mating with multiple males to confuse paternity, Hrdy, Sarah Blaffer thereby reducing the risk of infanticide. LYNNE A. ISBELL In her two later books, Hrdy focused on University of California, Davis, United States mothers and infants. Hrdy (1999) explored why humans can reproduce again before the previous ofspring is nutritionally independent, a feat not accomplished by other hominoids. Sarah Blafer Hrdy (b. 1946) is a highly recog- She concluded that such rapid reproduction nized pioneer in modernizing our understanding could have only evolved in species that are of the evolutionary basis of female behavior in cooperative breeders, who, by defnition, obtain both nonhuman and human primates. Hrdy help from others to care for and feed their young. earned her B.A. (1969) from Radclife College Tis book won the W. W. Howells Book Award and her Ph.D. (1975) in anthropology from from the Biological Anthropology Section of Harvard University. Her early work (Hrdy 1977), the American Anthropological Association in anchored by a feld study of Hanuman langurs 2001. In her next book, Hrdy (2009) pursued the (Semnopithecus entellus)inIndia,arguedthat implications of helpers for child development. infanticide in primates (including humans) is She argued that natural selection would have an adaptive behavioral expression of sexual favored children who could more easily monitor, selection acting upon individuals, rather than assess, and engage with helpers, and that this led amaladaptivebehavioroccurringathighpop- to the uniquely human ability to be interested ulation densities. Hrdy reasoned that males can increase their breeding opportunities by in the thoughts and intentions of others, which killing unweaned, unrelated infants because the itself was a precursor to other unique human cessation of lactational amenorrhea ofen brings abilities, including language and well-developed females into estrus earlier than if the infants had coordination toward common goals. In 2012, the survived. Controversy erupted in response to book won the W.W.Howells Book Award and the Hrdy’s argument and led to her edited volume on J. I. Staley Prize from the School for Advanced infanticide with Glen Hausfater (1984). Te con- Research. troversy has largely subsided now that infanticide Hrdy has received many honors for her intel- has been confrmed in many species of primates lectual contributions, including being elected a and is most ofen committed by males unrelated member of the National Academy of Sciences to the infants killed, as Hrdy predicted. (1990), induction as a fellow of the California Using langurs as exemplars, Hrdy (1981) Academy of Sciences (1985), the Animal Behav- also argued that females are not the coy, passive ior Society (1990), the American Academy of creatures Darwin described, but are highly com- Arts and Sciences (1992), and the American petitive as well as cooperative with each other Philosophical Society (2011), being listed among in matters of interest to them. Hrdy described Discover Magazine’s “50 Most Important Women prime reproductive females rising and then in Science” (2001), and receiving the Human falling in rank as they got older, with similar Behavior and Evolution Society’s Lifetime Career rising and falling interest in the infants of others Award for Distinguished Contribution to Science with increasing age. Nonetheless, it was the older (2013) and the National Academy of Sciences females who fought hardest against infanticidal Award for Scientifc Reviewing (2014). males to protect the infants of their female rela- tives. She also considered female sexual behavior SEE ALSO: Alloparental Behavior; Infanticide; toward males strategic, with females actively Sexual Selection Te International Encyclopedia of Primatology.EditedbyAgustínFuentes. ©2017JohnWiley&Sons,Inc.Published2017byJohnWiley&Sons,Inc. DOI: 10.1002/9781119179313.wbprim0297 2 HRDY, SARAH BLAFFER REFERENCES Hrdy, Sarah Blafer. 2009. Mothers and Others: Te Evo- lutionary Origins of Mutual Understanding.Cam- bridge: Belknap/Harvard University Press. Hausfater, Glenn, and Sarah Blafer Hrdy, eds. 1984. Infanticide: Comparative and Evolutionary Perspec- tives.NewYork:Aldine. Hrdy, Sarah Blafer. 1977. Te Langurs of Abu: Female FURTHER READING and Male Strategies of Reproduction.Cambridge: Harvard University Press. Ellison, Peter T. 2009. “A Growing Tought: A Hrdy, Sarah Blafer. 1981. Te Woman that Never Review of Sarah Blafer Hrdy, Mothers and Others: Evolved.Cambridge:HarvardUniversityPress. Te Evolutionary Origins of Mutual Under- Hrdy, Sarah Blafer. 1999. Mother Nature: A History of standing.” Evolutionary Psychology,7:442–448. Mothers, Infants, and Natural Selection.NewYork: DOI:10.1177/147470490900700306. Pantheon..