Abstract
I explored variation in maternal investment strategies. I investigated whether infant sex, food availability, female feeding competition or infanticide risk influenced lactation length, the context of nursing cessation and the extent to which mothers can simultaneously gestate and lactate in a wild colobine. I combined long-term records and new observations of Colobus vellerosus. I extracted 40 nursing cessations, 13 exact lactation lengths, and 26 durations between nursing cessation and subsequent births. The independent variables did not influence lactation length, and nursing cessation did not differ by infant sex or cluster with food availability. Lactation length, maternal age, infant sex, infanticide risk, feeding competition, and potential infant handlers available did not influence the duration length to the next birth. This study eliminated some potential variables that may have explained nursing cessation and lactation length variation in our species, although it is evident that other underlying factor(s) are causing the variation.
