In experiments with butterflies, evolutionary biologists from Leiden University have demonstrated that natural selection is not always the only factor which determines the appearance of an organism. Constraints also appear to play a role at times in determining the progress and outcome of the evolutionary process.
This research from Leiden provides evidence for the hypothesis of Stephen Jay Gould and Richard Lewontin. In 1979, these two scientists stated that Darwin`s theory of natural selection is often incorrectly seen as the sole factor which determines the outcome of evolution. Constraints also play an important role.
For example, constraints play a role in not allowing the development of eyes in the back of the head. Although decidedly advantageous, the evolution of eyes at this location will occur in few animals. This is due to limitations during the development and growth or because no variation for this trait is present in the genetic material. Another form of constraints occurs if two traits are linked to each other. A person with long arms always has long legs.
Michel Philippens | alfa
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Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
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The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
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Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
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