The archaeological record is full of dog poop

April 22, 2020 10:00 AM

"Such ancient feces can hang around for thousands of years, even retaining their original shape and color. And archaeologists can typically differentiate human from animal poop, based on size and other attributes. But doggy dung, it turns out, is remarkably hard to distinguish from the human kind -- something that can stump researchers trying to reconstruct what ancient people ate. [...] Now, Warinner and colleagues have developed a tool based on artificial intelligence that they claim can accurately tell human and dog "paleofeces" apart. And after analyzing more than a dozen samples spanning thousands of years, they've come to a surprising conclusion: The archaeological record is full of dog poop." (Science)

Archaeologists now have a handy new tool for analyzing paleo poop (Ars Technica)

The challenge of determining whether paleofeces and coprolites are of human or animal origin dates back to the 1970s. Usually, only those samples found with human skeletons or mummies could be designated as being of human origin with any certainty. Exceptions could be made for samples found in ancient latrines, since they are highly likely to be human; samples found in trash deposits, however, are more ambiguous.

Subsequent work to document the morphology of mammal feces has made it easier to separate human from animal samples, since there are enough differences to make such distinctions. The exception is dog poo, which bears a strikingly close resemblance to human feces in both size and shape, is frequently found at the same archaeological sites, and has a similar composition. And frankly, some ancient societies routinely ate dog meat, while dogs are known to nibble on human feces. So DNA from both can be present in the same archaeological sample.

The origin of feces: CoproID reliably predicts sources of ancient poop (press release)

But Warinner also expects coproID to have broader applications, especially in the fields of forensics, ecology, and microbiome sciences.

The ability to accurately identify the source of archaeological feces enables the direct investigation of changes in the structure and function of the human gut microbiome throughout time, which researchers hope will provide insights into food intolerances and a host of other issues in human health. "Identifying human coprolites should be the first step for ancient human microbiome analysis," says the study's first author, Maxime Borry.

CoproID predicts the source of coprolites and paleofeces using microbiome composition and host DNA content (PeerJ full study text)

posted by not_the_water (7 comments total)

Sometime in the last decade someone got the funding to do DNA sampling on lots of feces in wild regions of the Rockies. I think they were originally studying range and interbreeding among several medium-sized predators.

The first thing they found out, though, was that the morphology of the scat was useless for telling you whether it came from a felid or canid. Useless! Which they had to recheck over and over because it’s been such a sibboleth for so long. (Really interesting quiet noises in the audience as the data came up on screen.)
posted by clew at 10:41 AM on April 22, 2020 [3 favorites]

So... the brightest minds have come up with a Stool Tool!
posted by IndelibleUnderpants at 11:20 AM on April 22, 2020 [2 favorites]

If I was this researcher my preferred title would be Poop Snoop. Fascinating article.
posted by nestor_makhno at 11:29 AM on April 22, 2020 [2 favorites]

conclusion: The archaeological record is full of dog poop.

*walks around the block avoiding poop* - can confirm its not just the archaeological record....
posted by inflatablekiwi at 12:34 PM on April 22, 2020 [1 favorite]

The Burke Museum at the University of Washington has a coprolite in its Fossil hall. Its location is the most common question asked by grade school age boys. Go figure.
posted by y2karl at 2:10 PM on April 22, 2020

Ancient dogs, doin archaeologists a heckin bamboozle
posted by Sparky Buttons at 5:11 AM on April 23, 2020 [1 favorite]

I know the articles dont mention or even imply this, but my first thought was that this might mean the Paleo diet craze may have been based on what dogs were eating, since poop analysis is our main way to determine diet.
posted by ananci at 9:37 AM on April 23, 2020 [2 favorites]