Scientists have observed elevated stress hormones and reduced testosterone in the fur of dancing macaques in Pakistan. The findings were reported in Applied Animal Behavior Science.
The rhesus macaque is a tree of the monkey family that can weigh up to eight kilograms. Native to Asia and parts of the Middle East, these animals are highly trainable. In Pakistan and other regions, some are taught street tricks such as dancing. During performances, handlers keep the animals on a leash while volunteers and passersby are asked for donations.
A new study from the University of Glasgow compared cortisol levels, a key stress marker, in fifty macaques performing on Islamabad streets with those in seventy-seven free living monkeys housed in a sanctuary in Florida. Monkeys living in captivity showed higher cortisol levels, a sign of ongoing stress. In the same group, testosterone levels averaged fifty-five percent lower than those of the sanctuary monkeys, all of whom are males. The difference in hormone profiles suggests the dancing animals may experience a sense of submission and perceive their trainers as dominant figures in their daily lives.
Earlier research has noted related concerns, including observations that certain bat species have not been seen in the wild for over a century in some regions.