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Why Sex Matters

Why Sex Matters: A Darwinian Look at Human Behavior

Copyright Date: 2015
Edition: STU - Student edition
Pages: 432
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  • Book Info
    Why Sex Matters
    Book Description:

    Why are men, like other primate males, usually the aggressors and risk takers? Why do women typically have fewer sexual partners? InWhy Sex Matters, Bobbi Low ranges from ancient Rome to modern America, from the Amazon to the Arctic, and from single-celled organisms to international politics, to show that these and many other questions about human behavior largely come down to evolution and sex. More precisely, as she shows in this uniquely comprehensive and accessible survey of behavioral and evolutionary ecology, they come down to the basic principle that all organisms evolved to maximize their reproductive success and seek resources to do so, but that sometimes cooperation and collaboration are the most effective ways to succeed.

    This newly revised edition has been thoroughly updated to include the latest research and reflect exciting changes in the field, including how our evolutionary past continues to affect our ecological present.

    eISBN: 978-1-4008-5235-2
    Subjects: Ecology & Evolutionary Biology, Psychology, Anthropology, Biological Sciences

Table of Contents

  1. 1 Introduction
    (pp. 1-13)

    “WHY CAN’T A WOMAN be more like a man?” wailed Professor Henry Higgins inMy Fair Lady, the musical derived from George Bernard Shaw’sPygmalion. Certainly in many societies, across time, there have been women who were “more like a man.” Think of Joan of Arc, who was burned at the stake (on the minor charge of wearing men’s clothing); or of George Sand, of whom Elizabeth Browning said, “You are such a large-brained woman and a large-hearted man.” Yet in part, we remember such womenbecausethey are singular, whether we envy their ability to break free or whether...

  2. 2 Racing the Red Queen: Selfish Genes and Their Strategies
    (pp. 14-27)

    ALICE HAD SOME TROUBLE following the Red Queen’s logic: that one has to run as fast as one can just to stay in place because everything else in the landscape is running as well. Biologists, however, find the image an apt one. Consider Matt Ridley’s engaging book on the origins of sexual selection, which he chose to callThe Red Queenin recognition of the problem that the sexes continually change each other’s costs and benefits. In a way, much of biology is a record of such selective arms races.¹ Ecology is rife with examples: if faster rabbits escape coyotes,...

  3. 3 The Ecology of Sex Differences
    (pp. 28-46)

    A FAVORITE CARTOON of mine shows two deer, a buck and a pretty annoyed-looking doe standing on a hillside. The buck is tilting his head, saying, “So I like rutting—so sue me.” In the genetic gambling casino, success depends not only on individual strengths and weaknesses but also on environmental conditions and whether or not there are groups to contend with. The buck, however, highlights an influence on all sexual species. From fish to flying squirrels, from Hanuman langurs to humans, males and females of most species experience different costs and benefits in reproducing, and these differences influence both...

  4. 4 Sex, Status, and Reproduction among the Apes
    (pp. 47-68)

    WE MUST REMEMBER that humans are primates, not deer or seals. Like other primates, we are complicated and diverse; ecological, social, and historical conditions can all contribute to the patterns we observe. Yet there are real regularities to how these forces interact, and sometimes we can make better sense of complex, apparently eclectic happenings by using the selection lens Consider witchcraft trials (more in chapter 10), during which Katherine Harrison was first immune from accusations, then targeted for death as a witch, then became safe once again through a powerful male accuser’s turnabout to protector. Self-interest and power differentials clearly...

  5. 5 Sex, Resources, Appearance, and Mate Choice
    (pp. 69-81)

    IN SHAKESPEARE’SRomeo and Juliet, Juliet’s father had promised her in marriage to a man his own age when she was twelve. Because she was in love with young and handsome Romeo, she complained. Her father’s answer was:

    An you will not wed, I’ll pardon you!

    Graze where you will, you shall not house with me;

    An you be mine, I’ll give you to my friend;

    An you be not, hang, beg, starve, die in the streets,

    For, by my soul, I’ll ne’er acknowledge thee,

    Nor what is mine shall never do thee good.

    (Romeo and Juliet, act 3, scene...

  6. 6 Sex, Resources, and Human Lifetimes
    (pp. 82-103)

    A GREAT PHILOSOPHER never married, and, in a possibly apocryphal story I read as a child, on his deathbed he called for all of his works to be set upon his lap. When the works had been brought, he sighed, “All of this is less than the weight of one grandchild.” (And, to complete the story tidily, he promptly died.) His insight is an important one: what are resources for, anyway, if not to build our families? As we move through the stages of our lives, our struggle for resources never ceases; in fact, our very lifetimes are shaped by...

  7. 7 Sex and Resource Ecology in Traditional Cultures
    (pp. 104-115)

    MEN AND WOMEN seek and use resources for reproductive success, but they can differ as much as peacocks and peahens in how they seek resources, what kinds of resources they seek, and how they use those resources. The reproductive ecology of the two sexes in humans, as in other mammals, creates opportunities for quite different uses of resources in reproductive competition by males and females and for different strategies (e.g., coalitions) to get them. In earlier chapters, I explored how our background of mammalian sex differences interacts with ecological conditions to yield different mating and resource systems. Here I want...

