My early work explored the mechanisms and criteria by which female rhesus macaques chose mates. In 1990, Dr. Susan Perry and I began observations of wild white-faced capuchin monkeys at Lomas Barbudal Biological Reserve, Costa Rica. Research at this site is ongoing. Among our more striking findings, we have shown the existence of locally variable, culturally transmitted social practices such as mutual hand-sniffing.  Dr. Perry and I published a popular book about the study, Manipulative Monkeys, in 2008.  For information about working as a field assistant at Lomas Barbudal, see Dr. Perry’s website.