About This Blog

Science Happenings with Rightler is a blog designed to share information about the cool stuff that is going on in the world of science. New discoveries, cosmic fluff, and all in between are grist for the mill. I will be giving my own take on the events as they happen.

Tuesday, April 29, 2014

Newfound Purple-Pink Mineral Is Like No Other


PutnisiteA new purple-pink mineral that has a chemical composition and crystalline structure unlike any of the known 4,000 minerals has been discovered at a mining site in Western Australia, researchers report.

Now called putnisite, the mineral was discovered in a surface outcrop of Polar Bear Peninsula, Southern Lake Cowan, north of Norseman. While workers with a mining company were prospecting for nickel and gold, one of them noticed the bright-pink grains and sent the mineral to the Commonwealth Scientific and Industrial Research Organization (CSIRO), and then it was sent to Peter Elliott, a research associate with the South Australian Museum, for examination.
And, sure enough, the crystal was novel.
"A mineral is different from currently known minerals if it has either a different chemical composition or it has a different crystal structure, or sometimes both," Elliott told Live Science in an email. "Occasionally, a new mineral will have a chemistry that is very different to other minerals, or it will have a crystal structure that is very different to other minerals." 
Elliott added, "Putnisite, a strontium calcium chromium sulfate carbonate, has both a unique chemical composition and a unique crystal structure." (The color of putnisite crystals ranges from pale to dark purple, with a pink streak, according to the researchers.)
Found on volcanic rock, the new mineral occurs as tiny crystals just 0.02 inches (0.5 millimeters) in diameter, and looks like spots of dark pink on dark-green-and-white rock; under a microscope, the mineral appears as cubelike crystals.
"When the rocks in the Lake Cowan area were deposited millions of years ago, they contained small concentrations of strontium calcium chromium and sulfur," Elliott said. "Over time, weathering released these elements and concentrated them, allowing putnisite to crystallize."
Though it is not uncommon to find a new mineral — 50 to 100 such specimens have been discovered in each of the past several years — they aren't usually discovered by miners, Elliott said.
"Often, they are found in museum mineral collections," he said. "Many new minerals are found by mineral collectors who will forward a specimen they have found to a mineralogist at a museum of [a] university for identification."
The researchers are not sure if the mineral, described in Mineralogy Magazine, has any practical uses. Putnisite gets its name from Australian mineralogists Andrew and Christine Putnis.

Friday, April 25, 2014

Dolphins Put Sponges on Snouts to Snag Elusive Snacks


Dolphins can use sponges as tools to snag food they could not otherwise grab, researchers say.
This is the first direct evidence that dolphins can use toolsto carve out unique places in the food chain, scientists added.
Dolphins are often ranked among the smartest members of the animal kingdom. They engage in complex forms of communication, may recognize themselves in mirrors, can understand sign language, and can learn to poke an underwater keyboard to request toys to play with.
Recently, scientists discovered Indo-Pacific bottlenose dolphins in Shark Bay off the coast of Australia apparently use tools in the wild. Specifically, the most common foraging tactic dolphins practice in deep-water channels involves carrying sponges on their snouts — more than 60 percent of all female dolphins practice sponging, and up to half of all males born to "spongers" in one part of the bay grow up to become spongers themselves. 
The sponges may help protect dolphin beaks from sharp rocks, stingray barbs and other painful experiences as they probe the seafloor for food. However, it was unknown whether tool use helped spongers get food they could not obtain otherwise, as is the case with humans and nut-cracking chimpanzees.
To solve this mystery, evolutionary biologists Michael Krützen and Sina Kreicker at the University of Zurich and their colleagues analyzed chemicals in tissue samples from both 11 spongers and 27 non-spongers. The investigators focused on molecules known as fatty acids, which come from prey and thus shed light on the diets of the dolphins.
The scientists discovered spongers apparently have completely different diets from non-spongers.
"We were blown away as to how strong the differences between tool users and non-tool users were, especially given that these animals live in the same habitat," Krützen told Live Science.
These findings are the first direct evidence that dolphin tool use can help them acquire new spots in the food chains of their ecosystems. "This has been demonstrated in only a few species so far, and has been implicated as a significant driver for human evolution," Krützen said.
The researchers suggest that spongers may feed on fish that live near the seafloor, ones lacking organs known as swim bladders that help fish stay buoyant in the water. These bottom-dwelling fish are difficult to spot using the echolocation, or biological sonar, that dolphins normally use to pinpoint prey — the complex surface of the seafloor can muddy a dolphin's echolocation.
It remains uncertain what fish sponges actually help spongers catch. To identify this prey, researchers would have to sample the fatty acids of all potential food in the bay, including ones living near, on or buried in the seafloor. "This was beyond the scope of the project, but might be done in the future," Krützen said.
In future studies, the scientists would also like to discover what benefits accrue from another tool-use strategy, known as shelling, that dolphins in Shark Bay practice; with shelling, dolphins carry seashells around in their mouths.