  8. 8 Sex, Resources, and Fertility In Transition
    (pp. 116-134)

    A CENTRAL QUESTION of this book is:exactly what, in any species or society, contributes to greater or lesser lifetime reproductive success? As we have seen, in most mammals and in the majority of traditional human societies for which data exist, status, power, or resource control enhance lifetime reproductive success, especially for men. Men’s reproductive variation in traditional societies arises mostly through differential polygyny—higher-status men can marry earlier and more often than other men, and often they can marry younger women, who are of higher reproductive value.

    Does this pattern have any relevance today? Two phenomena make it likely...

  9. 9 Nice Guys Can Win—In Social Species, Anyway
    (pp. 135-151)

    WE STARTED with very simple and general hypotheses about how resources affect reproductive success and why men and women typically have quite different resource strategies. But complexity has crept in. By the time we reached the demographic transition societies of the last chapter, forces such as markets, governmental rules, and societal mores clearly influenced men’s and women’s costs and benefits in resource, mating, and marriage decisions. Cultural transmission and evolution matter; simple hypotheses about selfish genes, favoring themselves and their copies in kin, or even simple reciprocation, can’t explain what we see. The world may be nasty, but it is...

  10. 10 Conflicts, Culture, and Natural Selection
    (pp. 152-169)

    KATHERINE HARRISON was a witch. After the death of her rich and powerful husband, she was accused of witchcraft based on events occurring years before. When accused, she was a rich widow who chose not to remarry, and she had no sons to protect her property. She continued to be accused for years and was even forced to leave her community, until, in 1670, her older daughter became engaged to a man from a powerful family. The future father-in-law, previously an attacker, became her protector, and the accusations ceased. Strong allies are important.

    The demographic and economic particulars of witchcraft...

  11. 11 Sex and Complex Coalitions
    (pp. 170-184)

    COALITIONS, like so many other phenomena, can be a reproductive strategy; and if this is true, male and female coalitions will tend to differ. Coalitions are not a widespread phenomenon; they occur in species that are long-lived, live in stable associations, have memory, and form friendships.

    Dolphin society is (like chimpanzee groups and many traditional societies) a “fission-fusion” society, in which individuals travel and feed together, splitting up and reforming. But the sexes differ. Among bottle-nosed dolphins, females often swim with each other. A female might swim with her mother today, her mother and sister tomorrow, and her friends next...

  12. 12 Politics and Reproductive Competition
    (pp. 185-197)

    HUMANS, like other primates, move almost imperceptibly from “coalitions” to “politics.” Arguably, coalitions represent part of the give-and-take of politics. We have come far from our starting consideration of the ecology of sex differences in reproduction. But a variety of current issues have precisely the characteristics that make this logical stretch worthwhile: intelligence and simple rules, interacting with environmental and historical particulars, create outcomes of increasing complexity and scale. If we can understand how men and women profited reproductively from differing resource strategies in the past, perhaps we can follow the emergence of complexity and begin to make sense of...

  13. 13 Sex, Resources, and Early Warfare
    (pp. 198-211)

    THE PRUSSIAN MILITARY strategist Carl von Clausewitz said war was simply “the continuation of state policy [politics] by other means.” Although warfare gives rise to some of the strongest, most tightly knit and potent international coalitions in modern times, that is surely not its evolutionary context, for states are a relatively modern phenomenon, whereas organized intergroup conflict among competing coalitions is older than humanity itself. Conflicts of interest, if not coalitions in open aggression, are universal among living things, and certainly lethal conflict exists in many species. Thus, it makes sense to begin our inquiry by focusing on simple conflict,...

  14. 14 Societal Complexity and the Ecology of War
    (pp. 212-224)

    IT IS NOT SURPRISING that the functional relationships of warfare are clearer in small, simple societies than in large politically complex ones. The transition from traditional-society warfare to the complex multinational warfare discussed in treatises on military history may seem almost unfathomable, but we must explore it if we are to understand whether modern warfare is functionally different from tribal warfare.

    The military historian John Keegan’s description of Alexander the Great suggests that even in large hierarchical armies, as during Philip’s and Alexander’s rule in Macedonia, personal characteristics, kin-group size, and the ability to inspire loyalty and reciprocity still were...

  15. 15 Wealth, Fertility, and the Environment in Future Tense
    (pp. 225-252)

    IT IS EASY TO IMAGINE that our evolutionary past is remote, unconnected to our lives today, and of interest only when we think of traditional societies or ancient history. Yet, as we saw in the last few chapters, our evolved tendencies interact with today’s novel environments. Cities, no less than rain forests and savannas,areour environments, and there is evidence that selection still acts on humans.¹ Just as soldiers in modern warfare display remnants of behaviors from past times, so do we all in our daily lives, as we live, work, and raise our families. Some physical and social...