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Although Charles Darwin lived and worked in the 19th century, modern evolutionary biologists are far from exhausting all avenues of inquiry regarding birds and evolution. For example, in the 1990s, researchers such as Russ Greenberg, ornithologist from the Smithsonian Institution in the United States, began to explore a new question concerning the relationship between climate and the evolution of beak size. This question was inspired by Allen’s Rule, which states that warm-blooded animals living in cold climates will have shorter limbs and appendages than those that live in warmer climates. The biological mechanism behind this rule is thermoregulation—more body surface area helps animals to shed heat better whereas less surface area helps them to conserve it. Since a bird’s beak plays a large role in thermoregulation—it has lots of blood vessels and is not covered in feathers—researchers wondered whether hotter climates beget larger beaks and colder climates beget smaller ones. Indeed, studies revealed that climate has influenced beak size, but not which type of climate had more of an overall impact.

It looks like a real heart. And this is the goal of the first entirely soft artificial heart: to mimic its natural model as closely as possible. The silicone heart has been developed by Nicholas Cohrs, a doctoral student in the group led by Wendelin Stark, Professor of Functional Materials Engineering at ETH Zurich. The reasoning why nature should be used as a model is clear. Currently used blood pumps have many disadvantages: their mechanical parts are susceptible to complications while the patient lacks a physiological pulse, which is assumed to have some consequences for the patient.

Former Hurricane Eugene has now weakened to a remnant low pressure area. Infrared imagery from NASA's Aqua satellite revealed that only a small area of convection remains.

Over the next four months, NOAA scientists will launch unmanned ocean vehicles, called Saildrones, from the Arctic to the tropical Pacific Ocean to help better understand how changes in the ocean are affecting weather, climate, fisheries and marine mammals. The wind and solar-powered research vehicles that resemble a sailboat will travel thousands of miles across the ocean, reaching some areas never before surveyed with such specialized technology. 

Chemists at Ruhr-Universität Bochum have tested a new approach for activating chemical reactions based on the element selenium. They demonstrated that selenium can form bonds similar to those of hydrogen bonds, resulting in accelerated reactions. The exact mechanism is described by the team at the Chair of Organic Chemistry 1 in Bochum, including Prof Dr Stefan Huber and Patrick Wonner, in the journal “Angewandte Chemie”, in collaboration with Prof Dr Daniel Werz from Braunschweig University of Technology.

Traditionally, metal complexes are used as activators and catalysts. They form complete, i.e. covalent bonds with the molecule whose reactions they are supposed to accelerate. However, the metals are often expensive or toxic.