Noted smell scientist Avery Gilbert blogged about a team of Japanese scientists who tested what quantitative differences are there in the odor profiles of mice experiencing different life conditions (e.g., no bedding, fasting). What they found is that the greater the stressful life conditions, the stronger the smell of the feces. Seventeen odor compounds were identified (aldehydes, sulfides, isobutryric acid…). The ‘shelf-life’ of these compounds in feces is beyond my chemical knowledge but if the ‘stress’ evidence from feces could be operationalized some way, we would have a great way of examining ancient coprolites (from dinosaurs to humans) for evidence of stress as yet another line of evidence in reconstructing past life conditions!
**Incidentally, when my blog spell check highlighted coprolite and I looked to see what other spelling options were available, the first listed was profiterole! If you know what a coprolite is or figure it out contextually, you can better appreciate the irony!
The Smell of Evolution 