The NASA Mars rover Curiosity this week is driving within a shallow depression called "Yellowknife Bay," providing information to help researchers choose a rock to drill.

The NASA Mars rover Curiosity used its left Navigation Camera to record this view of the step down into a shallow depression called "Yellowknife Bay." (Credit: NASA/JPL-Caltech)

Yellowknife Bay is within a different type of terrain from what the rover has traversed since landing inside Mars' Gale Crater on Aug. 5, PDT (Aug. 6, UTC). The terrain Curiosity has entered is one of three types that intersect at a location dubbed "Glenelg," chosen as an interim destination about two weeks after the landing.Using Curiosity's percussive drill to collect a sample from the interior of a rock, a feat never before attempted on Mars, is the mission's priority for early 2013. After the powdered-rock sample is sieved and portioned by a sample-processing mechanism on the rover's arm, it will be analyzed by instruments inside Curiosity.

Curiosity reached the lip of a 2-foot (half-meter) descent into Yellowknife Bay with a 46-foot (14-meter) drive on Dec. 11. The next day, a drive of about 86 feet (26.1 meters) brought the rover well inside the basin. The team has been employing the Mast Camera (Mastcam) and the laser-wielding Chemistry and Camera (ChemCam) for remote-sensing studies of rocks along the way.

On Dec. 14, Curiosity drove about 108 feet (32.8 meters) to reach rock targets of interest called "Costello" and "Flaherty." Researchers used the Alpha Particle X-Ray Spectrometer (APXS) and Mars Hand Lens Imager (MAHLI) at the end of the rover's arm to examine the targets. After finishing those studies, the rover drove again on Dec. 17, traveling about 18 feet (5.6 meters) farther into Yellowknife Bay. That brings the mission's total driving distance to 0.42 mile (677 meters) since Curiosity's landing.

One additional drive is planned this week before the rover team gets a holiday break. Curiosity will continue studying the Martian environment from its holiday location at the end point of that drive within Yellowknife Bay. The mission's plans for most of 2013 center on driving toward the primary science destination, a 3-mile-high (5-kilometer) layered mound called Mount Sharp.

NASA's Mars Science Laboratory Project is using Curiosity during a two-year prime mission to assess whether areas inside Gale Crater ever offered a habitable environment for microbes. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the project for NASA's Science Mission Directorate in Washington.

More information about Curiosity is online athttp://www.jpl.nasa.gov/msl , http://www.nasa.gov/msl andhttp://mars.jpl.nasa.gov/msl/ . You can follow the mission on Facebook at: http://www.facebook.com/marscuriosity and on Twitter at: http://www.twitter.com/marscuriosity .

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University of Toronto Faculty of Medicine researchers have uncovered a genetic basis for fundamental differences between humans and other vertebrates that could also help explain why humans are susceptible to diseases not found in other species.

The team sequenced and compared the composition of hundreds of thousands of genetic messages in equivalent organs, such as brain, heart and liver, from 10 different vertebrate species, ranging from human to frog. They found that alternative splicing -- a process by which a single gene can give rise to multiple proteins -- has dramatically changed the structure and complexity of genetic messages during vertebrate evolution.Scientists have wondered why vertebrate species, which look and behave very differently from one another, nevertheless share very similar repertoires of genes. For example, despite obvious physical differences, humans and chimpanzees share a nearly identical set of genes.

The results suggest that differences in the ways genetic messages are spliced have played a major role in the evolution of fundamental characteristics of species. However, the same process that makes species look different from one another could also account for differences in their disease susceptibility.

"The same genetic mechanisms responsible for a species' identity could help scientists understand why humans are prone to certain diseases such as Alzheimer's and particular types of cancer that are not found in other species," says Nuno Barbosa-Morais, the study's lead author and a computational biologist in U of T Faculty of Medicine's Donnelly Centre for Cellular and Biomolecular Research. "Our research may lead to the design of improved approaches to study and treat human diseases."

One of the team's major findings is that the alternative splicing process is more complex in humans and other primates compared to species such as mouse, chicken and frog.

"Our observations provide new insight into the genetic basis of complexity of organs such as the human brain," says Benjamin Blencowe, Professor in U of T's Banting and Best Department of Research and the Department of Molecular Genetics, and the study's senior author.

"The fact that alternative splicing is very different even between closely related vertebrate species could ultimately help explain how we are unique."

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A meteorite that exploded as a fireball over California's Sierra foothills this past spring was among the fastest, rarest meteorites known to have hit Earth, and it traveled a highly eccentric orbital route to get here.

The researchers found that the meteorite that fell over Northern California on April 22 was the rarest type known to have hit Earth -- a carbonaceous chondrite. It is composed of cosmic dust and presolar materials that helped form the planets of the solar system.An international team of scientists presents these and other findings in a study published Dec. 21, in the journal Science. The 70-member team included nine researchers from UC Davis, along with scientists from the SETI Institute, NASA and other institutions.

The scientists learned that the meteorite formed about 4.5 billion years ago. It was knocked off its parent body, which may have been an asteroid or a Jupiter-family comet, roughly 50,000 years ago. That began its journey to Sutter's Mill, the gold discovery site that sparked the California Gold Rush.

As it flew toward Earth, it traveled an eccentric course through the solar system, flying from an orbit close to Jupiter toward the sun, passing by Mercury and Venus, and then flying out to hit Earth.

The high-speed, minivan-sized meteorite entered the atmosphere at about 64,000 miles per hour. The study said it was the fastest, "most energetic" reported meteorite that's fallen since 2008, when an asteroid fell over Sudan.

"If this were a much bigger object, it could have been a disaster," said co-author and UC Davis geology professor Qing-zhu Yin. "This is a happy story in this case. "

Before entering Earth's atmosphere, the meteorite is estimated to have weighed roughly 100,000 pounds. Most of that mass burned away when the meteorite exploded. Scientists and private collectors have recovered about 2 pounds remaining.

UC Davis is 60 miles west of the El Dorado county towns of Coloma and Lotus, where pieces of the meteorite were found on residents' driveways and in local forests and parks.

When the meteorite fell, Yin, whose lab contains some of the country's most specialized equipment to measure the age and composition of meteorites, searched for and collected pieces of the fallen meteorite with students and volunteers. He also led a 35-member subgroup of international researchers to study and share information about the meteorite's mineralogy, internal textures, chemical and isotopic compositions and magnetic properties.

Meteorites like Sutter's Mill are thought to have delivered oceans of water to Earth early in its history. Using neutron-computed tomography, UC Davis researchers helped identify where hydrogen, and therefore water-rich fragments, resides in the meteorite without breaking it open.

For the first time, the Doppler weather radar network helped track the falling carbonaceous chondrite meteorite pieces, aiding scientists in the quick recovery of them, the study reports. Yin expects that the weather radar data in the public domain could greatly enhance and benefit future meteorite recoveries on land.

"For me, the fun of this scientific gold rush is really just beginning," said Yin. "This first report based on the initial findings provides a platform to propel us into more detailed research. Scientists are still finding new and exciting things in Murchison, a similar type of meteorite to Sutter's Mill, which fell in Victoria, Australia, in 1969, the same year Apollo astronauts Neil Armstrong and Buzz Aldrin returned the first lunar samples to the Earth. We will learn a lot more with Sutter's Mill."

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The above story is reprinted from materials provided byUniversity of California - Davis.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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1. P. Jenniskens, M. D. Fries, Q.-Z. Yin, M. Zolensky, A. N. Krot, S. A. Sandford, D. Sears, R. Beauford, D. S. Ebel, J. M. Friedrich, K. Nagashima, J. Wimpenny, A. Yamakawa, K. Nishiizumi, Y. Hamajima, M. W. Caffee, K. C. Welten, M. Laubenstein, A. M. Davis, S. B. Simon, P. R. Heck, E. D. Young, I. E. Kohl, M. H. Thiemens, M. H. Nunn, T. Mikouchi, K. Hagiya, K. Ohsumi, T. A. Cahill, J. A. Lawton, D. Barnes, A. Steele, P. Rochette, K. L. Verosub, J. Gattacceca, G. Cooper, D. P. Glavin, A. S. Burton, J. P. Dworkin, J. E. Elsila, S. Pizzarello, R. Ogliore, P. Schmitt-Kopplin, M. Harir, N. Hertkorn, A. Verchovsky, M. Grady, K. Nagao, R. Okazaki, H. Takechi, T. Hiroi, K. Smith, E. A. Silber, P. G. Brown, J. Albers, D. Klotz, M. Hankey, R. Matson, J. A. Fries, R. J. Walker, I. Puchtel, C.-T. A. Lee, M. E. Erdman, G. R. Eppich, S. Roeske, Z. Gabelica, M. Lerche, M. Nuevo, B. Girten, S. P. Worden. Radar-Enabled Recovery of the Sutter's Mill Meteorite, a Carbonaceous Chondrite Regolith Breccia. Science, 2012; 338 (6114): 1583 DOI: 10.1126/science.1227163

