Evolutionary biologists have developed a wide range of techniques to reconstruct the evolutionary history of particular groups of plants and animals. These techniques reveal much about the diverse patterns of evolution of life on earth, but few generalities have emerged, leading many scientists, such as the late Stephen Jay Gould, to conclude that each group of living things evolves in its own idiosyncratic manner. But now biologists at Washington University in St. Louis have proposed a general pattern among groups in the timing of evolutionary diversification.
Using novel statistical and analytical techniques, a group headed by Jonathan Losos, Ph.D. and Allan Larson, Ph.D., both Washington University professors of biology in Arts & Sciences, examined two important dimensions in the evolutionary diversification of four groups of lizards: the ages of branching points on the evolutionary trees of the lizard groups and variation among branches in morphological (body) traits, such as limb length and head size.
The researchers found that the four lizard groups differed in both respects. For example, in Australian agamid lizards, a disproportionate number of branching events occur deep (early) in the evolutionary tree, whereas, at the other extreme, among the South American Liolaemus lizards, the branching points are evenly distributed throughout the tree.
Tony Fitzpatrick | EurekAlert!
Microscope measures muscle weakness
16.11.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
Good preparation is half the digestion
16.11.2018 | Max-Planck-Institut für Stoffwechselforschung
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
09.11.2018 | Event News
06.11.2018 | Event News
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16.11.2018 | Health and Medicine
16.11.2018 | Life Sciences
16.11.2018 | Life Sciences