Editing Sarah Blaffer Hrdy (section)

===''Mother Nature''===
In 1999, Hrdy published ''Mother Nature: A history of mothers, infants, and natural selection''. She examines "human [[mother]]s and [[infant]]s in a broader comparative and [[evolution]]ary framework,"<ref>{{cite book |last1=Hrdy |first1=Sarah Blaffer |title=Mother Nature: A History of Mothers, Infants and Natural Selection |url=https://archive.org/details/mothernaturehist00hrdy |url-access=registration |date=1999 |publisher=Pantheon |location=New York |page=[https://archive.org/details/mothernaturehist00hrdy/page/117 117]|isbn=9780679442653 }}</ref> informing and forming views of mother-infant interdependence from a sociobiological viewpoint.<ref name="Melvin">{{cite news |last1=Konner |first1=Melvin |title=How Childhood Has Evolved |url=https://www.chronicle.com/article/How-Childhood-Has-Evolved/65401 |access-date=February 11, 2019 |work=The Chronicle of Higher Education |date=May 9, 2010}}</ref>

In it she described the trade-offs between subsistence and reproduction that mothers have to juggle, sometimes leading to difficult maternal investment "decisions".<ref name="Angier">{{cite news|last1=Angier |first1=Natalie |title=Scientist at Work: Sarah Blaffer Hrdy; Primate Expert Explores Motherhood's Brutal Side |url=https://www.nytimes.com/2000/02/08/science/scientist-work-sarah-blaffer-hrdy-primate-expert-explores-motherhood-s-brutal.html |access-date=August 30, 2023 |work=The New York Times |date=February 8, 2000}}</ref><ref name="Hurtado">{{cite journal |last1=Hurtado |first1=A. M. |title=ANTHROPOLOGY:Origins of Trade-offs in Maternal Care |journal=Science |date=January 21, 2000 |volume=287 |issue=5452 |pages=433–434 |doi=10.1126/science.287.5452.433 |s2cid=142762955 }}</ref> Rather than assuming automatic maternal responses, Hrdy views "maternal instinct" as a process unfolding in line with local conditions and cues from the infant.<ref name="O'Grady">{{cite news |last1=O'Grady |first1=Kathleen |title=Review: Mother Nature, by Sarah Blaffer Hrdy |url=https://www.theglobeandmail.com/arts/books-and-media/review-mother-nature-by-sarah-blaffer-hrdy/article4356989/ |access-date=February 11, 2019 |work=The Globe and Mail |date=January 22, 2000}}</ref> She stresses that an ape producing such costly offspring as humans could not have evolved unless mothers had had help from others, and had been what sociobiologists term [[cooperative breeders]].<ref name="McGrew">{{cite news |last1=McGrew |first1=William |title=With a Little Help from My Friends |url=https://www.americanscientist.org/article/with-a-little-help-from-my-friends |access-date=February 11, 2019 |work=American Scientist}}</ref>

Humans evolved to rely on assistance from group members other than the mother, using the term "allomother" she first used in her 1975 PhD thesis describing infant-sharing in langurs (from the Greek "allo" for "other than") to refer to any female or male other than the mother who helps to care for an infant. In the human case allomothers are often a father, grandparents, or older siblings, as well as genetically unrelated helpers, including nannies, and child care groups, who help care for and provision infants, freeing the mother to meet her own needs and in the case of early humans, breed again sooner.<ref name="McGrew"/>