Water-color by Ahlberg (representing Elginerpeton from Scotland) showing roughly what a Devonian tetrapod might have looked like.
In the 19th century a fossil was uncovered in Belgium that was believed to be the jaw of a fish. Now a team of scientists have shown that it is in fact a fossil from an ancestor of all present-day land animals. It is the first discovery of a so-called tetrapod from the Devonian Period in continental Europe, which may trigger an interest in re-examining objects in museums.
In collaboration with researchers from France, England, and Belgium, Per Ahlberg, professor of evolutionary organism biology at Uppsala University, has demonstrated for the first time that four-legged fish, tetrapods, existed on the European continent during the Devonian Period (about 365 million years ago). These first land vertebrae became the ancestors of all present-day vertebrate amphibians, reptiles, birds, and mammals--and humans. The find also resembles the known “four-legged fish” Ichthyostega that was found by Swedish scientists in Greenland in the 1930s. Fossils of tetrapods from the Devonian Period are extremely rare. In recent years fragments have been found in the US, Scotland, Latvia, and China, among other places, but none of these bear any striking resemblance to Ichthyostega.
The fossil from Belgium is fragmentary (a portion of a lower jaw) but is interesting for several reasons:
Today we have considerably more detailed anatomical knowledge about the earliest tetrapods than 20 or 100 years ago, which makes it possible to identify them even from tiny fragments, such as portions of a lower jaw. In the past it would have been necessary to have at least the better part of a skull (or the rest of the skeleton) in order to recognize a tetrapod. Methods for extracting the fossil from its enclosing stone have also advanced substantially. A new and extremely interesting technique is CT scanning, entailing a series of "x-ray sections" through a fossil, thus visualizing its three-dimensional structure even while it is fully embedded in stone.
Anneli Waara | alfa
Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute
Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine