Magic Monday and science talk comes once again. Today is the time to gather around and take a well deserved hiatus from all the politics of the day. 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 for platinum catalysts smaller may be better, the effect of competition in disturbed ecosystems, 2-billion-year-old fossils may be earliest multicellular life, nitrogen pollution alters global change from the ground up, saber tooth tigers also had strong forelimbs, oil spills may raise arsenic levels in the ocean, and melting ice allows a new realm for archeology. Pull up that beach chair and settle in for one more session of Dr. Possum's science education and entertainment.
Featured Stories
The industry standard for catalysts these days is the costly (about $2000 an ounce) element platinum
...under high-pressure conditions, single crystals of platinum are not as stable as nanoclusters, which actually become more stabilized as carbon monoxide molecules are co-adsorbed together with platinum atoms.
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In the future, the use of these stable platinum nanoclusters as fuel cell catalysts may help to boost performance and reduce costs.
Current wisdom suggests the effects of competition are lessened in survival after ecosystem disturbance by wildfire, hurricanes, floods, and other events as all species try to survive. New research may lead to reevaluation of this premise.
...the species extinctions that occurred through different levels of disturbance could be partly attributed to competition between species. And the rate of extinctions attributable to competition was greater at higher levels of disturbance.
The findings contradict the intermediate disturbance hypothesis, which suggests that at high levels of disturbance, the species that survive will be those that are hardy under disturbed conditions. At low disturbance, the hypothesis suggests that the ecosystem will be dominated by species that are good competitors. At some intermediate disturbance level, the good competitors will have an opportunity to gain a foothold without being destroyed by disturbance, but will not be able to out-compete the hardier species or exclude less-fit species.
The origins of multicellular life on earth are being unraveled bit by bit. Fossil discoveries are helping solve the mystery.
The newly described fossils, which have yet to be given a species name, make Grypania less solitary. They lived at roughly the same time — Grypania in what is now the northern United States, the new fossils in Gabon. By raising the possiblity that multicellularity was a trend rather than an aberration, they also hint at an answer to the question of why complex life evolved, not just when.
Just a few million years before Grypania and the newly discovered fossils appear in the fossil record, Earth experienced what’s called the Great Oxidation Event. The sudden evolution of photosynthesizing bacteria radically changed Earth’s atmosphere, kick-starting its transformation from nearly oxygen-free into today’s breathable air.
Scientists have for years hoped to see a response by plants to increasing CO2 concentrations that would include greater plant growth. Nitrogen was postulated to be a stimulating factor for this greater growth.
Plants build their tissue primarily with the CO2 they take up from the atmosphere. The more they get, the faster they tend to grow—a phenomenon known as the "CO2 fertilization effect." However, plants that photosynthesize greater amounts of CO2 will also need higher doses of other key building blocks, especially nitrogen. The general consensus has been that if plants get more nitrogen, there will be a larger CO2 fertilization effect. Not necessarily so, says a new paper.
Different species respond in different ways. The entire population must be taken into consideration.
Fearsome as the bit of a saber tooth tiger must have been, being pinned by powerful forelimbs in advance added to the terror.
Sabertooth arm bones were not only larger in diameter than other cats, they also had thicker cortical bone, the dense outer layer that makes bones strong and stiff. Thicker cortical bone is consistent with the idea that sabertooth forelimbs were under greater stress than would be expected for cats their size, (researcher) Meachen-Samuels explained. Just like weight-bearing exercise remodels our bones and improves bone density over time, the repeated strain of grappling with prey may have resulted in thicker and stronger arm bones in saber-toothed cats.
As if we did not have enough bad news about oil spills, now comes news that oil spilled into the ocean may raise arsenic levels in the water.
Arsenic is a poisonous chemical element found in minerals and it is present in oil. High levels of arsenic in seawater can enable the toxin to enter the food chain. It can disrupt the photosynthesis process in marine plants and increase the chances of genetic alterations that can cause birth defects and behavioural changes in aquatic life. It can also kill animals such as birds that feed on sea creatures affected by arsenic.
Climate change is upon us as anyone can see in the melting ice packs around the world. Archeologists have discovered a new source of artifacts in these melting ice flows. One of these new generation researchers
found the atlatl dart (a 10,000-year-old wooden hunting weapon), a spear-like hunting weapon, melting out of an ice patch high in the Rocky Mountains close to Yellowstone National Park.
Now the race is on to find these organic artifacts before deterioration sets in.
Other Worthy Stories of the Week
Super closeups of crazy bug eyes Photos, photos.
Ants use their own Velcro to catch super sized prey
Gene leads to longer shelf life for tomatoes and possibly other fruits
Stirring the ocean: Calculating the role of swimmers
Science historian cracks the "Plato" code
Ostriches provide clues to dinosaur movement
More fish than thought may live in the ocean's depths(PDF)
New technique improves efficiency of biofuel production
Cosmic rays are made of protons
"Butterfly effect" in the brain makes the brain intrinsically unreliable
Origin of the Milky Way's ancient stars
Ultrafine particles in air pollution may heighten allergic inflammation in asthma
Honing in on a black hole's jets
Scientists find moon whiskers
Arctic climate may be more sensitive to warming than thought
Man-made global warming began with ancient hunters
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. This week OND by palantir.
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.
Seagull Nebula, NASA, Public Domain