One headline reads “Giant Prehistoric Toilet Found” another refers to the discovery of an ancient latrine. Don’t know how I missed those a few weeks ago. Surely had I seen that headline I would have had to clicked on it to find out what that was all about. The actual title, The oldest known communal latrines provide evidence of gregarism in Triassic megaherbivores, of the research paper from which the popular press picked up the story may not sound so interesting to you. But for me, the title told me they were talking fossils which meant this was a story about fossil poop, or, to sound more scientific, coprolites. If you have followed this blog you know that I have a fascination with coprolites and have written about what we can learn fro them before (most recently – Dino Doo Doo and the Genesis Flood).
This particular fossil find is really nothing all that special to geologists and paleontologists as coprolites, fossil dung just in case you forgot, are very common in the fossil record. In this case the notable thing is the quantity of coprolites and the spatial context they are found. 10s of thousands of rock nodules were found eroding from the side of hills in Argentina. A close examination of these nodules revealed that they are preserved feces of a large extinct herbivorous reptile. That an herbivore was the culprit can be inferred from the fact that each fossil nodule was observed to be composed exclusively of preserved plant remains rather than small bones which are found in carnivore or omnivore (plant and animal feeders) feces.
How is this evidence of a common latrine? The density of feces (around 90 per square meter covering 900 square meters) was the first clue but then closer inspection of this poo-pile revealed that the feces were not all deposited at the same time and not all by the same animal. They are different sizes and some were more degraded than others when they were finally preserved. The scientists involved interpret this site as evidence that the herbivore that deposited all this material lived in a community structure where they had a community area where they all did their business.
So what animal was responsible for these 10s of thousands of coprolites. It didn’t take much detective work to find the likely culprit. There are thousands of bones in the same rock formation that these coprolites came from that all belong to the same animal. That animal is an extinct form of large mammal-like reptile that reached up to 8 feet long. Based on skeletons the picture to the right represents an artistic rendering of what this reptile might have looked like. Notably, this type of communal latrine is well known in large animals today such as rhinos but not for reptiles. Obviously, no one was there to witness these animals deposit these plant nodules but it is certainly the most reasonable explanation. The evidence they left behind is our witness.
Large piles of poo – yet another challenge to the creationist’ paradigm.
Here is where I ask a familiar question for those that have read my previous articles: how does a young earth creationists (YECs) interpret this fossil find? I expect that many lay Christians that believe the Earth must be young can read a story like this and they may see the dates (240 million years old) and gloss right over them and just assume that the dates are wrong. But they probably would readily accept that some sort of large herbivorous reptile really did exist and that these really are feces but other than that they probably wouldn’t consider the larger question of how this fossil site fits into the Earth’s history.
The geological context of where these fossils were found is what I found most interesting about this fossil find and why I chose to write about it here. Simply put, most of these coprolites where found eroding from a hill that is part of a larger set of formations that include thousands of feet of rock layers. All of the coprolites where found in the same layers of rock from multiple locations many miles apart. The conventional geological explanation would be that 200 million years ago this are of Argentina was a flatter area with wetlands where groups of these reptiles lived. Large piles of dung built up but would have also been decaying very rapidly but a volcanic eruption covered the whole area with a thick layer of ash that preserved the dung and many of the animals. More layers of ash and then other sediments eventually were deposited here by additional volcanic activity. Much later erosion took place forming the mountain and hills there today and that erosion brought these fossils back to the surface.
Young earth creationists propose an alternative history. In their history a massive global flood deposited 10s of thousands of feet of sediments in this area over a period of a few days to maybe a few months. In the past 4000 year erosion has then sculpted the rocks into these mountains and hills. Therefore, these flood geology theories of YECs would undoubtedly view the rock formations from which these fossils were found as having formed right in the middle of a chaotic global flood only 4-6 thousand years ago.
So how does a group of strange-looking 8-foot long reptiles survive the initial stages of a cataclysmic global flood in which 15,000 feet of sediments have already been deposited below where they gathered together? Even if they were running or swimming around during the flood and managed to find their way onto a small piece of land between waves how come these feces appear to have aged before being preserved (many show desiccation cracks as if they dried out before they were preserved)? Also, how does a pile of loose digested plant material survive the next huge wave of water bringing sediments in to cover them up. In this case these piles of feces look to have been preserved by a layer of volcanic ash being dumped on them. How does that happen in the middle of a global flood? We could go on and on showing many pieces of data that do not fit logically into the YEC view of Earth’s history. These are the same problems that we have seen with dinosaur nests and footprints (see figure below) that are located right in the middle of layers of rock presumably all laid down within hours or weeks of one another (see: Fossil Eggs, Nests, Flood and Stressed Pregnant Dinosaurs and Juvenile Dinosaur Fossils in a Nest: Testimony to Rapid Burial but Not in a Flood).
I mention research like this on coprolites because it illustrates, all too well, the difficulties YEC flood geology to explain fossils and the geological record. Rather, viewed within their geological context the specifics characteristics of these fossils finds are most easily interpreted as supporting a world of great age. Once one is familiar with the context of the data it is easy to recognize YEC explanations as simply being ad-hoc attempts to explain away difficulties. Anyone who studies or reads the paleontological literature is going to be confronted with thousands of similar data to that I have presented here and realize that flood geology provides a wholly inadequate interpretive framework for understanding that data.
The oldest known communal latrines provide evidence of gregarism in Triassic megaherbivores. Fiorelli et al. 2013. Nature, Scientific Reports 3, Article number 3348. doi:10.1038/srep0334