Ethological bases of infanticide: a state-of-the-art approach to mammals

Abstract

Considering that infanticide can oppose the interests between offspring and parents, as well as between the two sexes, the aggressive behavior of adults against infants is considered a fundamental part of the organisms' strategy. Thus, this article aims to describe the types of infanticide, explaining the advantages of each biparental infanticidal behavior. The research was carried out using the Publish or Perish© software, with keywords such as “ethology”, “infanticide” and “mammals”, in English, Portuguese and Spanish. After selection and discarding, we selected 51 works, including scientific articles, theses and dissertations, covering a period of 40 years. We organized them systematically, separating the references into two approaches: (a) physiological and (b) sociobiological/ecological. The results indicate that infanticide behavior in mammals can be influenced by different factors, such as environmental stress, hormonal pathways, mainly oxytocin and vasopressin. Furthermore, studies have shown that there are individual differences in the behavioral response to parental care and infanticidal behavior, influenced by both the genotype and the environment in which individuals were raised. Infanticide behavior can also be seen as an adaptive parental strategy to increase the chances of survival and future reproduction. Ultimately, our results highlight the complexity of mammalian infanticide behavior, pointing to the importance of considering physiological, sociobiological and ecological factors in its analysis and interpretation.