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Author: Todd K. Shackelford
Publisher: Springer Science & Business Media
ISBN: 0387280391
Category : Science
Languages : en
Pages : 286
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Book Description
In species with internal fertilization, sperm competition occurs when the sperm of two or more males simultaneously occupy the reproductive tract of a female and compete to fertilize an egg (Parker, 1970). A large body of empirical research has demonstrated that, as predicted by sperm competition theory, males and females in many species possess anatomical, behavioral, and physiological adaptations that have evolved to deal with the adaptive challenges associated with sperm competition. Moreover, in recent years, evolutionary biologists and psychologists have begun to examine the extent to which sperm competition may have been an important selective pressure during human evolution. Some research has suggested that male humans, like males of many bird, insect, and rodent species, might be able to adjust the number of sperm they inseminate according to the risk of sperm competition. Other research has examined whether such responses might be accompanied by psychological changes that motivate human males to pursue copulations when the risk of sperm competition is high. Furthermore, there is research suggesting that aspects of human penile anatomy might function to enhance success in sperm competition. Much of this work has been controversial; some of the findings have been disputed and others have been greeted with skepticism. However, the idea that some aspects of human psychology and behavior might best be understood as adaptations to sperm competition remains intriguing and, in certain cases, very persuasive.
Author: Todd K. Shackelford
Publisher: Springer Science & Business Media
ISBN: 0387280391
Category : Science
Languages : en
Pages : 286
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Book Description
In species with internal fertilization, sperm competition occurs when the sperm of two or more males simultaneously occupy the reproductive tract of a female and compete to fertilize an egg (Parker, 1970). A large body of empirical research has demonstrated that, as predicted by sperm competition theory, males and females in many species possess anatomical, behavioral, and physiological adaptations that have evolved to deal with the adaptive challenges associated with sperm competition. Moreover, in recent years, evolutionary biologists and psychologists have begun to examine the extent to which sperm competition may have been an important selective pressure during human evolution. Some research has suggested that male humans, like males of many bird, insect, and rodent species, might be able to adjust the number of sperm they inseminate according to the risk of sperm competition. Other research has examined whether such responses might be accompanied by psychological changes that motivate human males to pursue copulations when the risk of sperm competition is high. Furthermore, there is research suggesting that aspects of human penile anatomy might function to enhance success in sperm competition. Much of this work has been controversial; some of the findings have been disputed and others have been greeted with skepticism. However, the idea that some aspects of human psychology and behavior might best be understood as adaptations to sperm competition remains intriguing and, in certain cases, very persuasive.
Author: Robert L. Smith
Publisher: Elsevier
ISBN: 032314313X
Category : Science
Languages : en
Pages : 710
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Book Description
Sperm Competition and the Evolution of Animal Mating Systems describes the role of sperm competition in selection on a range of attributes from gamete morphology to species mating systems. This book is organized into 19 chapters and begins with the conceptualization of sperm competition as a subset of sexual selection and its implications for the insects. The following chapter describes the relationship between multiple mating and female fitness, with an emphasis on determining the conditions under which selection on females is likely to counteract selection on males for avoiding sperm competition. Other chapters consider the female perspective on sperm competition; the evolutionary causation at the level of the individual male gamete; and the correlation of high paternal investment and sperm precedence in the insects. The remaining chapters are arranged phylogenetically and explore the sperm competition in diverse animal taxa, such as the Drosophila, Lepidoptera, spiders, amphibians, and reptiles. These chapters also cover the evolution of direct versus indirect sperm transfer among the arachnids or the problem for kinship theory presented by multiple mating and sperm competition in the Hymenoptera. This book further discusses the remarkable potential for sperm competition among certain temperate bat species whose females store sperm through winter hibernation and the mixed strategies and male-caused female genital trauma as possible sperm competition adaptations in poeciliid fishes. The concluding chapter examines the predictions concerning testes size and mating systems in the primates and the possible role of sperm competition in human selection. This book is of great value to reproductive biologists and researchers.
