SCIENCE INITIATIVE HARIPAD KERALA INDIA

Germany’s insects are disappearing ?


           In just 3 decades, insect populations in German nature reserves have plummeted by more than 75%, according to a new study. The reasons for the decline aren’t clear, but the pattern is consistent over a swath of western and northern Germany, from the region around Bonn and Cologne to the countryside south of Berlin. For 27 years, members of the Krefeld Entomological Society near Dusseldorf have monitored flying insect populations—everything from parasitic wasps to hoverflies and wild bees—in dozens of nature reserves. In recent years, they noticed a steep decline in their catch, with biomass dropping by some 82% in the summer when insect populations peak. Their attempts to match the decline with changes in weather, landscapes, and plant coverage—in collaboration with scientists in the Netherlands and the United Kingdom—don’t explain the loss, they report today in PLOS ONE. The scientists speculate that intensive agriculture surrounding the nature reserves has played a role, but they don’t have data on factors such as pesticide use in neighboring fields. The decline is likely having wide-ranging effects on plants and other animals, such as insect-eating birds. The researchers say that better monitoring of these crucial, but overlooked, members of ecosystems is urgently needed. Read more...

What gives frog tongues the gift of grab



Frogs’ remarkable power to tongue-grab prey — some as big as mice or as oddly shaped as tarantulas — stems from a combo of peculiar saliva and a supersquishy tongue.
The first detailed analysis of the stickiness of frog saliva shows that the fluid can shift rather abruptly from gooey to runny, says mechanical engineer Alexis Noel of Georgia Tech in Atlanta. Those quick changes come in handy during the various phases of a single tongue strike. And it all works because the tongue itself is so soft, Noel and colleagues report February 1 in Journal of the Royal Society Interface.
Internet videos of frogs feasting sparked Noel’s curiosity about their ability “to eat furry things, hairy things, slimy things,” she says, and to do so with speed and power. A frog tongue strikes five times more quickly than a human can blink.
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Mineral veins found in Mars's Gale Crater were formed by the evaporation of ancient Martian lakes, a new study has shown.

Drill hole into the John Klein target within Sheepbed Member of Yellowknife Bay, with a light-toned sulfate veinlet visible on the back wall. The light-toned veins have been identified as sulfates by ChemCam (Nachon et al.; Schroeder et al.) and CheMin (Vaniman et al.). Drill hole is 1.6 cm diameter. Image is white balanced. Scale bar is 2 cm.
Credit: Image courtesy of University of Leicester
The research, by Mars Science Laboratory Participating Scientists at The Open University and the University of Leicester, used the Mars Curiosity rover to explore Yellowknife Bay in Gale Crater on Mars, examining the mineralogy of veins that were paths for groundwater in mudstones.The study suggests that the veins formed as the sediments from the ancient lake were buried, heated to about 50 degrees Celsius and corroded.Professor John Bridges from the University of Leicester Department of Physics and Astronomy said: "The taste of this Martian groundwater would be rather unpleasant, with about 20 times the content of sulphate and sodium than bottled mineral water for instance!"However as Dr Schwenzer from The Open University concludes, some microbes on Earth do like sulphur and iron rich fluids, because they can use those two elements to gain energy. Therefore, for the question of habitability at Gale Crater the taste of the water is very exciting news."The researchers suggest that evaporation of ancient lakes in the Yellowknife Bay would have led to the formation of silica and sulphate-rich deposits.Subsequent dissolution by groundwater of these deposits -- which the team predict are present in the Gale Crater sedimentary succession -- led to the formation of pure sulphate veins within the Yellowknife Bay mudstone.The study predicts the original precipitate was likely gypsum, which dehydrated during the lake's burial.
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