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I have been finding a lot of inclusions in a batch of coprolites from the Smoky Hill Chalk that assumed were bits of cartilage. One of the newer specimens from that batch had a piece of the material in question on the surface; enabling me to view it from the side. They look like little teeth, so now I don't know what I have. I have one other specimen that has a couple of the little tooth-like structures intact (one that I posted a while back that has possible Ptychodus tooth fragments). Is this skin with denticles, cartilage, a skull part or some sort of tooth plate? As always, any help is greatly appreciated.

It's been a good week for fossiling in New Mexico...found this one in a dry wash in west-central NM. The nearest upstream units were (from nearest to far) kmf-Menefee, kpl-Point Lookout Sandstone and the Satan tongue of the Mancos shale (kms). I've always thought of the Western Interior Seaway as fairly shallow and the shark a deep variety, but the lit says the extant cousin patrols 100m to 1,300m and the WIS was as deep as 750, so there's habitat, I would think. Thoughts? Thanks!

Scientists Are Putting Tens of Thousands of Sea Fossils Online The Western Interior Seaway is gone, but not forgotten Erin Blakemore, Smithsonian Magazine, June 22, 2017 http://www.smithsonianmag.com/smart-news/scientists-are-putting-tens-thousands-sea-fossils-online-180963792/ Award Abstract #1645520 Digitization TCN: Collaborative Research: The Cretaceous World: Digitizing Fossils to Reconstruct Evolving Ecosystems in the Western Interior Seaway, National Science Foundation https://www.nsf.gov/awardsearch/showAward?AWD_ID=1645520&HistoricalAwards=false Yours, Paul H.

From rocks in Colorado, evidence of a 'chaotic solar system' University of Wisconsin-Madison, February 22, 2017 http://news.wisc.edu/from-rocks-in-colorado-evidence-of-a-chaotic-solar-system/ https://www.sciencedaily.com/releases/2017/02/170222131512.htm http://www.astrobio.net/also-in-news/rocks-colorado-evidence-chaotic-solar-system/ The paper is: Ma, C., S. R. Meyers, and B. B. Sageman. Theory of chaotic orbital variations confirmed by Cretaceous geological evidence. Nature, 2017; 542 (7642): 468-470 DOI: 10.1038/nature21402 http://www.nature.com/nature/journal/v542/n7642/full/nature21402.html Related paper: Sageman, B. B., J. Rich, M. A. Arthur, G. E. Birchfield, and W. E. Dean, 1997, Evidence for Milankovitch Periodicities in Cenomanian-Turonian Lithologic and Geochemical Cycles, Western Interior U.S.A. Journal of Sedimentary Research, Section B: Stratigraphy and Global Studies Vol. 67 (1997) No. 2. (March), Pages 286-302 http://www.earth.northwestern.edu/research/sageman/PDF/97.Sageman.etal.pdf Yours, Paul H.

While doing a search at Paleobiology Database, I was curious to see if I might find records of marine vertebrates from the Cenomanian-Santonian of the Utah, Montana, Idaho, and Arizona because most tetrapods found in the Cenomanian-Santonian of Nebraska, Kansas, and the Dakotas are primarily mosasaurs, plesiosaurs, pterosaurs, marine turtles, and seagoing birds (e.g. Ichthyornis, Hesperornis) and terrestrial vertebrates have been found in the Western Interior dating from the Cenomanian-Santonian interval (e.g. Oryctodromeus, Eolambia, Sonorasaurus, Albanerpeton cifellii, Nothronychus graffmani, various species of mammals like Ameribataar, and terrestrial lizards). Given the paleogeography of North America during the Cenomanian, would it reasonable to assume that Cenomanian terrestrial tetrapods retreated farther west into areas of Utah, Arizona, Idaho, and Montana that were not covered by the Western Interior Seaway to escape rising sea levels?