Readers, be forewarned: this blog considers a topic of somewhat graphic depiction. It is a part of our daily lives, although many prefer to ignore this fact in favor of a more modest self-portrayal. After spending a few moments on the beach at Gombe, watching the reflection of a palm tree move languidly against the ripples of clear and perfect water as the sun sets over the Congo, I can understand the sensibility of turning a blind eye to the unpleasant when there are more beautiful sights to behold. However there is something to be said for examining all aspects of life, even the parts that we can’t immediately appreciate. Around every turn is something disagreeable by convention, lurking with unsung value and waiting to be uncovered. For me, that something is excrement. And no, that’s not a metaphor for tough luck; my current existence is deeply embroiled in exploring the intrinsic value of fecal matter.
If eyes are the window into the soul, fecal material is the window into the body. Almost everything you could ever wish to know about an individual can be discovered by examining his/her waste including diet and nutrition, parasite load, and genetic information. This capacity extends to just about every member of the mammalian community, from horses to hyrax and even to humans . At Gombe, collecting fecal samples from the chimpanzees is an important part of data collection. Every day we trudge into the forest with several small vials and the hope of being at the right place at the right time when one of our chimps decides to answer nature’s call. Vital to the advancement of science? Yes. A pleasant experience? Not exactly. Collecting samples requires keeping a vigilant watch on the rear end of your subject, cheering on any movement and praying that the resulting package doesn’t drop clear off the edge of a cliff, because quite frankly, we’d probably dive right after it. Some days I even collect a little extra by tripping down a hill and falling right directly into one of my “samples”.
For me, these samples represent the careful monitoring of stress levels. Individuals express stress in varying amounts based on factors like dominance rank and competition. When a chimpanzee experiences anxiety or tension from its external environment, glands within the endocrine system emit a steroid hormone called cortisol that courses through the body . Researchers can extract these levels from a variety of mediums including saliva, blood, urine and feces. We collect feces and urine because these procedures are non-invasive and they go mostly unnoticed by the chimpanzees. Save for the occasional glance around the canopy, reminiscent of a man in search of a good magazine before the deed, I am always impressed by their complete lack of stage-fright. We wait, they go, and within a moment we have a day’s worth of physiological data to add to the books. The crux of my research relies on these samples. Stress is one way of telling the body that it needs to react, and it may be an important component to how chimpanzees learn to navigate their social environments.
It’s not a glamorous existence, but it’s well worth the trouble. Back at the field lab, I turn my samples from waste into information. Via a process of extraction that involves lots of alcohol (for the samples, not me), centrifuging, and Janis Joplin (for me, not the samples), the feces is distilled down to nothing but hormones that can be transported back to the United States for analysis. Unfortunately the stench never quite leaves the test tubes, resulting in very silly exchanges with whomever has the misfortune of sitting next to me on my airplane ride home. In those moments, the most valuable tools in my scientific repertoire are a quick lesson in physiology, and a whole lot of self-deprecating humor.
 Creel et al. 2013. The ecology of stress: effects of the social environment. Functional Ecology. 27, 66–80.
 Sapolsky 2002. Endocrinology of the stress-response. In: Behavioral Endocrinology. Cambridge, MA, U.S.A: MIT Press, 409–450.