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Cetaceans are known to frequently engage in sexual behavior; however, the lack of male parental investment in offspring makes assessment of male reproductive success difficult. We assessed paternity in a small population (mean individuals sighted per year = 93) of Atlantic spotted dolphins (Stenella frontalis (G. Cuvier, 1829)) utilizing noninvasively collected fecal material. Samples (n = 88) were collected from dolphins from four social clusters. Of the 29 offspring tested, 34.5% were assigned paternity, resulting in 10 paternities assigned to seven males. Our study indicates that achieving a certain age is a potential precursor for males to mate successfully, as 18 years was the youngest estimated age of a male at the time of calf conception. In all pairings but one, the males were older than the female (mean age difference = 7.7+ years). Successful males were from two of the four social clusters and males most often mated within their social group or with females from the next geographically closest group. The study combines genetic data with known maternal pedigree information and reveals patterns in the overall mating system in a cetacean species where reproductive success of males was previously unknown. Les cetaces participent frequemment a des comportements sexuels, cependant l'absence d'investissement paternel envers les jeunes rend difficile l'evaluation du succes reproductif des males. Nous avons determine les paternites dans une petite population (nombre moyen d'individus apencus par annee = 93) de dauphins tachetes de l'Atlantique (Stenella frontalis (G. Cuvier, 1829)) par des recoltes de materiel fecal, une technique non invasive. Les echantillons (n = 88) proviennent de quatre regroupements sociaux. Nous avons determine; la paternite de 34,5 % des 29 jeunes testes, obtenant ainsi dix paternites attribuees a sept males. Notre etude revele que l'atteinte d'un certain age est une condition potentielle pour l'accouplement reussi chez les males, puisque l'age estime le plus jeune d'un male a la conception d'un petit est de 18 ans. Dans tous les accouplements sauf un, le male est plus age que la femelle (difference d'age moyenne = 7,7+ ans). Les males qui ont reussi appartiennent a deux des quatre regroupements sociaux et les males s'accouplement le plus souvent au sein de leur groupe social ou avec des femelles du groupe le plus rapproche geographiquement. Notre etude combine des donnees genetiques et des donnees d'ascendance maternelle et met en lumiere des patrons dans le systeme global d'accouplement chez une espece de cetace dont le succes reproductif des males etait encore inconnu. [Traduit par la Redaction], Introduction Knowledge of genetic relatedness is key to addressing questions about behavior and conservation in natural populations. Pedigrees provide the most complete picture of relatedness in a population and assessing [...]

Many scholars regard the psychology of learning as not interesting partly because the field's teaching techniques are not relevant to ordinary life. Using examples from common experience could demonstrate the value of learning theory.

Tamotsu Shibutani is a contemporary proponent of the Chicago School of pragmatic sociology who has devoted his academic efforts to using the Chicago School of pragmatism to analyze problems of contemporary social life and to refine the theoretical tools available to the discipline of sociology. He has evaluated such topics as the Japanese relocation centers, the social construction of rumor, demoralization in Army life, the dynamics of ethnic stratification, and the resolution of ethnic tensions. Shibutani's books on social psychology and general sociology synthesize micro and macro variables, with careful attention to both agency and social control. His work is free of metaphysical puzzles and is true to the scientific method, clearly reflecting the essence of the Chicago School of pragmatic sociology.

If biologists are going to incorporate learning into theories of animal behavior, will not go all the way and incorporate the enormous literatures on Pavlovian conditioning, plus those on operant and observational learning?

Mealey's data do not support her dichotomous model of primary and secondary sociopathy; this data supports the view that there is a continuum of degrees of sociopathy, from zero to the maximal manifestation. There are multitudes of factors that can contribute to sociopathy - from both genetic and environmental sources - and the countless different mixes of them can produce multiple degrees and variations of sociopathic behavior.