In territorial species with polygynous mating systems, reproductive success reflects phenotypic variation. At the gross level, such phenotypic variation can include that of body size and weapon morphology, as well as of weapon function and performance. In a study published in the September issue of The American Naturalist, A. Kristopher Lappin (Northern Arizona University) and Jerry F. Husak (Oklahoma State University) use the eastern collared lizard (Crotaphytus collaris ), a sexually dimorphic lizard in which the jaws of males function as a weapon in fights, to test the hypothesis that weapon performance (i.e., bite force) is a better predictor of fitness than body size and weapon size.
The study finds that bite-force performance was a strong predictor of reproductive success. However, no size measure was correlated with any estimate of mating success or with potential reproductive output. These results counter the conventional wisdom that bigger is always better, and they support the hypothesis that weapon performance, which is likely to directly influence fight outcomes, has far stronger effects on fitness than size. The strong influence of weapon performance on reproductive success suggests that selection acts on weapon performance, which in turn drives the evolution of weapon morphology. As such, the use of morphology as a proxy for performance and its presumed extensions to fitness should be based, whenever possible, on empirical morphologyperformance relationships.
The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)
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,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
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