Infant access and handling in sooty mangabeys and vervet monkeys
Access to one’s newborn infant is a commodity that can be traded for other benefits such as grooming in nonhuman primates. According to the biological market paradigm, the price paid should fluctuate with the number of newborns in the group. We investigated the grooming sessions between mothers with infants less than 3 months old and […]
Supply and demand predict male grooming of swollen females in captive chimpanzees, Pan troglodytes
The notion of a biological marketplace as a framework for explaining cooperative acts among animals is well supported. However, direct evidence for a biological market in a mating context is limited to a handful of studies. We collected data over a 3-year period to test supply/demand predictions of male grooming of swollen females according to […]