- Email: [email protected]
The history of humanity in our genes
CULTURELAB
Life’s mysteries Why did we evolve to have religion and breasts? Perhaps we will never know Homo Mysterious: Evolutionary puzzles of human nature by David P. Barash, Oxford University Press, £18.99/$27.95 Reviewed by Kate Douglas
Herwig Prammer/Reuters
THERE are some thorny mysteries in the evolution of female sexuality. Is there a purpose to the female orgasm? What about menopause, menstruation and prominent breasts? Evolutionary psychologist David Barash jumps bravely into exploring these and other conundrums of human evolution in his new book, Homo Mysterious. In searching for the “why” behind these unexplained oddities, Barash provides a wideranging survey of the territory, and he is at his most entertaining when describing his own ideas. His handicap theory of female breasts is rather clever. He suggests that, like the peacock’s tail, a permanently voluptuous
48 | NewScientist | 7 July 2012
dowdy sex when sexual selection usually produces showy males, and why they tend not to live as long as women. There is also a very cogent chapter on homosexuality – although while Barash notes recent evidence pointing to its having different genetic underpinnings in men and women, he fails to consider that homosexuality might therefore have separate adaptive rationales in the two sexes. Barash also takes on the weighty topics of religion, art and human intelligence. There is plenty here to inform and entertain, but he doesn’t always marshal his eclectic material effectively. The chapters on religion make particularly frustrating reading, often just
bosom might be a woman’s way of signalling her fitness by showing that she can thrive despite depositing so much valuable fat into cumbersome and mostly decorative appendages of a sort found nowhere else in nature. Equally appealing is his favoured explanation for concealed ovulation – the fact that women’s increased fertility is not broadcast. Barash suggests that once females became intelligent enough to link sex with babies – and babies with hard work – they “Why are men the dowdy sex when sexual selection could have tried to limit their birth rates. Those whose cycle was usually produces such showy males?” least discernible to themselves would have been least successful at avoiding pregnancy, so women noodling around the subject instead of asking why this with concealed ovulation gradually became more common. particular primate and no other evolved strong tendencies to But why are evolutionary spiritual thinking. No distinction mysteries of female sexuality far is drawn between traditional, more numerous and prominent small-scale religions and today’s than their male counterparts? predominant world religions. And Barash remains disappointingly Barash leaves a rather grudging silent on this, although he does scrutinise some manly mysteries, explanation of evolutionary group selection until last, so such as why men are the more that readers are not provided with a sufficient theoretical framework in which to assess some frankly iffy ideas from Freud and the like. No mysteries were solved in the writing of this book. Instead, Barash argues that wisdom comes from learning about what we don’t know. I agree, but I am not convinced, as he is, that these evolutionary puzzles are ultimately solvable. We can use new insights from genetics, psychology, palaeoanthropology and archaeology to hone our ideas, but when it comes to human evolution there will always be an element of mystery. n
Our genetic quirks The Violinist’s Thumb by Sam Kean, Doubleday/Little, Brown, £20/$25.99 Reviewed by Chris Gunter
THE waitress stopped as she passed my table. “Is that a mystery you’re reading? Cover looks like it.” “No,” I answered. “It’s a fast-paced, breezy romp through history using DNA as a unifying theme – it’s nerd-vana.” In truth, it’s a wonder that I broke away for long enough to converse at all, given the wealth of engaging information contained in every paragraph of this book. In it, science writer Sam Kean sets out to explain many human phenomena in the light of DNA, speeding from personality quirks of early geneticists to evidence for interbreeding between Neanderthals and humans. The book’s title refers to Kean’s retrospective diagnoses of medical conditions in historical figures, in this case attributing Ehlers-Danlos syndrome to Niccolò Paganini, the violinist. One symptom is doublejointedness, which would help explain his virtuosic abilities. There are a few problems. When explaining the transmission of leukaemia between a woman and her fetus, Kean asserts that maternal-fetal microchimerism does not happen. In fact, almost all of us have some of our mother’s – and, if you are a mother, your child’s – cells within us. Kean’s example is just a tragic demonstration of the phenomenon, as cancer cells are among those that cross the placental barrier. Despite some slips like this, Kean’s book is engaging. I couldn’t help scribbling on pages, with comments equally split between “ooh, interesting!” and “double check this”. Either way, The Violinist’s Thumb kept me hooked. n
