My co-authors and I are pleased to share our recently published article: Towers JR, Hallé MJ, Symonds HK, Sutton GJ, Morton AB, Spong P, Borrowman JP & Ford JKB (2018) Infanticide in a mammal-eating killer whale population. Scientific Reports 8:4366 This article is open access at: https://www.nature.com/ articles/s41598-018-22714-x and can also be found at: https://www.researchgate.net/publication/323880722_Infanticide_in_a_mammal- eating_killer_whale_population Abstract: Infanticide can be an extreme result of sexual conflict that drives selection in species in which it occurs. It is a rarely observed behaviour but some evidence for its occurrence in cetaceans exists in three species of dolphin. Here we describe observations of an adult male killer whale (Orcinus orca) and his post-reproductive mother killing a neonate belonging to an unrelated female from the same population in the North Pacific. This is the first account of infanticide reported in killer whales and the only case committed jointly by an adult male and his mother outside of humans. Consistent with findings in other social mammals, we suggest that infanticide is a sexually selected behaviour in killer whales that could provide subsequent mating opportunities for the infanticidal male and thereby provide inclusive fitness benefits for his mother. regards, Jared Towers Alert Bay BC jrtowers@gmail.com