he acknowledges the importance of confirming information from various digs around the world.Wells firmly addresses a great anomaly - if modern humans arose from the evolutionary bouillabaisse about 60 millennia ago, how did the Aborigines arrive in Australia at nearly the same time? His answer is that the track followed shore routes, not inland ones. Hunter-gatherer groups, subject to the whims of climate, food resources and population pressure took the softest trail. Africa to Australia during ice ages was a gentle, if lengthy, stroll. Nit-picking department: Wells' opening gun is turned on the racial "expert" Carleton Coon, who asserted the human races each followed a separate evolutionary path. Coon has been refuted in so many ways by so many researchers, Wells' effort seems superfluous. There are more competent scientists adhering to the "Multiregional" thesis. Some of these researchers might have been given a small voice in an annotated bibliography. While Wells offers a reading list for each chapter, a full bibli

This book will blow you away. In clear, easy-to-follow language, with helpful analogies, Wells describes a scientific and geographical journey wherein, by means of DNA analysis, he and his fellow scientists tracked the contemporary "Y" chromosome from two common ancestors in Africa to the DNA of every living human being. Unbelievably, there really was one "Adam" and one "Eve" -- although they lived more than 100,000 years apart -- whose descendants left Africa about 40,000 years ago and, over 2000 subsequent generations, were the origin of us all. The understanding that we are all related -- cousins many thousands of times removed, if you will -- may not have any immediate effect on politics and social relations, but it does put our human conflicts into a different context, as well as blast away most genetically-based theories of race. Although cultures may differ in many respects, and human beings may subscribe to different value and belief systems, we really are, genetically, one human family. I read this book cover-to-cover in one day, and found it fascinating, astonishing and inspiring. Kudos to Wells and his crew. Also, those of you who have kids who may be too young to follow the science in this book should try the video.

Archeologists dig all over the earth to find the history of people who existed too early to leave a written history. There is a new sort of archeology, however, that is changing our long-range view of human pre-history. Scientists are digging into cells, into the genes that everyone knows make us what we are. The details from this new research have given revolutionary insight into where humans came from, how they spread, and the origin and superficiality of races. In _The Journey of Man_ (Princeton University Press), Spencer Wells, a population geneticist, has written a wonderfully clear book of origins, drawing upon not just genes but history, geography, archeology, and linguistics.In part, the book is a summary of refutations against the ideas of anthropologists who maintained that different races were subspecies that arose in different regions at different times. No such hypotheses could be tested in the time they were issued, and now they can. DNA in the cells from mitochondria, and the DNA in the male Y chromosome do not shuffle the way ordinary chromosomes do, and thus are very stable from one generation to the next. Mutations happen, and accumulate, and may be used to see how closely related humans from different regions of the world are. The genetic results of both mitochondrial and Y chromosome research confirm each other, and are unambiguous. We are all out of Africa. We stayed in Africa as humans for generations, and almost all the genetic variation we were going to get was within us at that time. Then around 40,000 years ago, propelled perhaps because of weather changes, we started our travels. _Journey_ has good diagrams, but a map showing the flow of different Y chromosome linkages around the world can be regarded with awe, for the history it shows and for the scientific advances that have made such a diagram possible. Our current way of living has wrought changes in plenty of the subjects in this book. The trail of languages in many ways parallels the trail of genes around the world, but as we develop a global culture, languages are dying out at a faster rate than ever before. Also, there is greater mixing of genes from different cultures now that easy travel makes possible the meeting of members of tribes that would never have met before. It could be that we have passed the heyday for the sort of research reported here, as populations swap genes in unprecedented ways. Nonetheless, Wells's book is full of enthusiasm for basic research, and the results described here are fascinating. We can look back at our origins with new respect for how long and how strange a journey it has been, and with the increasing realization that that our one species has one shared history.