Students' conceptions on the origins of human social behavior are poorly understood. The aim of this research was to quantitatively evaluate the conceptions on the origins of certain types of human behavior expressed by a group of 1,212 Brazilian university students. Results suggest that regardless of either religiosity or evolutionary commitments, the majority of the students advocate nurture-based arguments to explain human social behavior. Data also suggest that behaviors considered to be typically human are better explained by nurture-based arguments. The preference for nurture-based explanations may be due to the absence of the theme "behavior" in biology curriculum in secondary schools. The possibility of teaching aspects of human biology that are known to be influenced both by nature and nurture-based explanations is discussed. We conclude that, despite the enormous influence of evolutionary theory on recent western thought, Brazilian students do not seem to perceive its legacy concerning the origins of human social behavior.

The role of epidemics in the demographic collapse of the Amerindians in Mexico and Andean America after the arrival of the Spanish is discussed. Ernst Mayr's categories of ultimate (or evolutionary) and proximal (or functional) causes are used to argue that ultimate causes, such as genetics, which gave the Spanish immunological resistance, were manifested in a very stratified setting, triggering the destruction of the Incas and Aztecs. Recent interpretations of colonization have played down the importance of epidemics or combined them with social, economic, and political factors, interpreted here as proximate causes. We understand that only by articulating these two categories can the importance of epidemics in the Spanish conquest of Latin America be understood.

A reprodução sexuada já foi considerada universal, e posteriormente, a forma mais perfeita de reprodução. Todavia, a partir de meados do século XIX, pesquisas no nível celular colocaram em xeque a ideia de que tipos de reprodução assexuadas fossem primitivos ou inferiores. Ao longo do século XX, e adentrando no XXI, hipóteses foram levantadas para explicar as vantagens da reprodução sexuada sobre a assexuada assim como o que permitiria a reprodução sexuada se manter quando seria mais vantajoso se reproduzir de forma assexuada. A mais importante e conhecida é a hipótese da Rainha Vermelha. Paralelamente, vários trabalhos procuraram entrever as pressões ecológicas que permitiram e favoreceram o aparecimento da reprodução sexuada em um cenário situado há cerca de dois bilhões de anos. O objetivo desse trabalho é revisar respostas históricas que marcaram o estudo da origem, da evolução e da manutenção da reprodução sexuada, identificando algumas das principais questões que a comunidade científica elaborou nos últimos duzentos anos.