 A global network of people monitoring bee populations may form an early warning system alerting scientists to dangers threatening the world's food system and economies.

A researcher checks a pan trap to identify bee species. (Credit: Derek Masaki)

In an article published online Dec. 12 in the journal Conservation Biology, LeBuhn and her co-authors outlined a simple and cost-effective method for enacting a monitoring system. The study found that counting and identifying bees regularly for five years at about 200 locations would produce data accurate enough to detect two to five percent annual declines in bee populations. The program is estimated to cost $2 million and include international sampling sites, although it could be scaled to fit different regional monitoring needs."My goal is to give agencies all around the world an effective way to monitor bees," said San Francisco State University Professor of Biology Gretchen LeBuhn, lead author of a United Nations-sponsored study. "Biologists have talked a lot about how bee populations are declining, but I don't think we actually have good data that acts as an early warning signal for possible problems with our food system."

"The estimated cost of sustaining an international monitoring program is a relatively small investment compared to the potential economic cost of severe pollinator losses," the study said. Thirty-five percent of the global food supply depends on bees and other pollinators, including crops worth nearly $200 billion each year, according to LeBuhn.

"A monitoring program should be simple, repeatable, inexpensive, and, most importantly, have the ability to quickly detect declines if they are occurring," the study said.

The proposed system relies on paid workers around the globe to count and identify bees using simple "pan traps," in which bees are attracted to a brightly-colored pan filled with liquid. To determine scalable sampling techniques, costs and time scales for completing the work, the researchers designed simulations using data from eleven previously published multi-year studies.

The research was funded by the Food and Agriculture Organization of the United Nations, and the monitoring program has already been used in Brazil, Ghana, India, Kenya, Nepal, Pakistan and South Africa, with support from the Global Environment Facility and United Nations Environment Programme. LeBuhn said the long-term goal for the project is to establish a network of monitoring stations to provide data for a global analysis.

"We hope to eventually centralize some of the data collection so that people who are counting bees regionally can contribute to a larger data set."

LeBuhn is also known for organizing the annual "Great Sunflower Project," in which 100,000 citizen scientists across North America volunteer to count bee populations in their own backyards. The project, now in its fifth year, recently found low numbers of bees in urban areas across America, adding weight to the theory that habitat loss is one of the primary reasons for sharp population declines.

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Baylor University researchers are one step closer to understanding the algae that causes a substantial number of fish deaths in more than 18 states.

The study was published in the December issue of Harmful Algae.Golden algae, Texas Tide orPrymnesium parvum, as it is known by its scientific name, produces toxins that can severely impact aquatic organisms. Over the past decade, golden algae blooms have been responsible for the death of tens of millions of fish in Texas reservoirs.

Bryan W. Brooks, Ph.D., professor of environmental science and biomedical studies at Baylor and director of the environmental science graduate program and the environmental health science program, and his research team found that neutral pH levels prevented the algae's bloom development and the toxicity of the algae was greatly diminished.

"Our novel findings identify that surface water pH is a very important factor influencing whether harmful algal blooms of Prymnesium parvum will even occur in a lake or reservoir," Brooks said. "In addition to better understanding the ecology and toxicology of this invasive species, this new information promises to support more sustainable environmental management of fisheries and drinking water supplies."

Brooks and his research team conducted two experiments -- one during pre-bloom period and another during bloom development -- over 21 days to gauge the effect of pH 7 and 7.5 on toxicity of golden algae. The study -- in Lake Granbury, Texas, a common site of destructive golden algae blooms -- also included untreated lake water with pH of 8.5.

