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It seems that lazy clams are less likely to go extinct! NPR news article Link to article (may be behind paywall, I'm not sure) Don

New research suggests evolution might favor 'survival of the laziest' August 21, 2018, University of Kansas http://news.ku.edu/2018/08/15/new-research-suggests-evolution-might-favor-‘survival-laziest’ https://phys.org/news/2018-08-evolution-favor-survival-laziest.html Luke C. Strotz, Erin E. Saupe, Julien Kimmig, and Bruce S. Lieberman, 2018, Metabolic rates, climate and macroevolution: a case study using Neogene molluscs. Proceedings of the Royal Academy B Published 22 August 2018.DOI: 10.1098/rspb.2018.1292 http://rspb.royalsocietypublishing.org/content/285/1885/20181292 Yours, Paul H.

I picked this little shell from the bottom of a tribolite fossil. It appears to have a layer of gold in or on it. It doesn't look like pyrite. But I'm no expert.... Any help would be great. Please excuse the photos...this speciman is very small. I took the pics on top of a penny.

Hi Guys- I spent hundreds of hours with my kids at all of the cool places looking for fossils, arrowheads, rocks, bugs, snakes, and whatever. This is one of those under the bridge finds that I have not been able to ID. This was found under the bridge in south Tarrant County, TX. Any ID info appreciated-

Hello everyone! I recently won a "rolling auction" lot that was put up by @digit. Ken sent me a very heavy box that contained the fossils that I won, as well as some additional specimens. This afternoon, while my son was napping, I tried to identify the molluscs that were collected by Ken at Cookiecutter Creek in Florida. What follows are pictures of the specimens that Ken sent me, as well as my guesses regarding their identity (fyi - I searched the online image gallery of the Florida Museum/University of Florida website in order to come up with my guesses). I appreciate any input/guidance that fellow TFF members can give me - thanks in advance!!! Monica Specimens #1 and #2: Bivalves I think that the specimen on top in each picture is Phacoides pectinatus and the specimen on the bottom is Chione chipolana. Please compare with the following images from the Florida Museum: Phacoides pectinatus: http://www.flmnh.ufl.edu/invertpaleo/display.asp?catalog_number=25110&gallery_type=Florida Mollusca-Bivalvia Chione chipolana: http://www.flmnh.ufl.edu/invertpaleo/display.asp?catalog_number=73007&gallery_type=Florida Mollusca-Bivalvia

Took a family trip to Saltburn yesterday, just up from where we normally go (Redcar) and made some discoveries, one of which looks like a nautiloid. I made a video of that last one, the possible nautiloid:

Hello, Not really a "hunting trip", just a quick look around, because the somewhat "famous" Miocene locality Weitendorf, Styria, Austria is a natural monument and collecting is strictly forbidden. However, not everybody minds this... There is a large, recent dig near the new access ramp. Situation on the photos is as found at 15. April 2017. Lots of broken fossils are lying around. Best regards Franz Bernhard

In another thread I recently presented a bivalve which I had found whose shell is excellently preserved. All the positive comments prompted me to write a little side note on calcitic and aragonitic preservation of shells. In the course of writing this however, I realized how little I actually know about the subject. Here's what I wrote: "Apparently almost all molluscs originally developed aragonitic shells, which, although less stable than calcite, provided better protection from predators since it is harder. Some combine both polymorphs with aragonite inside and calcite outside, since it doesn't dissolve as readily as the latter and apparently magnesium plays a role here as well. My observations in the field have however indicated to me that at least in the Jurassic layers I am familiar with it is often the case that in any given layer, bivalves and brachiopod shells are as a whole much better and more often preserved than those of the ammonites. I do know that at over some stretch in geological history, the aragonite was converted in most cases to the more stable calcite. Perhaps bivalves and brachiopods had thicker shells or a different shell structure to those of the ammonites, which in turn were more susceptible to dissolution before they could be completely converted? It sure would interest me if anyone else could educate me on this subject." Thinking about this again, I'm not sure if one can generalize in comparing these orders, since I also know that some ammonites have thick shells and some bivalves have thin ones. I was just hoping that someone out there knows a bit more about the subject and could enlighten me a bit.

While on vacation in Costa Rica in 2009, I spotted some fossil shells in situ and am hoping someone might know their age or formation. The site is called Playa Limoncito, on the Pacific coast of Puntarenas province a couple of miles south of Tarcoles. The tour guide was aware of the fossiliferous rocks along the beach, but he didn't know how old they were. The exact species are probably unidentifiable from the cross-sections, but I am hoping that someone might know what geological formation is exposed or the approximate age.

I've googled and googled but can't find a definitive family tree for ammoniods/cephalopods &c. I'm looking for relationships between ammonites, nautiloids, belemnites, turrilites etc. Does that make sense? Thanks J