The Bonnet Macacque, one of the 89 species in which females have been shown to commit infanticide (Image Credit: Vino Rex, CC BY 2.0, Image Cropped)
The evolution of infanticide by females in mammals (2019) Lukas & Huchard, Philsophical Transactions of the Royal Society – Biological Sciences, https://doi.org/10.1098/rstb.2018.0075
The practice of male mammals killing their rival’s cubs has been well-documented by wildlife biologists. The image of a male lion striding away from a pride with a dead cub in his mouth is quite haunting (spare a though for Scar’s kids when Simba takes over again). But infanticide by female mammals has received less attention.
Whilst males generally only kill young to ensure they have more access to mates, the motivations behind infanticide in females are more complex. It ultimately comes down to resource competition, but the resources themselves are myriad – milk, availability of space, care from more than one ‘parental’ figure (allocare), and social status. These four resources make up the competing hypotheses as to why females commit infanticide. This week’s researchers wanted to know what factors of a species biology increased the likelihood of a mother to kill an infant of the same species.