“Don't be a frog!“ people say in jest when someone hesitates instead of acting straight away. However to be called a frog should actually be a reason to strengthen one's self-confidence. After all frogs are real winners – at least from the point of view of evolutionary biology: Nearly 6.000 species are known today.
Specimen of the South African clawed frog (Xenopus laevis), that zoologists at Jena University are doing research on. Photo: Jan-Peter Kasper/University Jena
“In terms of numbers frogs are superior to all the other amphibians, and even mammals“, says Professor Dr. Lennart Olsson from the Friedrich Schiller University Jena (Germany). Professor Olsson's research group for Systematic Zoology examines these animals’s special secret of success. “We are interested in how the frogs developed in such a great variety and which evolutionary new development is responsible for making frogs so particularly successful“, Jennifer Schmidt from Olsson's team explains.
Their evolutionary success is literally written all over the frogs' faces: Certain forms of cartilage and bone structures in the region of the head of the tadpoles are among the frogs' “innovations“. These structures only to be found in frogs appear in the oral region. They enable the tadpoles – of the South African claw frog (Xenopus laevis) – particularly well to chip vegetarian food from the soil and from stones or to filter it from the water.
In their latest study which has been published in the science magazine “Journal of Anatomy“ together with colleagues from Ulm Jennifer Schmidt analysed the central factor for the development of these morphologically distinctive features of the tadpoles. It is well known from earlier analyses, that the gene “FOXN3“ plays a key role in the embryonal development of the heads of claw frogs. “It is responsible for the normal development of cartilages, bones and muscles“, Jennifer Schmidt explains.
In the newly published study the 25 year old doctoral candidate and scholar of the Konrad-Adenauer-Stiftung analysed larvae of the claw frog after the “FOXN3“-gene had been cut off. Then she compared them with untreated larvae. “Our analyses with microCT show that the larvae without an intact ‘FOXN3’-gene are developing normally up to a certain time.“ But then the development slows down, says Jennifer Schmidt. “On the whole these animals grow more slowly.“ Most of all the cartilages, the bones and muscles don't develop properly. Deformations and loss of functions occur. However not all cartilages and muscles are affected by the cut-off gene. “We were able to show that the ‘FOXN3’ most of all influences the development of the cartilages in the oral region and the gills“, Professor Olsson points out. These structures in particular belong to the evolutionary new developments typical of frogs, which are missing in other amphibians. Jennifer Schmidt would like to continue her analyses in her thesis. “We are going to compare the embryonal development of the claw frogs with those of other amphibians“, the zoologist says. It would be interesting to find out to what extent the genetic control of those new developments changed in the course of the evolution.Original Publication:
Ute Schönfelder | Uni Jena
Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...
UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration
"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...
Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.
Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
16.01.2017 | Power and Electrical Engineering
16.01.2017 | Information Technology
16.01.2017 | Power and Electrical Engineering