Sunday, October 22, 2017

Sunday morning Decorah fossils

I've recently made a small collection of Decorah Shale pieces from spoil piles at a construction site. Most of them will go to other people and groups for use in education, but while I've got them I'm certainly going to take the opportunity to photograph them. Incidentally, construction can be a good source of fossils in the Twin Cities, if you don't mind disruption of the original stratigraphic context (which tends to happen anyway with the Decorah around here). Of course, as always, you'll want to ask for permission, and it's advisable to make collections when someone is working there, so you aren't mistaken for a trespasser or other nefarious sort.

Sunday, October 8, 2017

Compact Thescelosaurus Year Two

It's that time of year again, with National Fossil Day just around the corner (Wednesday the 11th) and the anniversary of the original Thescelosaurus just behind us (Saturday the 7th). The Compact Thescelosaurus is up for its second birthday, and this time I have something slightly more ambitious to add than choristoderes, as nice as they are (you may be unsurprised to learn that none of the entries in the "Updates" sheet were specifically for choristoderes). This year the pterosaurs join on their own sheet. The rules of the sheet are the same as for the other taxonomic sheets, except there's one more classification column. As it is, the classification columns are still kind of a kludge, but I haven't figured out a better way to handle the various nested clades.

Had to lie on my back on the Science Museum lobby floor to get that.

Sunday, October 1, 2017

Nanosaurus agilis: the smallest dinosaur you've never heard of (and for good reason)

Many millions of years ago, in a time that we would call the Jurassic and in a place we would call Colorado, small bipedal herbivorous dinosaurs frolicked and otherwise did things appropriate to small bipedal herbivorous dinosaurs. In their time, they died and a very, very few were selected by taphonomy to be fossilized. Of that tiny number, an even smaller subset have happened to be exposed at the surface at the right time and place to be found by a similarly tiny number of human beings who were specifically looking for such things. Having been found, their remains were sent off to be studied by another tiny number of people who had a lot of things on their minds, living in a world that has had little use for small bipedal herbivorous dinosaurs except as props to show off the (speculated) abilities of small bipedal carnivorous dinosaurs. It's not really that surprising that some of them have fallen through the cracks. Then there's Nanosaurus agilis.

Sunday, September 24, 2017

Life on Mill Street

We held another Cambrian hike at Interstate State Park on Saturday, and I thought it would be a good time to revisit some ground we covered in June of 2016. Specifically, at that time I glossed over the fossils of the Mill Street Conglomerate, but they're worth another look.

Sunday, September 17, 2017

Enigma of the Day: Rutgersella

Work this week took me to Delaware Water Gap National Recreation Area on the New Jersey–Pennsylvania border, where the Delaware River has taken advantage of geologic weakness to make a shortcut through the Appalachians, and its tributaries descend hundreds of feet in numerous scenic waterfalls.

Like these

Sunday, September 10, 2017

When ammonites got bored

I'm heading out of the office for a few days, so nothing particularly profound for this entry. It seemed like a good excuse to highlight some variety in the fossil record, so here are some ammonites that decided not to look like ammonites.

Sunday, August 27, 2017

75 years of "Hadrosaurian Dinosaurs of North America"

This Thursday will mark the 75th anniversary of the publication of "Hadrosaurian Dinosaurs of North America", published August 31, 1942. Written by Richard Swann Lull and Nelda E. Wright, "Hadrosaurian Dinosaurs of North America" is one of the classics of dinosaur science, and even today is one of the basic building blocks of any serious work on duckbills. As a GSA Special Paper, it is available for download, so if you have institutional access and pretty much any level of scholarly interest in hadrosaurs, you should pick up a copy.