Quantcast

Studies dispute ultraviolet effect on declining amphibian populations

For several years it has been widely believed that increased ultraviolet-B radiation because of thinning of atmospheric ozone was a major culprit in deforming amphibian offspring and dwindling populations. Now two new studies cast serious doubt on that assumption, and the lead author of one says the belief could have had negative impacts on efforts to save amphibians. “All of the concentration on UV might have misdirected our conservation and research priorities,” said Wendy Palen, a University of Washington zoology doctoral student.

‘Heartbeats’ may keep galaxies churning

Until now, astronomers haven’t been able to offer a full explanation for why the Milky Way and other galaxies produce new stars at a relative snail’s pace. While they have known for decades that high turbulence keeps huge clouds of hydrogen gas from condensing into stars, they haven’t identified all the causes of the galactic perturbations. In a coming report researchers in San Diego say they have discovered that a well-known, but overlooked source of heating?regular outbursts of ultraviolet radiation from clusters of very large, bright stars?may play a significant role in keeping the Milky Way’s gas continually stirred up.