There is extensive evidence that vertebrates of all classes have the ability to control the sexes of the offspring they produce. Despite dramatic differences in the mechanisms by which different taxa determine the initial sex of offspring, each group has found its own way of adjusting offspring sex ratios in response to social and environmental cues. For example, stress is a well-known modulator of offspring sex in members of all groups studied to date. Food availability, and limitation in particular, is another common cue that stimulates biases in offspring sex ratios in a wide variety of species. Offspring sex can be adjusted at the primary level, which occurs prior to conception, or at the secondary level, during embryonic development. While the mechanistic pathways that ultimately result in sex ratio biases and the developmental time-points sensitive to those mechanisms likely differ among taxa, the key involvement of steroid hormones in the process of sex ratio adjustment appears to be pervasive throughout. This book reviews the systems of sex determination at play in different vertebrate groups, summarizes the evidence that members of all vertebrate taxa can facultatively adjust offspring sex, and discusses when and how these adjustments can take place.

Choosing Unsafe Sex focuses on the ways in which condom refusal and beliefs regarding HIV testing reflect women's hopes for their relationships and their desires to preserve status and self-esteem. It also discusses the related issue of seropositivity concealment or non-disclosure. Many of the inner-city women who participated in Dr. Sobo's research were seriously involved with one man, and they had heavy emotional and social investments in believing or maintaining that their partners were faithful to them. Uninvolved women had similarly heavy investments in their abilities to identify or choose potential partners who were HIV-negative. In either case, women sought to present and to view themselves as wise and their men as monogamous. Women did not see themselves as being at risk for HIV infection, and so they saw no need for condoms. But they did recommend that other women use them; they saw other women as quite likely to be involved with sexually unfaithful men. Choosing Unsafe Sex includes recommendations for educational strategies that are sensitive to cultural expectations for relationships. Dr. Sobo's findings have significance not only for inner-city HIV/AIDS educators but for all who seek a deeper understanding of mainstream assumptions about heterosexual relationships.

The Arthur M. Sackler Colloquia of the National Academy of Sciences address scientific topics of broad and current interest, cutting across the boundaries of traditional disciplines. Each year, four or five such colloquia are scheduled, typically two days in length and international in scope. Colloquia are organized by a member of the Academy, often with the assistance of an organizing committee, and feature presentations by leading scientists in the field and discussions with a hundred or more researchers with an interest in the topic. Colloquia presentations are recorded and posted on the National Academy of Sciences Sackler colloquia website and published on CD-ROM. These Colloquia are made possible by a generous gift from Mrs. Jill Sackler, in memory of her husband, Arthur M. Sackler.

Gender can be difficult to define, but it's something that's a part of all of us and who we are. This book isn't meant to answer all the questions or tell you how you identify. It's meant to help kids and grownups understand gender and create an open and safe environment for kids to question, experiment, and discover their authentic selves. Meet A Kids Co., a new kind of media company with a collection of beautifully designed books that kickstart challenging, empowering, and important conversations for kids and their grownups. Learn more about us at akidsco.com.

Sex Differences in Physiology is an all-encompassing reference that details basic science research into sex differences in all physiological fields. It includes scientific discoveries concerning sex differences in cardiovascular, respiratory, renal, gastrointestinal, and musculoskeletal physiology. In addition, coverage of the development, endocrinology, neurophysiology, immunity, and metabolism is included, making this important reference a resource that will meet the needs of investigators interested in incorporating sex differences into their research programs, while also providing clinicians with the basis for providing the best sex-based medical treatment options available. Provides a sweeping, organ-by-organ review of currently observed sex differences in animal models and human disease Explains how sex differences influence physiology and disease Provides the critical knowledge on sex differences for better understanding of prevention and treatment of diseases

When Charles Darwin first proposed Sexual Selection Theory, he suggested two mechanisms: competition among males and choice by females. Although their importance is long established and extremely well understood, their mirror images have remained largely underappreciated; males also choose, and females also compete. The combination of male mate choice (MMC) and female competition (FC) may be one of the most overlooked yet important and intriguing phenomena in modern sexual selection theory. This novel text reviews our current understanding of MMC and FC, highlighting the important connections between them. It places both concepts in the context of related fields such as female choice, mating systems, and sexual selection theory more broadly. A truly holistic approach is provided which takes all the relevant elements into consideration, especially the relative roles of MMC and FC, female ornamentation, their evolutionary consequences, and their genetic basis. Considering male mate choice and female competition in this way as effectively two sides of the same coin creates a powerful paradigm for a more complete understanding of sexual selection. Male Choice, Female Competition, and Female Ornaments in Sexual Selection will be suitable for both graduate students and researchers interested in sexual selection from an evolutionary, psychological, and anthropological perspective. It will also appeal to a broader audience of behavioural ecologists and evolutionary psychologists.

This practical guide shows readers a natural method of choosing the sex of a baby. It gives advice on health, diet, sperm count and ovulation in an easy-to-follow manner. The testimonies of numerous parents throughout the world reflects the success of the author's method.

When Charles Darwin first proposed Sexual Selection Theory, he suggested two mechanisms: competition among males and choice by females. Although their importance is long established and extremely well understood, their mirror images have remained largely underappreciated; males also choose, and females also compete. The combination of male mate choice (MMC) and female competition (FC) may be one of the most overlooked yet important and intriguing phenomena in modern sexual selection theory. This novel text reviews our current understanding of MMC and FC, highlighting the important connections between them. It places both concepts in the context of related fields such as female choice, mating systems, and sexual selection theory more broadly. A truly holistic approach is provided which takes all the relevant elements into consideration, especially the relative roles of MMC and FC, female ornamentation, their evolutionary consequences, and their genetic basis. Considering male mate choice and female competition in this way as effectively two sides of the same coin creates a powerful paradigm for a more complete understanding of sexual selection. Male Choice, Female Competition, and Female Ornaments in Sexual Selection will be suitable for both graduate students and researchers interested in sexual selection from an evolutionary, psychological, and anthropological perspective. It will also appeal to a broader audience of behavioural ecologists and evolutionary psychologists.

Autonomy is fundamental to liberalism. But autonomous individuals often choose to do things that harm themselves or undermine their equality. In particular, women often choose to participate in practices of sexual inequality&—cosmetic surgery, gendered patterns of work and childcare, makeup, restrictive clothing, or the sexual subordination required by membership in certain religious groups. In this book, Clare Chambers argues that this predicament poses a fundamental challenge to many existing liberal and multicultural theories that dominate contemporary political philosophy. Chambers argues that a theory of justice cannot ignore the influence of culture and the role it plays in shaping choices. If cultures shape choices, it is problematic to use those choices as the measure of the justice of the culture. Drawing upon feminist critiques of gender inequality and poststructuralist theories of social construction, she argues that we should accept some of the multicultural claims about the importance of culture in shaping our actions and identities, but that we should reach the opposite normative conclusion to that of multiculturalists and many liberals. Rather than using the idea of social construction to justify cultural respect or protection, we should use it to ground a critical stance toward cultural norms. The book presents radical proposals for state action to promote sexual and cultural justice.