2016 in Review

And so we close 2016, having gone from Death Valley, to Chickasaw National Recreation Area, to Fort Union Trading Post, to Interstate State Park, and back home. We contemplated paracrinoids, waded through 19th century shenanigans, got locked in a hadrosaur, withstood earthquakes and volcanoes, and were swarmed with crocodiles. (And occasionally I filled space with a random dinosaur or some photos.)

And in honor of that, an interesting triangular fossil in Platteville building stone on the St. Paul campus of the U of M. A hyolith?

Club Late Ordovician

As I write this, it is about 10 degrees F below zero, with a windchill about 20 below. It's a good time to think about warmer things, like, well, equatorial Minnesota. When I work with the paleontology of the National Park Service, one thing I like to do is to compare fossil records across different parks. Several years ago, we combed through our various records and compiled a sort of database (okay, it's functionally almost nothing like a database, but that's the simplest way to describe it) on NPS paleontology. This compilation is such that now we can say, "Give us a rundown on all of our records for Middle Triassic park fossils," and the computer will do nothing because it isn't programmed to respond to verbal commands, but you can rest assured that we can very quickly find that information. It is therefore simple for me to pick out, say, the Late Ordovician records and make some thumbnail observations. I can thus present to you the exclusive Club Late Ordovician, as shown in the following map. (I could have called it Club Upper Ordovician, but it just didn't have the same ring.)

One of my famous giant captions. 1. Death Valley National Park (DEVA), California–Nevada; 2. Great Basin National Park (GRBA), Nevada; 3. Yellowstone National Park (YELL), Idaho–Montana–Wyoming; 4. Grand Teton National Park (GRTE), Wyoming; 5. Bighorn Canyon National Recreation Area (BICA), Montana–Wyoming; 6. Big Bend National Park (BIBE), Texas; 7. Chickasaw National Recreation Area (CHIC), Oklahoma; 8. Mississippi National River and Recreation Area (MISS), Minnesota; 9. Pictured Rocks National Lakeshore (PIRO), Michigan; 10. Effigy Mounds National Monument (EFMO), Iowa; 11. Buffalo National River (BUFF), Arkansas; 12. Hot Springs National Park (HOSP), Arkansas; 13. Stones River National Battlefield (STRI), Tennessee; 14. Natchez Trace Parkway (NATR), Alabama–Mississippi–Tennessee; 15. Katahdin Woods & Waters National Monument (KAWW), Maine; 16. Saratoga National Historical Park (SARA), New York; 17. Delaware Water Gap National Recreation Area (DEWA), New Jersey–Pennsylvania; 18. Chesapeake and Ohio Canal National Historical Park (CHOH), Maryland–Virginia–West Virginia; 19. Denali National Park & Preserve (DENA), Alaska. The gray blob over much of the eastern half of the US is the distribution of Late Ordovician bentonite beds as per Kolata et al. 1996 (also the source for the discussion of correlations below); the beds may also go somewhat farther to the west in the subsurface.

Fossil Crocs of the Science Museum

Although the dinosaurs get the most press, the Science Museum of Minnesota's paleontology department has a strongly diversified portfolio of ancient reptiles. In particular, champsosaurs and crocodyliforms (modern crocodilians and their closest extinct relatives) are well-represented in the collections and on exhibit. The Science Museum features mounts of four fossil crocs, each one filling different places in their ecosystems: an apex terrestrial/freshwater croc (Borealosuchus formidabilis), a large estuarine croc with elongate jaws living alongside whales (Gavialosuchus carolinensis), a medium-sized terrestrial/freshwater croc from a dinosaur-dominated setting ("Goniopholis"), and a house-pet-sized terrestrial/freshwater generalist (Wannaganosuchus brachymanus). This diversity shouldn't be too surprising. Crocodylomorphs, with around 225 million years of time on their hands, have done quite a bit of experimentation, including truly marine thalattosuchians and small, terrestrial, occasionally dinosaur-like "sphenosuchians".

Parksosaurus

For a small herbivorous dinosaur with no crest, horns, etc., Thescelosaurus has managed to sweep through a respectable number of species. There's the type species (T. neglectus), T. assiniboiensis, T. edmontonensis, T. garbanii, Bugenasaura infernalis, and the subject of today's entry, which entered science as Thescelosaurus warreni but which is better known as Parksosaurus (warreni or warrenae, depending on how you feel about far-after-the-fact emendations).

Cottage Grove Ravine Regional Park: the green rocks of home

I come from Cottage Grove, Minnesota, and in the southeast part of town there's Cottage Grove Ravine Regional Park. Up until a few weeks ago, I had no idea that there was actually exposed bedrock in the park. The only outcrops I knew of in town were a couple of pockets around the compost site, a couple of spots in Old Cottage Grove, and some outcrops of the St. Peter Sandstone up high on Camel's Hump overlooking Highway 61 (there's a little park up on the crest of the hill now, with a good view across the valley, by the way). Obviously, I had to have a look around.

The rocks, counterintuitively, are the green things in this photo.

Meanwhile, over at the Science Museum

Recently, the Science Museum of Minnesota reconfigured the exhibit space for the paleontology in conjunction with changes to other parts of the floorplan. I don't recall if the previous configuration had been stable all the way back to the 2005 Society of Vertebrate Paleontology meeting (I do know a nice Goniopholis was added around 2010), but where once it had looked like this:

January 2013; watch the space on the left of the Stegosaurus.

Now it looks like this:

That Triceratops wasn't there before...

Two major components, the Morrison dinosaurs and the Wannagan Creek fossils, are still where they had been. The major differences are in the section on the east, with the removal of some visible lab space and some more portable specimens, most notably a sort of "circus ring" of small- to medium-sized Cenozoic animals, mostly mammals.

And a tortoise.

 
In their place are a group of mounts from the Oligocene of coastal South Carolina (transferred from the floor above) and the well-known Science Museum Triceratops, relocated from another part of the floor. A Triceratops going mobile is just not a common occurrence these days, so naturally the event received some local coverage. A few other pieces were also rearranged, including the Xiphactinus lurking behind the Stegosaurus in the first picture above, some of the remaining mammals, the Goniopholis, and your friend and mine Thescelosaurus. Green River Formation fossils also get more prominence.

Triceratops (who also answers to "Fafner") plus overhead pterosaur pal in foreground. The South Carolina mounts are visible in the background by the neon; you can see a whale, pseudodontorn,and sea turtle in the air above the hind end of a mostly obscured croc (next photo).

Estuarine croc Gavialosuchus (or Thecachampsa) carolinensis has an honest face. I was glad that space was made for the South Carolina mounts; many places have Morrison dinosaurs, but you can't see Wannagan Creek and South Carolina fossils just anywhere.

On the one hand, the Triceratops no longer has its niche with the backdrop:

On the other hand, you can now walk around the whole mount, if for example you should want to look at the legs and hips:

Like this, perhaps.

I may cover some of these exhibits in a bit more detail in the coming weeks, given the approaching busy holidays. Till then, though, Allosaurus bids you all adieu:

Some thoughts on St. Anthony Falls

If you're familiar with the history of Minneapolis, you probably know that beneath what we now call St. Anthony Falls are the remains of the natural St. Anthony Falls. The real falls went kaput quite a while ago; October 5, 1869, to be precise. The creation of the Hennepin Island tunnel is usually named as the culprit, but after seeing this photo I am beginning to suspect suicide. For various reasons, the presence of a waterfall or a reasonable facsimile thereof was required, so with the aid of the Army Corps of Engineers, the body was embalmed in wood and cement, and propped up in its accustomed place.

Granted, it's a pretty darn good job of embalming.