Nanogirl Dr Michelle Dickinson: Can your pet predict an earthquake?

The idea that animals can predict earthquakes has been around for centuries, with records dating back to 373 BC claiming that animals including snakes, rats and weasels abandoned the city of Helice in Greece days before a devastating...

At the Bottom of the Ocean, a Surprising, Gloomy Discovery

Almost two miles below the surface of the Pacific Ocean, on a lonely outcrop of bare rock 100 miles from Costa Rica, researchers on a geological expedition found something odd. As their remotely controlled submersible sunk through the black waters toward the seafloor, they saw a collection of purple lumps dotting the rocky bottom. As they got closer, they resolved themselves into something resembling a bowling ball with suckers. It was a group of female octopuses, of the genus Muusoctopus

Mountain erosion may add CO2 to the atmosphere

Scientists have long known that steep mountain ranges can draw carbon dioxide (CO2) out of the atmosphere -- as erosion exposes new rock, it also starts a chemical reaction between minerals on hill slopes and CO2 in the air, 'weathering' the rock and using CO2 to produce carbonate minerals like calcite.

Polarized object detection in crabs: a two-channel system [RESEARCH ARTICLE]

Melanie Ailin Basnak, Veronica Perez-Schuster, Gabriela Hermitte, and Martin Beron de Astrada

Many animal species take advantage of polarization vision for vital tasks such as orientation, communication, and contrast enhancement. Previous studies have suggested that decapod crustaceans use a two-channel polarization system for contrast enhancement. Here, we characterize the polarization contrast sensitivity in a grapsid crab. We estimated the polarization contrast sensitivity of the animals by quantifying both their escape response and changes in heart rate when presented with polarized motion stimuli. The motion stimulus consisted of an expanding disk with an 82° polarization difference between the object and the background. More than 90% of animals responded by freezing or trying to avoid the polarized stimulus. In addition, we co-rotated the e-vectors of the object and background by increments of 30° and found that the animals’ escape response varied periodically with a 90° period. Maximum escape responses were obtained for object and background e-vectors near the vertical and horizontal orientations. Changes in cardiac response showed parallel results but also a minimum response when e-vectors of object and background were shifted by 45° with respect to the maxima. These results are consistent with an orthogonal receptor arrangement for the detection of polarized light, in which two channels are aligned with the vertical and horizontal orientations. It has been hypothesized that animals with object-based polarization vision rely on a two-channel detection system analogous to that of color processing in dichromats. Our results, obtained by systematically varying the e-vectors of object and background, provide strong empirical support for this theoretical model of polarized object detection.

Powering advances in wireless connectivity for the future

PAWR logo

The National Science Foundation (NSF) announces an important milestone in its Platforms for Advanced Wireless Research (PAWR) effort. In collaboration with an industry consortium of 28 networking companies and associations, NSF is supporting the development and deployment of the first two PAWR research platforms, based in Salt Lake City and New York City. These ...

More at https://www.nsf.gov/news/news_summ.jsp?cntn_id=245045&WT.mc_id=USNSF_51&WT.mc_ev=click


This is an NSF News item.

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