Spectacular soft tissue fossil. Cells, cell organells and original bio molecules have been found in preserved soft tissue in this 180 million years old fish lizard. This is a photo of the 85 centimeters long fossil, which makes up half thelength of the full animal.
Photo: Johan Lindgren, Lund University.
The Stenopterygius was around two meters long and lived in the Early Jurassic period in an ocean that was situated where southern Germany now is, over a hundred million years before the times of the better known dinosaurs Tyrannusaurus and Triceratops. Now researchers, in a multidisciplinary international collaboration led by a group at the Lund University in Sweden, have investigated a very well preserved fossil which has led to astonishing new knowledge about the dolphin-like creature which they now publish in Nature. The fossil’s integumental parts such as blubber, skin and liver have been studied at both cellular and molecular levels. This has led to a clearer image of what the animal looked like and was structured. One discovery the researchers made was that although 180 million years have passed, there is still some flexibility in parts of the tissue. To be able to perform this in depth analysis the groupe involved Chalmers infrastructure of Chemical imaging.
– We have been looking at melanophores, i.e pigment-containing cells, and skin from the fossil. We have been able to confirm that the cells, after millions of years, still contain important organic elements from lipids and proteins, says Per Malmberg
, director at Chalmers and University of Gothenburgs open infrastructure Chemical imaging
The discovery contributes with renewed knowledge regarding convergent evolution, i.e similar characteristics in different species that have developed due to similar living conditions rather than due to heritage. The fish lizard has several similarities with today’s dolphins and porpoises, but also the leatherback sea turtle, even though they are not related.
The research has been carried out together by universities all over the world, but has been led by researchers at the Lund University. They choose to engage Chalmers because their open infrastructure offer access to NanoSIMS-analysis and analytical competence.
– Me and my colleague Aurélien Thomen from University of Gothenburg, who also is involved in this work, are proud to be able to contribute with an important piece of the puzzle to understand how Stenopterygius functioned. Our infrastructure offers a unique possibility to get high resolution chemical surface analysis and our contribution to the study shows that our infrastructure is world class, says Per Malmberg.
NanoSIMS, as part of Chemical imaging, is a technology that makes it possible to create chemical maps of surfaces. Ranging from hard materials such as fossil to soft matter such as cells, all can be analysed by the
NanoSIMS. It is a quite sensitive technology that may analyse substances at a ppm-level and create images of distribution with a resolution down to 50 nanometres. Chemical imaging is an infrastructure co-owned together with the University of Gothenburg and facilitates the only NanoSIMS instrument in the Nordic countries.
Text: Mats Tiborn