Author: Robin Baker
Publisher: eBook Partnership
ISBN: 8461686500
Category : Science
Languages : en
Pages : 853
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Book Description
Since the 1970s, behavioural ecologists and evolutionary biologists have been fascinated by the biological implications of sperm from different males competing for fertilization of the egg in the female reproductive tract. But until Human Sperm Competition there had never been a discussion of the phenomenon for the human species in book form, despite its relevance for a full understanding of human reproduction.The book is a pioneering analysis of the evolutionary biology of human sexuality, proposing that all aspects have been shaped by the phenomenon of sperm competition. Written 20 years ago in 1993-94, the print edition was published in 1995. Despite its age that book's contents are as relevant now as they were two decades ago. Perhaps even more so, because since Baker and Bellis' demonstration that human sperm competition could actually be studied in a variety of ways a number of research groups have taken up the challenge where they left off. Most of these groups have obtained results that build firmly upon Baker and Bellis' original work. A few others created important dialogues. None though have destroyed any crucial part of the foundation first laid down in that 1995 book. But the main way in which Human Sperm Competition remains relevant to this day is that for various reasons - some cultural, some procedural, and yet others due to sheer opportunity - Baker and Bellis were able to do a number of experiments that others since have not had the opportunity to repeat. And the results of those unique experiments were presented in Human Sperm Competition and nowhere else.In the first half of the book the authors explore the role of sperm competition in the evolution of human sexual characteristics, considering for example the architecture of the female reproductive tract, the reasons for male and female infidelity and the possible biological reasons for homosexuality, masturbation and orgasm.In the second half, the mechanism of sperm competition is evaluated in detail, together with the evidence for and the implications of the authors' own Kamikaze Sperm Hypothesis. Human Sperm Competition sets out the thesis that adopting an evolutionary approach to human reproduction exposes the subtle and sophisticated ways in which human sexual anatomy, physiology and behaviour are designed to interact. As a species, understanding this sexual legacy helps explain how we reproduce today and why problems with fertility arise.Over the years, Human Sperm Competition has become a classic in the study of human sexual biology - but although the original hardback is still in print rising costs plus perhaps its classic status have priced it beyond those students who might most wish to read its contents. This digital edition of the original 1995 publication, but at a student-friendly price, now solves this problem.
Author: Todd K. Shackelford
Publisher:
ISBN:
Category :
Languages : en
Pages : 116
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Book Description
Author: Nicholas Pound
Publisher: Taylor & Francis
ISBN: 9780387280363
Category : Health & Fitness
Languages : en
Pages : 322
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Book Description
This volume presents the intricate ways in which sperm compete to fertilize eggs and how this has prompted reinterpretations of breeding behavior from a biological perspective. Sperm Competition in Humans: Classic and Contemporary Readings provides a theoretical framework for the study of sperm competition and also discusses the roles of females and the relationships between paternal care in sperm competition. The chapters focus on everything from evolutionary biology to taxonomic development.
Author: Todd K. Shackelford
Publisher: Oxford University Press
ISBN: 0199908303
Category : Psychology
Languages : en
Pages : 384
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Book Description
Sexual conflict -- what happens when the reproductive interests of males and females diverge -- occurs in all sexually reproducing species, including humans. The Oxford Handbook of Sexual Conflict in Humans is the first volume to assemble the latest theoretical and empirical work on sexual conflict in humans from the leading scholars in the fields of evolutionary psychology and anthropology. Following an introductory section that outlines theory and research on sexual conflict in humans and non-humans, ensuing sections discuss human sexual conflict and its manifestations before and during mating. Chapters in these sections address a range of factors topics and factors, including: - Sexual coercion, jealousy, and partner violence and killing - The ovulatory cycle, female orgasm, and sperm competition - Chemical warfare between ejaculates and female reproductive tracts Chapters in the next section address issues of sexual conflict after the birth of a child. These chapters address sexual conflict as a function of the local sex ratio, men's functional (if unconscious) concern with paternal resemblance to a child, men's reluctance to pay child support, and mate expulsion as a tactic to end a relationship. The handbook's concluding section includes a chapter that considers the impact of sexual conflict on a grander scale, notably on cultural, political, and religious systems. Addressing sexual conflict at its molecular and macroscopic levels, The Oxford Handbook of Sexual Conflict in Humans is a fascinating resource for the study of intersexual behavior.