Life’s mysteries Why did we evolve to have religion and breasts? Perhaps we will never know Homo Mysterious: Evolutionary puzzles of human nature by David P. Barash, Oxford University Press, £18.99/$27.95 Reviewed by Kate Douglas
Herwig Prammer/Reuters
THERE are some thorny mysteries in the evolution of female sexuality. Is there a purpose to the female orgasm? What about menopause, menstruation and prominent breasts? Evolutionary psychologist David Barash jumps bravely into exploring these and other conundrums of human evolution in his new book, Homo Mysterious. In searching for the “why” behind these unexplained oddities, Barash provides a wideranging survey of the territory, and he is at his most entertaining when describing his own ideas. His handicap theory of female breasts is rather clever. He suggests that, like the peacock’s tail, a permanently voluptuous
48 | NewScientist | 7 July 2012
dowdy sex when sexual selection usually produces showy males, and why they tend not to live as long as women. There is also a very cogent chapter on homosexuality – although while Barash notes recent evidence pointing to its having different genetic underpinnings in men and women, he fails to consider that homosexuality might therefore have separate adaptive rationales in the two sexes. Barash also takes on the weighty topics of religion, art and human intelligence. There is plenty here to inform and entertain, but he doesn’t always marshal his eclectic material effectively. The chapters on religion make particularly frustrating reading, often just
bosom might be a woman’s way of signalling her fitness by showing that she can thrive despite depositing so much valuable fat into cumbersome and mostly decorative appendages of a sort found nowhere else in nature. Equally appealing is his favoured explanation for concealed ovulation – the fact that women’s increased fertility is not broadcast. Barash suggests that once females became intelligent enough to link sex with babies – and babies with hard work – they “Why are men the dowdy sex when sexual selection could have tried to limit their birth rates. Those whose cycle was usually produces such showy males?” least discernible to themselves would have been least successful at avoiding pregnancy, so women noodling around the subject instead of asking why this with concealed ovulation gradually became more common. particular primate and no other evolved strong tendencies to But why are evolutionary spiritual thinking. No distinction mysteries of female sexuality far is drawn between traditional, more numerous and prominent small-scale religions and today’s than their male counterparts? predominant world religions. And Barash remains disappointingly Barash leaves a rather grudging silent on this, although he does scrutinise some manly mysteries, explanation of evolutionary group selection until last, so such as why men are the more that readers are not provided with a sufficient theoretical framework in which to assess some frankly iffy ideas from Freud and the like. No mysteries were solved in the writing of this book. Instead, Barash argues that wisdom comes from learning about what we don’t know. I agree, but I am not convinced, as he is, that these evolutionary puzzles are ultimately solvable. We can use new insights from genetics, psychology, palaeoanthropology and archaeology to hone our ideas, but when it comes to human evolution there will always be an element of mystery. n
Our genetic quirks The Violinist’s Thumb by Sam Kean, Doubleday/Little, Brown, £20/$25.99 Reviewed by Chris Gunter
THE waitress stopped as she passed my table. “Is that a mystery you’re reading? Cover looks like it.” “No,” I answered. “It’s a fast-paced, breezy romp through history using DNA as a unifying theme – it’s nerd-vana.” In truth, it’s a wonder that I broke away for long enough to converse at all, given the wealth of engaging information contained in every paragraph of this book. In it, science writer Sam Kean sets out to explain many human phenomena in the light of DNA, speeding from personality quirks of early geneticists to evidence for interbreeding between Neanderthals and humans. The book’s title refers to Kean’s retrospective diagnoses of medical conditions in historical figures, in this case attributing Ehlers-Danlos syndrome to Niccolò Paganini, the violinist. One symptom is doublejointedness, which would help explain his virtuosic abilities. There are a few problems. When explaining the transmission of leukaemia between a woman and her fetus, Kean asserts that maternal-fetal microchimerism does not happen. In fact, almost all of us have some of our mother’s – and, if you are a mother, your child’s – cells within us. Kean’s example is just a tragic demonstration of the phenomenon, as cancer cells are among those that cross the placental barrier. Despite some slips like this, Kean’s book is engaging. I couldn’t help scribbling on pages, with comments equally split between “ooh, interesting!” and “double check this”. Either way, The Violinist’s Thumb kept me hooked. n