
More specifically, we argue that the well-known female-male difference in the concordance of genital and subjective arousal may contribute to well-known differences in sexual specificity and plasticity/fluidity. With respect to sex/gender differences, we describe how these positive feedback processes might be amplified in men compared with women, potentially substantially driven by differences in the constraints and affordances of female and male anatomy. We describe how these phenomena might be accounted for by processes in which mind body feedback loops amplify some sexual responses over others on multiple levels, which we refer to as the Reward Competition Feedback (RCF) model. Is sexual orientation an evolutionary adaptation or social construct? With respect to sexual preferences, to what extent are we "born that way" and to what extent does learning matter? This chapter discusses how nature and nurture may interact to shape sexual motivation by reviewing existing literature on sexual preferences and orientations, as well as by considering sex/gender differences in erotic plasticity, sexual fluidity, and the specificity of sexual arousal. Finally, we consider some of the ethical implications of models in which sexual orientation might be shaped by experiences over the course of development.KeywordsSexual preferenceSexual orientationSexGenderDevelopmentLearning We further provide convergent support for RCFīy reviewing preexisting theories of sexual learning. We describe how these phenomena might be accounted for by processes in which mind-body feedback loops amplify some sexual responses over others on multiple levels, which we refer to as the Reward Competition Feedback (RCF) model. Is sexual orientation an evolutionary adaptation or social construct? With respect to sexual preferences, to what extent are we “born that way” and to what extent does learning matter? This chapter discusses how nature and nurture may interact to shape sexual motivation by reviewing existing literature on sexual preferences and orientations, as well as by considering sex/gender differences in erotic plasticity, sexual fluidity, and the specificity of sexual arousal. Across subjects, much of his research revolved around bird migration, a topic that fascinated him throughout his lifetime and that he studied in daring and persistent experiments across continents.KeywordsCircannualCircadianMulti-pacemakerInternal resonanceMelatoninMigrationBehaviorBird Gwinner pioneered many fields that unfolded beyond his lifetime, for example, research on light pollution and urbanization in wild organisms. Gwinner also elaborated contributions of reproductive and adrenocortical hormones to avian annual cycle behavior, and his studies of multiple pacemaker interactions and the role of melatonin contributed majorly to understanding circadian systems. He is most recognized for his seminal work and persistently authoritative monography on circannual rhythms. Gwinner combined these backgrounds to coin his trademark, integrative research on biological timekeeping under both natural and experimental conditions. Following his doctorate in classical ethology, further formative experiences included postdoctoral training in biological rhythms and behavioral endocrinology. Female spotted hyenas thus present a mosaic in which some neuroanatomical traits are also remarkably masculinized, whereas others are not.Įberhard (Ebo) Gwinner was a German ornithologist and chronobiologist. De Vries (then at the University of Massachusetts, Amherst) characterized traditional sex differences in perineal muscles and motoneurons (Forger et al., 1996), a diminished sex difference in the hypothalamus (Fenstermaker et al., 1999), and absent or possibly reversed sex differences in arginine vasopressin innervation of the forebrain (Rosen et al., 2006) collaboration with Dennis McFadden (University of Texas, Austin) confirmed female masculinization of otoacoustic emissions.

Additional anatomical studies were facilitated by (1) access to brain and other central nervous system (CNS) tissues obtained primarily from hyenas culled in Northern Kenya (requiring an expedition on which Glickman had to be accompanied by armed guards during a politically unstable period) and (2) auditory studies of control, antiandrogen-treated, and gonadectomized animals living at the FSBR.
