Researchers from the Université de Montpellier II (France), the Institute of Geology of China, and the ESRF have been able to identify enigmatic fossils from Devonian (about 400 million years) as fructification of charophyte algae. Charophytes are land plants living in fresh water that still exist nowadays. This breakthrough allows researchers to better understand the evolution of these very old plants of the Paleozoic era and to have an improved overview of the climate at this period. The use of powerful X-rays beams to perform high resolution microtomography at the ESRF was one of the major keys in helping to understand the internal structure of these fossils. The results of this research are published in the latest issue of the American Journal of Botany with the title “New insights into Paleozoic charophyte morphology and phylogeny”.
These fossils belong to the enigmatic group of Sycidiales. Since their discovery, in 1934, no one really knew what they actually were. They had been defined as bracken “seeds”, corals or even small crustacean eggs. Thanks to high resolution X-ray synchrotron microtomography on beamline ID19 at the ESRF, the team of scientists succeeded in investigating the three-dimensional structure of these fossils. The samples they used ranged from 500 micron to 4 mm and originated from all around the world. Synchrotron radiation was fundamental for this study since it revealed microscopic details of the internal anatomy of these fossils without damaging them. At present, no other techniques allowing the study of these structures in a non-destructive way are available.
Charophytes fructifications exhibit a complex evolution. They all have quite a rounded shape, but the oldest ones display vertical structures on their outside surface, while the most recent ones present spiral ones. Fossils studied during this research are from the Paleozoic (or Primary era) and show these vertical structures. What surprised the researchers was the presence of an utricule, which was known before only in some Mesozoic (secondary era) charophytes. An utricule is a supplementary protective layer believed to protect the zygote (reproductive cell) against desiccation. The fact that such a structure was acquired during the evolution of these very old algae means that they probably lived in a harsh environment. This structure could be interpreted as an adaptation to strong seasonality with dry summers leading to ephemeral aquatic environments.
Montserrat Capellas | alfa
How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)
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....
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....
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...
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...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy