Showing posts with label host. Show all posts
Showing posts with label host. Show all posts

Saturday, September 10, 2022

BC'S FOSSIL BOUNTY ON TELUS OPTIK TV

We live in a diverse province edged by mountains, ocean, forests and streams. While our lens is often on the rugged beauty all around us, beneath our feet is yet another world.

Layers of rock hold fossils, each an interface to our deep past. 

Within each fragment, these ancient beings whisper their secrets, share their life experiences, tell us tales of community, how they made a living, who they rubbed shoulders with (or fins, or seedlings...) and convey the essence of a world long embedded in stone.

Join me as we explore the rich fossil bounty of fossil plants, dinosaurs to mighty marine reptiles and the people who unearth them. Discover British Columbia's violent past — how plate tectonics, volcanoes and glaciers shaped the land and why we find plant fossils along the Kitsilano foreshore and marine fossils beneath False Creek. Learn about the science of geochemistry from a palaeontologist who uses fossil teeth to reconstruct ancient environments.

Meet those who call Vancouver home and use this beautiful base for their mining explorations — opening up BC and communities through partnerships that honour First Nations wisdom, show a commitment to social responsibility & sound environmental practices.

​Hear from palaeontologists, geologists, geochemists, science organizations, dinosaur docents, palaeoartists and fossil preparators whose work brings our ancient world to life.

Funding is supported by TELUS STORYHIVE & DINO LAB INC. BC'S FOSSIL BOUNTY — SEASON ONE airs on TELUS Optik TV and the TELUS YouTube Channel to millions of viewers beginning Autumn 2022. Plans for SEASON TWO are in the works. 

Visit www.fossilhuntress.com to learn more and to hear updates on the project.

Friday, July 29, 2022

AN AMMONITE HOSTING WEE BIVALVES

What you are seeing here is a protuberance extruding from the venter of Quenstedtoceras cf. leachi (Sowerby). It is a pathology in the shell from hosting immature bivalves that shared the seas with these Middle Jurassic, Upper Callovian, Lamberti zone fauna from the Volga River basin. The collecting site is the now inactive Dubki commercial clay quarry and brickyard near Saratov, Russia. 

The site has produced thousands of ammonite specimens. A good 1,100 of those ended up at the Black Hills Institute of Geological Research in Hill City, South Dakota. 

Roughly 1,000 of those are Quenstedtoceras (Lamberticeras) lamberti and the other 100 are a mix of other species found in the same zone. These included Eboraciceras, Peltoceras, Kosmoceras, Grossouvria, Proriceras, Cadoceras and Rursiceras. 

What is especially interesting is the volume of specimens — 167 Quenstedtoceras (Lamberticeras) lamberti and 89 other species in the Black Hills collection — with healed predation injuries. It seems Quenstedtoceras (Lamberticeras) lamberti are the most common specimens found here and so not surprisingly the most common species found injured. Of the 1,000, 655 of the Quenstedtoceras (Lamberticeras) lamberti displayed some sort of deformation or growth on the shell or had grown in a tilted manner. 

Again, some of the Q. lamberti had small depressions in the centre likely due to a healed bite and hosting infestations of the immature bivalve Placunopsis and some Ostrea. 

The bivalves thrived on their accommodating hosts and the ammonites carried on, growing their shells right up and over their bivalve guests. This relationship led to some weird and deformities of their shells. They grow in, around, up and over nearly every surface of the shell and seem to have lived out their lives there. It must have gotten a bit unworkable for the ammonites, their shells becoming warped and unevenly weighted. Over time, both the flourishing bivalves and the ammonite shells growing up and over them produced some of the most interesting pathology specimens I have ever seen.    

In the photo here from Emil Black, you can see some of the distorted shapes of Quenstedtoceras sp. Look closely and you see a trochospiral or flattened appearance on one side while they are rounded on the other. 

All of these beauties hail from the Dubki Quarry near Saratov, Russia. The ammonites were collected in marl or clay used in brick making. The clay particles suggest a calm, deep marine environment. One of the lovely features of the preservation here is the amount of pyrite filling and replacement. It looks like these ammonites were buried in an oxygen-deficient environment. 

The ammonites were likely living higher in the water column, well above the oxygen-poor bottom. An isotopic study would be interesting to prove this hypothesis. There's certainly enough of these ammonites that have been recovered to make that possible. It's estimated that over a thousand specimens have been recovered from the site but that number is likely much higher. But these are not complete specimens. We mostly find the phragmocones and partial body chambers. Given the numbers, this may be a site documenting a mass spawning death over several years or generations.

If you fancy a read on all things cephie, consider picking up a copy of Cephalopods Present and Past: New Insights and Fresh Perspectives edited by Neil Landman and Richard Davis. Figure 16.2 is from page 348 of that publication and shows the hosting predation quite well. 

Photos: Courtesy of the deeply awesome Emil Black. These are in his personal collection that I hope to see in person one day. 

It was his sharing of the top photo and the strange anomaly that had me explore more about the fossils from Dubki and the weird and wonderful hosting relationship between ammonites and bivalves. Thank you, my friend!