Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Who am I – and if so, how many?DNA sequences reveal the true identity of Pelodiscus

23.09.2011
A research team from the Senckenberg Research Institute Dresden has identified many different genetic lineages in the softshell turtle genus Pelodiscus, representing different species.

Traditionally it has been assumed that only the species Pelodiscus sinensis belonged to the genus examined. As a foodstuff, Chinese softshell turtles are the most economically important turtles in the world, with an annual trade volume of many hundreds of millions of specimens. The accompanying study is being published today in the "Journal of Zoological Systematics and Evolutionary Research".


Chinese softshell turtle Pelodiscus sinensis
© Markus Auer (Senckenberg)

It is probably safe to say that none of the 300 million turtles that land on a plate in China each year are particularly interested to know the species to which they belong, but for scientists the discovery of different genetic lineages is of enormous significance. Due to its ease of breeding the turtle is often used as a model organism for embryological and physiological studies, so that a correct identification of the species is of paramount importance, not only in the fields of taxonomy and systematics.

Prof. Uwe Fritz, one of the Dresden authors of the study, confirms this: “While until now these turtles have been used as models in many scientific works, nobody actually knew what species they were. This led to considerable contradictions or non-reproducible results, because different species were used in different publications.”

The Chinese softshell turtle (Pelodiscus sinensis) is a strange looking animal: its shell is – as the name already suggests – soft, the long neck is flexible enough to allow the reptile even to see behind himself, and the trunk-like nose proves to be an excellent snorkel in shallow waters. Around the world there are more than 300 different turtle species, only 30 of which have a soft shell. Instead of an ossified shell, the softshell turtles, with a length of up to 30 centimetres, have a leather-like, flexible skin on their back and belly.

Together with his colleague Heiko Stuckas, Fritz examined the DNA of two 180-year-old softshell turtle shells from the Berlin Natural History Museum (Museum für Naturkunde). In 1834 the greatly shrunken and dried-out samples had served the German zoologist Arend Friedrich August Wiegmann as a basis for describing the species Pelodiscus sinensis.

Tiny pieces of tissue were removed from the shells by the Dresden researchers and parts of the genetic makeup of the turtles were defined with the help of the most up-to-date techniques. What is promising here is above all the analysis of the mitochondrial DNA, as these are present to a much greater degree compared to the DNA of the cell nucleus, thus minimising conservation problem.

Unfortunately, the attempt to gain DNA from the first turtle shell failed completely – the remnants of the animal were simply too old and too dried out. However, the second shell proved to be a great success for the research team! The analysis of the DNA sequences led to the conclusion that the genus Pelodiscus contains at least four and not – as previously believed – one species. For the first time, and with the help of the sequences from the Berlin sample, which is more or less the “original standard” for the species Pelodiscus sinensis, it could be clarified which of the four species is actually the “real” Chinese softshell turtle.

This finding is not only of great importance to the field of science; the turtles themselves can also benefit. At present all species that are collated under Pelodiscus sinensis have been placed on the red list of endangered species by the International Union for Conservation of Nature and Natural Resources (IUCN). However, some of the “newly discovered” species could actually be considered to be even more seriously endangered at present and may therefore enjoy greater protection.

In future, due to the results of the research, the different species will no longer be “lumped together” – at least by scientists – but rather can now be named precisely.

Publication: Stuckas, H. & Fritz, U. Identity of Pelodiscus sinensis revealed by DNA sequences of an approximately 180-year-old-type specimen and a taxonomic reappraisal of Pelodiscus species (Testudines: Trionychidae) (2011), J Zool Syst Evol Res doi: 10.1111/j.1439-0469.2011.00632.x

Contact:

Prof. Dr. Uwe Fritz
Senckenberg Naturhistorische Sammlungen Dresden
Abteilungsleiter Museum für Tierkunde
Königsbrücker Landstr. 159
01109 Dresden
Tel. 0351 795841 4326
Fax 0351 795841 4327
E-Mail: Uwe.Fritz@senckenberg.de
Press Office Senckenberg Gesellschaft für Naturforschung
Judith Jördens
Senckenberganlage 25
63065 Frankfurt/Main
Tel. 069-7542 1434
E-Mail: judith.joerdens@senckenberg.de
The research of life forms in their diversity and their ecosystems, climate research and geology, the search for past life and ultimately the understanding of the entire Earth-Life system – that is what the SENCKENBERG Gesellschaft für Naturforschung works for. Exhibitions and museums are the window to natural science, by which means Senckenberg shares current scientific results with the public and provides an insight into past ages and the diversity of nature.

Judith Jördens | idw
Further information:
http://www.senckenberg.de

Further reports about: Chinese herbs DNA DNA sequence Pelodiscus turtle shell

More articles from Life Sciences:

nachricht Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Camera on NASA's Lunar Orbiter survived 2014 meteoroid hit

29.05.2017 | Physics and Astronomy

Strathclyde-led research develops world's highest gain high-power laser amplifier

29.05.2017 | Physics and Astronomy

A 3-D look at the 2015 El Niño

29.05.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>