Platteville fossils in Cottage Grove

Cottage Grove, Minnesota is not noted as a geological wonderland, although Cottage Grove Ravine Regional Park certainly has its charms if you are willing to put in a little shoe leather. There are also scattered outcrops of the St. Peter Sandstone. However, persistence may be rewarded. Back in November I came across a couple of small fossiliferous blocks in town.

The first thing to do was to figure out the stratigraphy. The rocks were not in situ, but they were not heavily worn, either; in other words, they hadn't fallen off a glacier. The rocks of the area included outcrops of the St. Peter, and initially I wondered if I'd stumbled on a stray carbonate lens in the upper part of the formation. A rather more likely identity, though, is as erosional lag from the Platteville. In fact, the rocks look not unlike the occasional poorly dolomitized intervals I've seen in the Mifflin, and the fossils are certainly appropriate.

A (relatively) large brachiopod shell, among numerous teeny-tiny crinoid columnals and other fragments.

They include a mix of the BBC (brachiopods, bryozoans, and crinoids). There is also one object that looks like a whorl of a small Phragmolites sticking out. A couple of notable features include the small size of the fossils, particularly the crinoids; and the density of small fossil fragments and elements.

A different relatively large brachiopod shell among numerous teeny-tiny crinoid columnals and other fragments; note some nice bryozoan fragments on the left.

A hash of tiny fragments.

See what looks like tire tread near the center? That's what reminds me of Phragmolites.

Before we sign off for the year, I'd like to note that for some reason, over the past few weeks the "Fossil Felids of the National Park Service" post has been attracting a few dozen views a week. (Considering I don't do any external promotion and have reduced my social media presence from "negligible" to "zero", this is a lot!) I have no idea where this is coming from (probably picked up by a group somewhere that doesn't register in stats) or why it should have attracted interest (well, felines, I suppose, or maybe Pleistocene megafauna or predators in general), but I'm not complaining! Someone who actually knows something about cats could probably make an interesting and well-attended series like "Your Friends The Titanosaurs".

Historical miscellany, including O.P. Hay, Whitesburg fossils, and the "Scientific Swindler"

A selection of brief historical items for your approval:

If you're like me and have an interest in Pleistocene megafauna, you've probably spent some time tooling around Neotoma and NeoMap (which unfortunately doesn't work anymore), as well as the Paleobiology Database. (In fact, it's kind of necessary to use multiple databases because they don't all have the same information.) Compiling datasets like these can be a thankless job. The actual business of making one is time-consuming and requires access to a vast array of scholarly (and less-scholarly) resources. To make it more efficient, you can bring in a crowd to contribute smaller parts, with the obvious trade-off that quality control is harder to maintain (and participants may disagree strongly about things like taxonomy). Synthesizing material doesn't get as much respect as producing new information. It takes a certain kind of personality to compile these things (I ain't about to name any characteristics, because I'd just be pointing in the mirror). You also want to be very, very sure you get it right, because sometimes people just accept the compendium and forget to check the original sources.

There are many state-level compendia of Pleistocene finds for the US, and at least one excellent regional resource (for the southwestern US and northwestern Mexico). They don't exist for every state, though, and unfortunately many are in the neighborhood of a century old. (If anyone wants a reference for a specific state, I can see what I can do.) By far the most monumental of these monuments to industry are the three volumes produced by Oliver Perry Hay in the 1920s, the "Vertebrated Animals of North America" series. Hay was no stranger to compiling information, with two bibliographies on North American fossil vertebrates under his belt. For people used to the Internet, it takes a moment to realize the staggering amount of work that must have gone into these books, which cover the entire continental US and Canada from the beginning of scientific documentation of fossils to his own day. Even granting that the field was smaller and there were fewer publications, the number of references he must have seen must have been immense (to say nothing of the work of tracking them down). That there are occasional errors and omissions is not the wonder; the wonder is that these books exist at all. I've included citations to several of his volumes at the end; all are freely available for download at the moment except the third volume of the "Vertebrated Animals" series, but even this one can be read online.

I've referred to Hay's works many times in my own work; on this occasion he came to mind because I happened upon a seemingly forgotten Pleistocene fauna from northeastern Tennessee that he described with five other Pleistocene collections (Hay 1920). The Smithsonian had received a collection made by USGS geologist Ira Sayles in 1885 from "one mile north of Whitesburg, Hamblen Co., Tenn." Matrix with the bones indicated that the site had once been a cave, now eroded. Hay recognized twenty species from the fauna, eight of which were extinct and three of which were new species (turtle Testudo munda, tapir Tapirus tennesseae, and deer Sangamona fugitiva; none of them is considered valid anymore, which tends to happen with supposed new Pleistocene species in North America, but Sangamona fugitiva is a nice name). What gets me is that there's never been any real follow-up outside of Hay's own 1923 compendium of Pleistocene sites. The actual location is still unknown to this day, if it could even be rediscovered. That's one of the things that I love about these compilations and databases: there's a story behind every site, even if it's not known in detail.

Finally, I wanted to mention a historical story I came across this spring while working on another topic. It is a story of fraud in science, but not the usual "unscrupulous scientist scoops another worker or commits a nefarious action against a graduate student." It goes like this: from the mid-1880s to the early 1890s there was a man operating in the Midwest and Northeast who would use false pretenses to swindle scientific books, equipment, and fossils from unsuspecting geologists, to sell them. Among his methods were pretending to be deaf-mute and stealing the identities of other geologists, including such luminaries as Leo Lesqueroux and Charles Walcott. His trail can be followed by a series of letters in scientific journals reporting encounters and giving warnings, but he was able to operate for years. The icing on the cake is that he was actually a competent paleontologist, as attested by several of the victims. It's a fascinating story worthy of a journal article, and fortunately we have what amounts to one in a lengthy blog post, so if you're looking for something to read, it's well worth the time!

References

Hay, O. P. 1902. Bibliography and catalogue of the vertebrata of North America. U.S. Geological Survey, Washington, D.C. Bulletin 179.

Hay, O. P. 1908. The fossil turtles of North America. Carnegie Institution of Washington Publication 75.

Hay, O. P. 1914. The Pleistocene mammals of Iowa. Iowa Geological Survey Annual Report 23(1):1–662.

Hay, O. P. 1920. Descriptions of some Pleistocene vertebrates found in the United States. Proceedings of the United States National Museum 58:83–146.

Hay, O. P. 1923. The Pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian provinces east of longitude 95°. Carnegie Institution of Washington Publication 322.

Hay, O. P. 1924. The Pleistocene of the middle region of North America and its vertebrated animals. Carnegie Institute of Washington Publication 322A.

Hay, O. P. 1927. The Pleistocene of the western region of North America and its vertebrated animals. Carnegie Institute of Washington Publication 322B.

Hay, O. P. 1929. Second bibliography and catalogue of the fossil vertebrata of North America, volumes I and II. Carnegie Institution of Washington Publication 390.