During the last decade, the study of behavioural endocrinology has gone through a very exciting phase. New technologies have appeared which have allowed us to answer new questions; the present book is a reflection of this progress. In the eariy1970's, the advent of steroid radioimmunoassays (RIA) for the first time permitted measurement of gonadal and adrenal steroids in small aliquots of plasma. It thus became possible to measure these hormones repeatedly in the same animals (Le., to undertake longitudinal studies) and also to assay them in small-sized animals such as the rat or the ring dove which had traditionally been favourite subjects for behavioural endocrinologists. With the RIA's, two major goals have been achieved. On one hand, it has been possible to ascertain that those hormones, whose action on behaviour had been postulated on the basis of gonadectomy and hor mone therapy experiments, were actually present in adequate amounts in the intact animals at the time they were supposed to exert their ac tion. On another hand, it has become feasible to measure the circulat ing levels of steroids induced by treatments with exogenous hormones. This revealed that in a number of the early experiments the hormonal conditions which had been tested were completely outside the physi ological range (plasma levels of steroids being several order of magni tude above physiological levels after the injections) and a reinterpre tation of the results was thus needed.

Inhalt
1 Brain Mechanisms.- Sites of Action of Ovarian Hormones in the Regulation of Oestrous Responsiveness in Rats.- Mechanisms of Oestrogen-Progestin Interactions in the Regulation of Lordosis in Female Guinea Pigs.- Diurnal Variations in the Sensitivity of the Brain to Oestrogens: Behavioural and Biochemical Studies.- Catechol Oestrogens: Their Contraceptive Effects and Possible Involvement in Some Reproductive Processes of the Rat.- Cholinergic Regulation of Feminine Sexual Behaviour in Laboratory Rats.- Brain Mechanisms of Maternal Behaviour in the Rat.- Potency and Fertility: Hormonal and Mechanical Causes and Effects of Penile Actions in Rats.- Endorphin-Monoamine Interaction and Steroid-Dependent Behaviour.- ACTH and Grooming Behaviour in the Rat.- 2 Sexual Differentiation.- Genetic Determinants of Sexual Differentiation.- The Interaction of Circulating Oestrogens and Androgens in Regulating Mammalian Sexual Differentiation.- Reproductive Neuroendocrine Rhythms.- Hormonal Influence on Sexual Differentiation of Rat Brain Anatomy.- Hormone-Dependent Brain Development and Behaviour.- Sex Steroids and the Differentiation and Activation of Avian Reproductive Behaviour.- 3 Testosterone Metabolism.- Brain Testosterone Metabolism and Sexual Behaviour in Birds.- Testosterone Metabolism and Sexual Differentiation in Quail.- Hormone-Mediated Behavioural Transitions: A Role for Brain Aromatase.- Hormonal Specificity and Activation of Social Behaviour in the Male Zebra Finch.- Hormones and Different Tests for Aggression with Particular Reference to the Effects of Testosterone Metabolites.- Exposure to Odour During Development and Hypothalamic Metabolism of Testosterone.- 4 Endocrine Cycles.- Male-Female Interaction in the Hamster: Seasonal and Hormonal Effects.- The Control of Sexual Behaviour in the Female Hamster.- Social Factors Controlling Puberty in the Female Mouse.- Sexual Behaviour and Endocrine Changes During Reproductive Maturation and Aging in the Avian Male.- Hormonal Correlates of Behavioural Development in Male Zebra Finches.- Prolactin in Avian Reproductive Cycles.- Population Endocrinology of the Female Pied Flycatcher, Ficedula Hypoleuca.- Control of Male Sexual Behaviour in the Canadian Red-Sided Garter Snake.- 5 Bird Behaviour.- Behavioural Self-Feedback Control of Endocrine States.- Hormones and Brain Mechanisms of Vocal Behaviour in Non-Vocal Learning Birds.- Reproductive Physiology and the Defence of Genetic Paternity in the Ring Dove, Streptopelia risoria.- Biparental Care in Birds: Mechanisms Controlling Incubation Bout Duration.- Specific Short-Latency Effects of Oestradiol and Testosterone on Distractibility and Memory Formation in the Young Domestic Chick.- Reproductive Behaviour in Hens.- Abbreviations.