The influence of the steepness of dominance hierarchies on reciprocity and interchange in captive groups of bonobos (Pan paniscus)
Biological market models explain variability in reciprocity and interchange between groups. In groups with a shallow dominance gradient, grooming will be mostly exchanged for itself (i.e. exchange will occur). In groups with steep dominance hierarchies, interchange is expected: individuals will groom higher ranking individuals to get access to limited resources or commodities such as support […]
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 […]