"In the bloom development experiment, acute toxicity to fish was observed in the untreated lake water (pH 8.5) and in the pH 7.5 treatment level as early as Day 7. However, the pH 7 treatment levels remained free from acute toxicity throughout the 21-day study," said Krista N. Prosser, Baylor environmental science graduate student and lead author of the study.

Researchers can now better identify when and where harmful blooms may occur and develop solutions to minimize the impact of golden algae.

"Because golden algae blooms appears to originate in coves that experience lower inflows than the main reservoir stems, coves may represent more reasonable management units to create refuge habitats and potentially preempt bloom formation," Brooks said.

Golden algae can be found in the following states: Ala., Ariz., Ark., Calif., Fla., Hawaii, La., Maine, Miss., N.C., N.M., Okla., Pa., S.C., Texas, Wash., W.Va. and Wyo.

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Dec. 23, 2012 — Peatlands (bogs, turf moors) are among the most important ecosystems worldwide for the storage of atmospheric carbon and thus for containing the climate warming process. In the last 30 to 50 years the peat (Sphagnum) mosses, whose decay produces the peat (turf), have come under pressure by vascular plants, mostly small shrubs.

The findings in a nutshell

A new study by scientists from the Swiss Federal Institute for Forest, Snow and Landscape Research WSL and from the Ecole Polytechnique Fédérale de Lausanne (Switzerland) describes for the first time what lies behind this change in vegetation and explains why vascular plants are at an advantage over peat (Sphagnum ) mosses in a warmer climate.

The research team closely monitored four peatland sites at altitudes ranging from 600 m to 1900 m over a period of three years. The selected altitudinal gradient reflects the expected changes in climate conditions for the year 2050[1] in northern Switzerland. They observed that the increase of shrub cover and soil temperature along the altitudinal gradient were responsible for a decrease of almost 50% of the production of new litter by peat mosses, the main contributors to peat accumulation.

The analysis showed that vascular plants can increase the availability of soil nitrogen (a primary nutrient for plant growth) by means of specific compounds contained in their leaves. They exploit the nutrient for their growth through the mediation of specific fungal symbiosis at root level (the mycorrhiza), a process that becomes more and more frequent when soil temperature increases. At the same time, with higher soil temperature vascular plants release a greater amount of organic matter into the soil through their roots (the so called "root exudates") and this stimulates the decomposition activity of soil microbes.

As fewer peat mosses grow, there will be less new peat to store atmospheric carbon. In addition, the increased decomposition activity of soil microbes accelerates the decomposition of old peat. Thus, carbon that might otherwise be kept in storage for millennia can be released into the atmosphere. This situation casts a black shadow on the capacity of peatlands to continue to accumulate atmospheric carbon. As a consequence, peatlands can turn from carbon sinks to carbon sources, thus intensifying the climate warming instead of contributing to reducing it.

Peatlands play a central role in climate protection

Although peatlands are estimated to cover only 3% of the world land surface, they store about 30% of all soil organic matter, an amount equivalent to about 50% of the atmospheric CO2. On global scale, peatlands stock an amount of carbon which is twice the carbon stock of all forest biomass. In this sense, peatlands can be considered as "hot spots" of carbon accumulation and they have contributed, over millennia, to cool the climate by retrieving greenhouse gases from the atmosphere.

In Switzerland, peatlands have become known to the general public because of the Rothenturm initiative, which was followed by an article in the Swiss Constitution in 1987 to save peatlands from destruction.

In peatlands, the accumulation of peat is primarily promoted by a peculiar group of plants called "peat mosses" (technically, Sphagnum mosses), whose litter has antibiotic properties that hamper the decomposing activity of soil microbes. In addition, the presence of abundant water in peatland soil not only promotes the growth of peat mosses (which do not have roots, like vascular plants), but also creates anoxic conditions that further reduce the decomposition of plant litter. In a typical peatland, peat mosses dominate the landscape.

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The above story is reprinted from materials provided bySwiss Federal Institute for Forest, Snow and Landscape Research WSL.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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1. Luca Bragazza, Julien Parisod, Alexandre Buttler, Richard D. Bardgett. Biogeochemical plant–soil microbe feedback in response to climate warming in peatlands. Nature Climate Change, 2012; DOI:10.1038/nclimate1781

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