The time is here once again. Time to gather around and take a well deserved hiatus from all the politics of the day. Science talk is here. New discoveries, new takes on old knowledge, and other bits of news are all available for the perusing in today's information world. Over the fold are selections from the past week from a few of the many excellent science news sites around the world. Today's tidbits include stretched polymer snaps back smaller than its start, evidence of feasting in early humans, climate change implicated in the decline of horseshoe crabs, famed Tasmanian devil euthanised after tumor (facial cancer) found, and self-assembling photovoltaic technology that repairs itself. Pull up that beach chair and relax. There is plenty of room for everyone. Settle in for one more session of Dr. Possum's science education and entertainment.
Featured Stories
Children around the world love stretchy materials such as crazy bands. Now scientists have discovered a polymer that returns to a size smaller than the original after being stretched.
Imagine a sheet of Saran Wrap that could fix a microscopic puncture before the hole ever got big enough to see. This would require that the polymer molecules immediately around the tear could somehow jump into action and perform new chemistry to build bridges across the hole.
At least that is the promise of this new discovery. We shall see.
The sharing of food in communal gatherings such as feasts is a human characteristic of human social behavior.
At a burial cave in the Galilee region of northern Israel, (researcher) Munro and her colleague Leore Grosman of Hebrew University in Jerusalem uncovered the remains of at least 71 tortoises and three wild cattle in two specifically crafted hollows, an unusually high density for the period. The tortoise shells and cattle bones exhibited evidence of being cooked and torn apart, indicating that the animals had been butchered for human consumption.
Each of the two hollows, says Munro, was manufactured for the purpose of a ritual human burial and related feasting activities. The tortoise shells were situated under, around and on top of the remains of a ritually-buried shaman, which suggests that the feast occurred concurrently with the ritual burial. On their own, the meat from the discarded tortoise shells could probably have fed about 35 people, says Munro, but it's possible that many more than that attended this feast.
Declining horseshoe crab populations may be the result of more than one factor but climate change is suspected of being a large contributor.
While the current decline in horseshoe crabs is attributed in great part to overharvest for fishing bait and for the pharmaceutical industry, the new research indicates that climate change also appears to have historically played a role in altering the numbers of successfully reproducing horseshoe crabs. More importantly, said (researcher) King, predicted future climate change, with its accompanying sea-level rise and water temperature fluctuations, may well limit horseshoe crab distribution and interbreeding, resulting in distributional changes and localized and regional population declines, such as happened after the last Ice Age.
The famed Tasmanian devil, Cedric, was once thought to be immune to the facial cancer virus devastating the species.
The Tasmanian devil population has plummeted by 70 percent since Devil Facial Tumor Disease was first discovered in 1996. The snarling, fox-sized creatures - made famous by their Looney Tunes cartoon namesake Taz - don't exist in the wild outside Tasmania, an island state south of the Australian mainland. (snip)But in late 2008, Cedric developed two small facial tumors after being injected with a different strain of the cancer, which causes grotesque facial growths that eventually grow so large, it becomes impossible for the devils to eat. Current estimates suggest the species could be extinct within 25 years due to the prolific spread of the cancer.
Plants use sunlight to produce energy through photosynthesis and repeat the cycle through many years. Now scientists have learned to mimic part of the process to allow self-repairing photovoltaic systems.
One of the problems with harvesting sunlight is that the sun's rays can be highly destructive to many materials. Sunlight leads to a gradual degradation of many systems developed to harness it. But plants have adopted an interesting strategy to address this issue: They constantly break down their light-capturing molecules and reassemble them from scratch, so the basic structures that capture the sun's energy are, in effect, always brand new.
By use of applied chemistry researchers are able to replicate part of this process.
The individual reactions of these new molecular structures in converting sunlight are about 40 percent efficient, or about double the efficiency of today's best commercial solar cells. Theoretically, the efficiency of the structures could be close to 100 percent, he says. But in the initial work, the concentration of the structures in the solution was low, so the overall efficiency of the device — the amount of electricity produced for a given surface area — was very low. They are working now to find ways to greatly increase the concentration.
Other Worthy Stories of the Week
New predatory dinosaur discovered in Romania
Dramatic climate change is unpredictable
Oilsands mining and processing are polluting the Athabasca River
Nature's quality control in yeast
Acidifying oceans spell marine biological breakdown by "end of century"
Shallow water habitats important for young salmon and trout
Marine animals suggest evidence for a trans-Antarctic seaway
Mosquitos use several different kinds of odor sensors to track human prey
Extensive relict coral reef found in South Pacific
Tracing the big picture of Mars atmosphere
Physicists propose quantum refrigerator
Astranaut's eye view: Time-lapse videos of Earth
Most new tropic farmland from slashing forests
Brainy worms: Evolution of the cerebral cortex
Ant bodyguards protect trees in the savannah from elephants
For even more science news:
General Science Collectors:
Alpha-Galileo
BBC News Science and Environment
Eureka Science News
LiveScience
New Scientist
PhysOrg.com
SciDev.net
Science/AAAS
Science Alert
Science Centric
Science Daily
Scientific American
Space Daily
Blogs:
A Few Things Ill Considered Techie and Science News
Cantauri Dreams space exploration
Coctail Party Physics Physics with a twist.
Deep Sea News marine biology
Laelaps more vertebrate paleontology
List of Geoscience Blogs
ScienceBlogs
Space Review
Techonology Review
Tetrapod Zoologyvertebrate paleontology
Science Insider
Scientific Blogging.
Wired News
Science RSS Feed: Medworm
The Skeptics Guide to the Universe--a combination of hard science and debunking crap
Daily Kos regular series:
Daily Kos University, a regular series by plf515
This Week in Science by DarkSyde
This Week in Space by nellaselim
Overnight News Digest:Science Saturday by Neon Vincent. OND tech Thursday by rfall.
Weekend Science by AKMask
All diaries with the DK GreenRoots Tag.
All diaries with the eKos Tag
NASA picture of the day. For more see the NASA image gallery or the Astronomy Picture of the Day Archive.
Hourglass Nebula, NASA, Public Domain