Author: David M. Buss
Publisher: Oxford University Press
ISBN: 0197536433
Category : Psychology
Languages : en
Pages : 865
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Book Description
The scientific study of human mating has mushroomed over the past three decades, and this growth in turn has generated a proliferation of evolving literature revealing fresh discoveries about mate attraction, mate choice, mate retention, marital satisfaction, jealousy, infidelity, intimate partner violence, breakups, internet dating, cyberstalking, and sexual coercion. In The Oxford Handbook of Human Mating, editor David M. Buss showcases contributions from the best and the brightest scientists in the field, providing up-to-date summaries of theories and empirical evidence of the science of human mating strategies. Much of the research in the field is guided by sexual selection theory. Over 150 years after Darwin's proposal of sexual selection theory, it has become the most important overarching theoretical framework for the scientific study of the mating strategies of all sexually reproducing species, including humans. A mountain of research centered around Darwin's classic book has documented the many complexities of human mate competition and mate choice; how these processes differ between the sexes; and how they differ as a function of sex ratio, mate value, social contexts, ovulation cycles, personality characteristics, and cultural norms and mating rituals. Thus, the science is now ripe for a collection of work by eminent scholars in the field. David M. Buss is a leading researcher and pioneer in the study of human mating strategies, and he applies his expertise to the curation of this volume, which includes major sections covering theories of human mating; mate selection and mate attraction; mate competition; sexual conflict in mating; human pair bonding; the endocrinology of mating; and mating in the modern world.
Author: Scott Solomon
Publisher: Yale University Press
ISBN: 0300224508
Category : Social Science
Languages : en
Pages : 225
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Book Description
An evolutionary biologist provides surprising insights into the changing nature of Homo sapiens in this “important and an entertaining read" (Choice). In Future Humans, evolutionary biologist Scott Solomon draws on recent discoveries to examine the future evolution of our species. Combining knowledge of our past with current trends, Solomon offers convincing evidence that evolutionary forces are still affecting us today. But how will modernization—including longer lifespans, changing diets, global travel, and widespread use of medicine and contraceptives—affect our evolutionary future? Solomon presents an entertaining and accessible review of the latest research on human evolution in modern times, drawing on fields from genomics to medicine and the study of our microbiome. Drawing together topics ranging from the rise of online dating and Cesarean sections to the spread of diseases such as HIV and Ebola, Solomon suggests that we are entering a new phase in human evolutionary history—one that makes the future less predictable and more interesting than ever before.
Author: Steven M. Platek
Publisher: Cambridge University Press
ISBN: 1139458043
Category : Science
Languages : en
Pages : 234
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Book Description
Although commonly believed that males are more promiscuous than females, new research has revealed that female infidelity is a common occurrence throughout the animal kingdom. Female Infidelity and Paternal Uncertainty is the first book to address how males deal with the consequences of female infidelity and the strategies they have evolved to try to avoid the possibility of raising an offspring they unknowingly did not sire. Each chapter deals with a specific evolved strategy developed to aid males in either limiting opportunities for their mate to be unfaithful or to 'correct' the by-products of infidelity should it occur. With sections including mate guarding, intra-vaginal tactics and paternity assessment, this book will appeal to researchers and graduate students in behavioral biology, evolutionary psychology, human sexuality, anthropology, sociology, reproductive health and medicine.
Author: Catherine A. Salmon
Publisher: Oxford University Press
ISBN: 0195320514
Category : Family & Relationships
Languages : en
Pages : 377
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Book Description
'Family Relationships' brings together leading theorists and researchers from evolutionary psychology and related disciplines to illustrate the ways in which an evolutionary perspective can inform our study and understanding of family relationships.
