Understanding the large-scale processes that shape distributions of species diversity is a long-standing challenge in ecology and can also help set conservation priorities. Regions with highly diverse or unique organisms may be targeted for conservation, but how such a region acquired its species could affect how they should be protected.
Without near-perfect records of where organisms have occurred throughout the past, it can be difficult to determine the processes underlying diversity patterns. In the absence of such detailed information, regions with high diversity or many unique species are often assumed to be hotbeds of species origination, but a new theory demonstrates that such places could instead result from the immigration of species. This theory, outlined in an article to appear in the June 2005 issue of The American Naturalist, also shows how combining the ages of species, determined from the fossil record, with information on where those species currently live can give insight into the past processes that have shaped diversity. Application of the theory to clams, mussels, and other marine bivalves shows that the polar oceans have had higher rates of immigration and extinction and much lower rates of origination than have the tropical and temperate oceans.
This example underscores the importance of considering not just species origination but also extinction and dispersal when testing hypotheses about the geographic distributions of organisms.
Carrie Olivia Adams | EurekAlert!
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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.
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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.
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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.
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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.
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