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Coprolite, Or This Dung Is For You

by Brett Whitenack

This article deals with a subject that some people find rather offensive and vulgar. Others find it quite amusing. There are few people who find it extremely fascinating and worthy of study. What could exhibit so many varied reactions? I'm speaking of petrified poop, Dina doo, fossilized, er, ah, pardon me. I don't wish to offend anyone reading this article. I'm talking of the much maligned, the lowly, the humble, coprolite.

"What is coprolite?" I'm glad you asked.

Coprolites are fossilized feces, dung, scat! Yes, ladies and gentlemen, coprolites are the extruded remains of meals that prehistoric animals deposited.

"But how can these be fossils?" The oldest coprolites date some 400 million years ago from the Silurian Period and are from fish. The most recent coprolites are from Ice Age animals and may still contain much original organic matter-a fact your nose may discover if the coprolite gets wet!

Coprolites form just like any other fossil.

They must have been buried rapidly in fine grain sediment and kept away from biological agents that could destroy them, such as scavengers or the environment. Ground water percolating through a potential fossil must be of a correct nature, not too acidic, and full of minerals that can replace the soft materials. Of course, these requirements only pertain to those coprolites that are petrified. Some younger coprolites have been found desiccated in southwest caves and date from the last Ice Age.

Being of a soft nature, dung doesn't preserve as readily as bones, teeth, or scales. However, coprolites aren't exceedingly rare by any means, and you too can easily own a piece of this most interesting geologic wonder. Given its detached nature, a coprolite can't be identified with the exact species of animal that left it. In some instances, coprolites from sharks can be determined from the grooves and markings on them, as shark have distinctive spiral valves in their intestines.

By studying the makeup of a coprolite, or can tell if the animal was a carnivore (meat eater) or herbivore (plant. eater). It is interesting to note that carnivorous coprolites are more readily preserved due to their higher mineral content the bones the animal ate.

Other things that can be told by studying coprolites are such things as the paleoenvironment where the animal lived, other organisms that were associated with it, and how this animal interacted with its surroundings.

The name coprolite has two sources as to how they were named: one fact, the other fiction. During the great "bone wars" of Professor O.C. Marsh and Professor Edward Drinker Cope during the latter years of the last century, Professor Cope men apparently stole an Allosaur skeleton from a quarry of Professor Marsh's. This incensed Professor Marsh, and to "immortalize" Professor Cope, Professor Marsh named the fossilized fecal remains "coprolites" to get even with his arch enemy. a quaint legend, but entirely untrue.

The name coprolite has more humble and mundane origins. The English geologist, William Buckland, deduced their true nature and named them from the Greek kopros, "dung," and lithos, "stone," literally dungstone. Buckland thought the would be important in agriculture as a source of fertilizer due to their high calcium phosphate content.

In addition to the information they can tell us, coprolites have become fashionable as a cutting material. Believe it or not, some coprolites exhibit beautiful colors when cut and polished. It has been said that the reds are from the meat the animal ate, brown from nuts and seeds, green from plant material, and black from the juices of blackberries Actually, these colors come from the minerals deposited by ground water that percolated through them as they were fossilized.

via BEMS Tumbler 04/07; West Seattle Petroglyphs, 8/06; via Carny Hound, 3/06; via The Southwest Gem, 2/04; via Stoney Statements. 1104: from The Stone Chippper 5/03