Evolutionary Perspectives on Permanent Breast Enlargement in Human Females

Sexual selection and the evolution of behavior, morphology, neuroanatomy and genes in humans and other primates

“…It is thought that sexual signaling moved to the front as our hominid ancestor assumed an erect posture and bipedalism (Gallup, 1982;Mascia-Lees et al, 1986). …”

Adolescent exaggeration in female catarrhine primates

“…CANT, 1981;GALLUP, 1982;MASCIA-LEES et al, 1986;MORRIS, 1967;SHORT, 1976) as unique to humans (Homo sapiens) are more conspicuous in adolescent and nulliparous females than among cycling multiparas (KATCH et al, 1980). Human adolescent females resemble pregnant adults in their breast development, while non-human primate females show no breast development in adolescence.…”

“…The extent to which evolutionary biologists attempt to find an adaptive explanation for biological phenomena has been criticized (HAMILTON, 1984;LEWONTIN & GOULD, 1979;MASCIA-LEES et al, 1986;ROWELL, 1979). MASCIA-LEES et al (1986), for example, believe that enlarged breasts in humans are an incidental by-product of unusually large amounts of placental lactogen.…”

“…MASCIA-LEES et al (1986), for example, believe that enlarged breasts in humans are an incidental by-product of unusually large amounts of placental lactogen. Adolescence itself, described by many as an adaptation that increases fitness through learning (e.g.…”

The nubility hypothesis

“…Some have argued that natural selection for fat stores to support gestation and lactation is sufficient to explain the enlarged human breast (Caro and Sellen 1990;Mascia-Lees et al 1986). The same would apply to hips since fat there is used to support lactation (Rebuffe-Scrive et al 1985).…”