1.0 Introduction
Science is all about knowledge and wonder
Science is all about the pursuit of what we find curious. As scientists, we ask questions, generate new knowledge, and refine our questions on the basis of that knowledge. We can study science through the lens of sex–sex appeal, sexual reproduction, sex and gender, and sexual orientation–as there are many questions regarding the topic that remain unanswered.
Consider the following questions
- Do animals besides humans have sex for fun? If so, which ones?
The authors of this text have often heard people claim that humans are exceptional in being the only, or one of the very few, animals that have sex for fun. But is this true? And how would anybody know whether other animals are having fun during sex? To look at the question from a different angle: why else would an animal have sex? Are they actually engaged in family planning?
- Why do animals, including humans, masturbate?
As humans, we are aware that humans masturbate, also known as sexual self-stimulation and autosexual behavior. However, we may be unaware that masturbation is prevalent across many species from cetaceans, to porcupines, to hummingbirds. Considering masturbation requires energy and in males wastes sperm and energy-rich ejaculate we may wonder when did masturbation evolve? What is the function or purpose of masturbation? Is that function the same in all species and sexes?
- Is homosexuality inherited?
The factors that influence sexual attraction are still far from clear. We will look at studies that argue for a genetic basis to at least some forms of same-sex sexual attraction and we’ll discuss studies that consider many non-genetic factors as well. In addition to addressing the question of homosexuality, we’ll encourage you to consider who is asking the questions. For example, why might some individuals feel compelled to seek a genetic basis for homosexuality? Why might others want to refute genetic arguments?
- What’s the function, if any, of the female orgasm?
Human female orgasm is a mystery in many respects. It can take many different forms, is not required for conception, and may occur outside of a “typical” sex act. Scientists have attempted to tackle the question of the function of the female orgasm, as well as the issue of whether female orgasm is evolutionarily adaptive (i.e., does it increase an individual’s reproductive success?).
Clarification of Terms
We will address sex and gender in detail in Chapter 8 and in class, but for now we want to clarify terms used in this textbook. “Male” and “female” are used to refer to biological sexes–in humans, the sex assigned at birth. In biology, females make the larger gamete (the egg) while males make the smaller gamete (the sperm). “Man” and “woman” are terms used to describe a person’s gender identity. Man and woman refer to a personal sense of one’s own gender and has nothing to do with the physical or behavioral characteristics that person has. People may also be non-binary, two-spirit, genderfluid, or have other gender identities. Many of our sources use the terms sex and gender interchangeably; however, we have modified those sources to use the terms that accurately reflect whether they are referring to biological sex or gender identity.
- Does the HPV vaccine lead to more teenage sex?
The human papillomavirus (HPV) is associated with several deadly cancers. Many health professionals advocate vaccinating adolescents against HPV prior to the onset of sexual activity. However, this recommendation involves parents making a decision that, for some, seems like giving their children “permission” to be sexually active. Thus, there has been some question about whether receiving the vaccine will make an individual more likely to engage in sexual activity, especially at an early age. We’ll discuss this question in the following pages. But first, what do you think?
Points to Ponder
- Does the HPV vaccine lead to more teenage sex? What do you think?
- How would you go about gathering evidence to answer this question?
- How would you address any of the above questions?
These questions, and limitless others, all lead to a central tenet of this text: SEX, AND SCIENCE, ARE EVERYWHERE. Sex affects human lives along many dimensions from how we interact as societies, to individual health, to evolutionary success. We’ll use the evolution and biology of sex to explore science as a discipline, both a body of knowledge and a way of creating knowledge. By the end of our discussion, you’ll be able to address (if not actually answer) all of the above questions, as well as many others.
Important Note: Sex-positive versus pro-sex
The authors of this text are working from a “sex-positive” viewpoint. By “sex-positive,” we mean that we will not be vilifying consensual sex in any form. We view sex as a natural product of biological forces, expressed in a diversity of presentations, and ideally associated with healthy individuals and societies. This is different from being “pro-sex.” We hope to never make recommendations or express opinions about individual choices related to sexual activity, including your ability to choose abstinence or express asexuality.
Please keep this “sex-positive” viewpoint in mind during your reading, our in-class discussions, and your interactions with peers. You should be able to express your own opinions and be heard, while respecting the opinions of others, but in the end, our class is a “sex-positive” space.
Content on this page was originally published in The Evolution and Biology of Sex by Sehoya Cotner & Deena Wassenberg and has been expanded and updated by Katherine Furniss & Sarah Hammarlund in compliance with the original CC-BY-NC 4.0 license.
