Book Sections/Chapters
Abstract:
At least seven cases of infanticide by
females other than the mother have been
observed in wild groups of common marmosets
(Callithrix jacchus), with several more
cases described for captive groups.
Infanticide by females other than the mother
has not, however, been documented for wild
groups of other callitrichine species. Why
might such overt aggression toward infants
occur in one species and not others? In the
common marmoset, a variety of social,
reproductive and ecological
characteristics – including short inter-
birth intervals (and the resulting potential
for overlapping of pregnancies and births),
habitat saturation, small home ranges, and
low cost of infant care (including decreased
travel costs and short dependency periods
compared to other callitrichines) – may
contribute to an increased likelihood of two
breeding females being present in a group,
which in turn gives rise to the potential
for competition between breeding females and
ultimately to infanticide. These conditions
are less common in wild groups of most other
callitrichines species. All callitrichines
balance the need for cooperative care of
young with the reproductive competition that
results from limited reproductive
opportunities; however ecological and social
conditions appear to tip the balance toward
infanticide more frequently in common
marmosets than in other callitrichine
species.