Earth

Distressed damsels cry for help

Researchers at the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University have found that fish release a chemical 'distress call' when caught by predators, dramatically boosting their chances of survival.

Fish harbour a chemical substance in their skin that's released upon injury. It triggers fearful and escape behaviour in nearby fish, but until now scientists hadn't identified the benefits to the sender.

Distressed damsels cry for help

In a world first study researchers from Uppsala University, Sweden and James Cook University in Australia and have found that prey fish captured by predators release chemical cues that acts as a 'distress call', dramatically boosting their chances for survival. The findings are published in Proceedings of the Royal Society B.

Fish harbour a chemical substance in their skin that's released upon injury. It triggers fearful and escape behaviour in nearby fish, but until now scientists hadn't identified the benefits to the sender.

Mammoths might have survived except for bad 'mineral diet'

At the end of the Pleistocene mammoths of Northern Eurasia used to experience chronic mineral hunger. As a result they became extinct due to geochemical stress arising on a background of deep abiotic changes in ecosystems. Most likely they were receiving not enough of essential chemical elements. This hypothesis was developed by TSU paleontologists and based on a large-scale, 15-years long research. Detailed information you can find in an article of Sergei Leshchinsky, Head of Laboratory of Mesozoic and Cenozoic continental ecosystems, TSU Faculty of Geology and Geography.

Dartmouth-led study explores wave-particle interaction in atmosphere

HANOVER, N.H. - A Dartmouth-led study sheds light on the impact of plasma waves on high-energy electrons streaking into Earth's magnetic field from space.

The findings are important because relativistic electrons can lead to ozone depletion and threaten orbital satellites, spacecraft and astronauts, and understanding the evolution of Earth's radiation belts could help lessen the effects of these particles.

Seismological Research Letters: Nepal earthquake was less intense than feared

The April 2015 Gorkha earthquake that struck Nepal produced less damage and weaker shaking than might be expected from a magnitude 7.8 quake in the area, according to a group of ten new articles published this week in Seismological Research Letters.

Attosecond physics: Film in 4-D with ultrashort electron pulses

Physicists of the Ludwig-Maximilians-Universität (LMU) in Munich shorten electron pulses down to 30 femtoseconds duration. This enables them to gain detailed insight into atomic motions in molecules.

A team from Ludwig-Maximilians-Universität (LMU) and Max Planck Institute of Quantum Optics (MPQ) has now managed to shorten electron pulses down to 28 femtoseconds in duration. One femtosecond is a millionth of a billionth of a second. Such shutter speeds enable us to directly observe the truly fundamental motions of atoms and molecules in solids, similar to stroboscopy.

Physics of booming and burping sand dunes revealed

Washington, D.C., Oct. 27, 2015 -- Avalanching sand from dune faces in Death Valley National Park and the Mojave Desert can trigger loud, rumbling "booming" or short bursts of "burping" sounds -- behaving as a perfectly tuned musical instrument.

This sound is persistent and the dunes "sing" in frequencies ranging from 70 to 105 Hertz, with higher harmonics. Prior to the onset of a nearly monotone booming, burps of sound of smaller amplitude occur over a significantly broader span of frequencies.

Wall-less Hall thruster may power future deep space missions

Washington, D.C., Oct.27, 2015 - Hall thrusters are advanced electric rocket engines primarily used for station-keeping and attitude control of geosynchronous communication satellites and space probes. Recently, the launch of two satellites based on an all-electric bus has marked the debut of a new era - one in which Hall thrusters could be used not just to adjust orbits, but to power the voyage as well.

QMUL Ph.D. student stumbles upon a new way for producing oldest chemical compounds

A chemistry PhD student from Queen Mary University of London (QMUL) has found a simple way for the first time of producing two chemical compounds that were first discovered in late 19th century, entirely by accident. The discovery could have implications for fighting disease and growing crops, where the sulfur containing compounds called sultones and sultines, play a significant role.

May the 5th force be with you

Discovering possible new forces in nature is no mean task. The discovery of gravity linked to Newton's arguably apocryphal apple experiment has remained anchored in popular culture. In January 1986, Ephraim Fischbach, Physics Professor from Purdue University in West Lafayette, Indiana, had his own chance to leave his mark on collective memory. His work made the front page of the New York Times after he and his co-authors published a study uncovering the tantalising possibility of the existence of a fifth force in the universe.

Rewilding the future

New research shows that the loss of large animals has had strong effects on ecosystem functions, and that reintroducing large animal faunas may restore biodiverse ecosystems.

Rewilding is gaining a lot of interest as an alternative conservation and land management approach in recent years, but remains controversial. It is increasingly clear that Earth harbored rich faunas of large animals - such as elephants, wild horses and big cats - pretty much everywhere, but that these have starkly declined with the spread of humans across the world - a decline that continues in many areas.

Study: Alaskan soil thaw sends carbon directly back into atmosphere

TALLAHASSEE, Fla. -- Samples of permafrost soil from deep below the ground in an Alaskan tunnel are providing new clues in the quest to understand what exactly happens as northern regions of the world warm and begin to thaw.

Extinction of Pleistocene herbivores induced major vegetation and landscape changes

The extinction of large herbivores such as mammoths could explain massive prehistoric changes in vegetation and landscape structure. But it has wider implications, explaining more frequent fires in modern-day ecosystems for instance. Modern and paleo-ecologists joined forces in an international study led by the Netherlands Institute of Ecology (NIOO-KNAW). The results are being published online by PNAS this week.

Elephants boost tree losses in South Africa's largest savanna reserve

Washington, DC-- Protected areas, such as nature reserves and national parks, play a crucial role in sheltering wildlife, such as African elephants, from hunting and habitat destruction. But it's important that conservation managers understand how the vegetation in these natural protected zones is affected by the population growth that is spurred by this animal safeguarding.

Loss of large land mammals could change landscapes forever

Large land animals such as elephants, wildebeest and other big plant-eaters are worth preserving in part because their disappearance could have permanent effects on the plants and animals they coexist with, according to an analysis of past large-mammal extinctions in North and South America.