Perinatal life history traits in New World monkeys

Abstract

Gestation length, neonatal and maternal body weight, and neonatal and adult brain weight data were collected for New World monkeys in an attempt to establish typical patterns of perinatal life history. This study attempts to illuminate the most accurate values from the available data, which suggest that gestation length and prenatal growth rate are broadly conserved in relation to maternal size in New World monkeys. Exceptions to the patterns evident in the data point to derivations in life history strategies. In particular, this study suggests that the extended gestation length of callitrichines is a function of minimum viable neonate size and not exclusively energy minimization associated with simultaneous lactation. Cebus is shown to undergo more postnatal brain growth relative to other New World monkeys, but not as much as previously believed. Alouatta is shown to be relatively small brained at birth as well as in adulthood. Saimiri is shown to present the most unusual package of perinatal life history traits, in which precocial neonates are gestated for a relatively long time and at a slightly faster growth rate than is typical for New World monkeys. © 1996 Wiley-Liss, Inc.