Tending:

D. C. Geary, M. V. Flinn:

"Tending is a form of parental investment. The nature and extent of this investment by one or both sexes strongly influences the dynamics of intersexual and intrasexual relationships, termed sexual selection (Andersson, 1994; Darwin, 1871; Trivers, 1972; Williams, 1966). Species in which females provide the majority of parental effort, such as chimpanzees (Pan troglodytes) and lions (Panthera leo), are characterized by intense male–male competition for access to females or for control of the resources (e.g., breeding territory) females need to raise their offspring. In these species, female tending and male fighting are salient features of reproductive dynamics. The reverse situation occurs in species in which males provide the majority of parental effort, such as red-necked phalaropes (Phalaropus lobatus), where sexual selection involves female–female competition over resources provided by males."

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"Men’s tending creates a more uniquely human form of female–female competition; that is, competition for high-quality men who are able and are willing to invest their resources in the woman and her children (Buss, 1994; Gaulin & Boster, 1990)."