Monday, 25 May 2015

TW:eed Project meeting - new advances



Recently we held out seventh team meeting of the TW:eed Project, this time at the Department of Zoology, University of Cambridge. 20 members of the project met together for two days of talks, discussions and workshops. As we are now nearing the end of the project (just over a year remaining) it’s really great to see the results coming together and new research avenues being discussed.

Members of Team TW:eed at our seventh project meeting

Advances in the following topics were discussed during the meeting:

  • -       Gypsum and evaporite deposits in the Norham Core
    -       Charcoal and atmospheric oxygen levels
    -       Palynomorphs and biostratigraphy
    -       Regional litho/biostratigraphic correlations and the age of tetrapod-bearing units
    -       New shrimp and arthropod fossil discoveries
    -       New tetrapod, fish and shark fossil discoveries
    -       CT scanning results of delicate tetrapod and fish specimens
    -       Cladistics (evolutionary tree) of tetrapod fossils
    -       Plans for our museum exhibition

We discussed our plans for future fieldwork, with upcoming trips to Virginia, USA and Northumberland/Scottish Borders. In September, several members of the team will be presenting at the upcoming IGCP 596 meeting in Brussels about many aspects of this project.

While in Cambridge I spent a very enjoyable morning examining the shape, texture and structure of fossil vertebrate bones, comparing identified larger bones to the microfossil bone fragments I have been working on. This was very rewarding as at the same time the vertebrate experts (Rob, Jenny and Kelly) examined some of the microfossil specimens I brought with me that my volunteer Hattie has been picking and they were able to identify the majority of them including some rare finds! Next week sees the start of the new Master’s project here at the University of Leicester on the TW:eed Project, with Levi Curry working on a joint sedimentology-micropalaeontology project, so more news to come on that soon!

Until next time
Carys

Wednesday, 6 May 2015

Romer’s Gap tetrapods of Nova Scotia



Last week the first paper from the TW:eed Project was published, on the tetrapods of Horton Bluff, Nova Scotia. The Nova Scotia fossils are the same age as specimens from the Scottish Borders, from the period known as Romer’d Gap. The paper is the first to show that Romer’s Gap may not be a not a true gap in the tetrapod fossil record, but it may be instead caused by biases in fossil collection. 

For decades, isolated fossil bones have been collected from a locality called Blue Beach at Horton Bluff, Nova Scotia. These new specimens have enabled researchers to identify that a diverse tetrapod fauna was present. The paper describes three distinct forms of humerus, two of scapulo-coracoid (part of the shoulder girdle), four of femur, two of tibia and two of pelvis. Although isolated, the shapes of some of these bones are fairly distinctive, allowing the authors to estimate taxonomic diversity at the locality. They conclude that there are at least five different types of tetrapod represented, and can infer the presence of several more, based on the extensive sets of trackways which have been collected over the years. 
 
Tetrapod femur (leg) bones illustrated in the publication


The Blue Beach fauna includes some tetrapods clearly similar to some of the Late Devonian forms, as well as animals more similar to those that appear later in the Carboniferous. This means that some tetrapods survived the end Devonian mass extinction event. This study is the first to illuminate what tetrapod communities looked like in the early Carboniferous and is a great first result for the TW:eed Project.

The lead author on the paper is Jason Anderson from the University of Calgary, along with Tim Smithson and Jenny Clack, and Canadian colleagues Chris Mansky and Taran Meyer. The article is called ‘A Diverse Tetrapod Fauna at the Base of 'Romer'sGap'’ and is published in the journal PLOS ONE, which is online and open access, clicking the link with the article title to view it. You can read more about the results of the study on the TW:eed website, and see a video of the field site. 

Until next time
Carys