In South and Southeast Asia, monkeys and people are synanthropic. It sounds complicated, but all this means is that they share the same ecological niche.
Some species, like macaques, are very similar in behavior, diet, and even anatomical composition to their human neighbors. Now, some scientists are taking advantage of these similarities by using macaques as sentinels for urban toxicity.
Dr. Lisa Jones-Engel, a research scientist at the National Primate Research Center at the University of Washington in Seattle and senior author of the study, explained that "macaques are similar to humans anatomically, physiologically and behaviorally." Dr. Gregory Engel, a physician and lead author of the study, added that macaques "are also similar in their response to toxic exposures."
By taking hair samples from three separate groups of free-ranging macaques based around the Swayambhu temple in Kathmandu, Nepal, researchers established that levels of toxins, especially lead, were higher in younger individuals than older members of the groups.
This research study is published on Treehugger.com, a discovery company.