It has been the accepted view among evolutionary biologists since Darwin published his Origin of Species in 1859 that measurable evolutionary changes occur slowly, often taking hundreds of generations. This view may now be about to change.
Pygmy grasshoppers exist in many different color variants and in many types of environment. Through a series of experiments and studies in nature, Magnus Karlsson discovered that the distribution between the color variants of pygmy grasshoppers differs across different environments. In recently burnt over areas, a very high proportion of the grasshoppers are black. In unburnt areas, on the other hand, the black variant is unusual. What's more, the proportion of black grasshoppers changes very rapidly between generations in the burnt areas, whereas the proportion in unburnt areas remains the same over the same period of time.
Magnus Karlsson presents data that show that the pygmy grasshoppers' color changes by natural selection. He believes that the primary cause of these changes is birds and other animals that hunt using their vision. The black grasshoppers are simply less visible against the burnt background, so they survive more often. But as the environment changes and becomes more complex, the advantage of being dark diminishes, and other color variants can once again increase in number.
In his experiments, Magnus Karlsson has also shown that the color pattern of the pygmy grasshopper is genetically conditioned and is passed on from parent to offspring. On the other hand, various environmental factors, such as crowdedness or the substrate the grasshoppers grow up on, do not affect their color. In other words, there is no indication that the grasshoppers themselves can change their color depending on what environment they are surrounded by. Therefore, the great differences that exist between burnt and unburnt environments are the result of unusually rapid evolutionary change.
But it is not only that evolution sometimes proceeds rapidly; variation itself also offers major advantages. In groups consisting of many different color variants, survival is higher than in groups with less color variation. This means quite simply that variable groups may find it easier to adapt to environmental changes and that they are more productive.
The practical significance of Magnus Karlsson's discoveries is broad and just as varied as his grasshoppers. He believes this new knowledge can be used in planning preservation projects for threatened species and to improve yields in agriculture.
"But the most important part of the dissertation is that I have shown that evolution sometimes proceeds incredibly rapidly. This is huge," says Magnus Karlsson.
His dissertation is titled Evolution in Changing Environments Revealed by Fire Melanism in Pygmy Grasshoppers.
Contact: Magnus Karlsson, phone: +46 (0)480-446219; mobile: +46 (0)73-5626014 or email@example.com
Pressofficer Karolina Ekstrand; +46-76 647 60 30; firstname.lastname@example.org
Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel
Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Business and Finance
22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy