"Pesticides make the life of earthworms miserable"
Link: http://www.sciencedaily.com/releases/2014/03/140325113232.htm
Monday, March 31, 2014
"Pesticides make the life of earthworms miserable"
March 2014
Although pesticides are sprayed on crops to help them grow, the effect they have on earthworms living in the soil under the plants is devastating. New research shows that because worms have developed methods to detoxify themselves so that they can live in soil sprayed with fungicide, they only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed, according to a Danish/French research team that studied earthworms that were exposed to pesticides over generations.
The researchers set up an experiment to study the behavior of the earthworm species Aporectodea caliginosa. They moved two portions of farmed soil with worms into the lab. One portion was taken from a local organic field, the other from a local conventionally cultivated field that had been sprayed with fungicide for 20 years. This soil had leftovers of the internationally commonly used fungicide Opus at a level common in fields. When crops are sprayed with fungicide, only a small part of the chemical is absorbed by the plant. The waste can be up to 70 per cent, and much of the fungicide ends up in the soil. Over generations the worms have developed a method to detoxify themselves.
"Salamanders shrinking as their mountain havens heat up"
March 2014
Salamanders in some of North America's best habitat are shrinking fast as their surroundings get warmer and drier. As a result, the salamanders are forced to burn more energy. Specimens caught in the Appalachian Mountains from 1957 to 2007 and wild salamanders caught at the same sites in 2011-2012 have recently been studied. Animals measured after 1980 averaged 8 percent smaller than those caught in 2011-2012 - one of the fastest rates of changing body size ever recorded.
The study was prompted by the work of University of Maryland Prof. Emeritus Richard Highton and headed by Karen R. Lips, an associate professor of biology at the University of Maryland. The study found that between 1957 and 2012, six salamander species got significantly smaller, while only one got slightly larger. On average, each generation was one percent smaller than its parents' generation, the researchers found.The researchers compared changes in body size to the animals' location and their sites' elevation, temperature and rainfall. They found the salamanders shrank the most at southerly sites, where temperatures rose and rainfall decreased over the 55-year study.
Furthermore, to discover how climate change affected the animals, Clemson University biologist Michael W. Sears used a computer program to create an artificial salamander, which allowed him to estimate a typical salamander's daily activity and the number of calories it burned. Using detailed weather records for the study sites, Sears was able to simulate the behavior of individual salamanders. The simulation showed the modern salamanders were just as active as their forbears had been. But to maintain that activity, they had to burn 7 to 8 percent more energy and Sears explained that cold-blooded animals' metabolisms speed up as temperatures rise. In order to get the extra needed energy, salamanders may spend more time foraging for food or resting in cool ponds, and less time hunting for mates. The smaller animals may have fewer young, and may be more easily picked off by predators.
"Salamanders shrinking as their mountain havens heat up"
Link: http://www.sciencedaily.com/releases/2014/03/140325154230.htm
Salamanders in some of North America's best habitat are shrinking fast as their surroundings get warmer and drier. As a result, the salamanders are forced to burn more energy. Specimens caught in the Appalachian Mountains from 1957 to 2007 and wild salamanders caught at the same sites in 2011-2012 have recently been studied. Animals measured after 1980 averaged 8 percent smaller than those caught in 2011-2012 - one of the fastest rates of changing body size ever recorded.
The study was prompted by the work of University of Maryland Prof. Emeritus Richard Highton and headed by Karen R. Lips, an associate professor of biology at the University of Maryland. The study found that between 1957 and 2012, six salamander species got significantly smaller, while only one got slightly larger. On average, each generation was one percent smaller than its parents' generation, the researchers found.The researchers compared changes in body size to the animals' location and their sites' elevation, temperature and rainfall. They found the salamanders shrank the most at southerly sites, where temperatures rose and rainfall decreased over the 55-year study.
Furthermore, to discover how climate change affected the animals, Clemson University biologist Michael W. Sears used a computer program to create an artificial salamander, which allowed him to estimate a typical salamander's daily activity and the number of calories it burned. Using detailed weather records for the study sites, Sears was able to simulate the behavior of individual salamanders. The simulation showed the modern salamanders were just as active as their forbears had been. But to maintain that activity, they had to burn 7 to 8 percent more energy and Sears explained that cold-blooded animals' metabolisms speed up as temperatures rise. In order to get the extra needed energy, salamanders may spend more time foraging for food or resting in cool ponds, and less time hunting for mates. The smaller animals may have fewer young, and may be more easily picked off by predators.
"Whales dive to nearly two miles depth, for over two hours"
March 2014
Dispersed throughout the world's oceans, the Cuvier's beaked whales' frequent dives deep into the ocean make them difficult for researchers to study. However, recently Scientists Gregory Schorr from Cascadia Research Collective and colleagues monitored Cuvier's beaked whales' record-breaking dives to depths of nearly two miles below the ocean surface and some dives lasted for over two hours.
The scientists analyzed the whales' dive data from satellite-linked tags that recorded the diving behavior and locations of eight Cuvier's beaked whales off the Southern California coast. Researchers collected over 3,700 hours of diving data, including depth and time of each dive. The scientists recorded 1100 deep-dives, averaging 0.87 miles deep, and 5600 shallow-dives, averaging about 0.17 miles deep. The deepest dive recorded was one that reached nearly two miles below the ocean surface, and the longest lasted 137 minutes.
This dive not only exceeded the previous Cuvier's beaked whale diving records of about 1 mile deep and 95 minutes, but also the current mammalian dive record previously set by the southern elephant seal at about 1.5 miles deep and 120 minutes. W\What sets the Cuvier beaked whale apart from the deep-diving elephant seals and sperm whales is that the elephant seals and sperm whales require an extended recovery period after long, deep dives, whereas Cuvier's beaked whales average less than two minutes at the surface between dives.
"Whales dive to nearly two miles depth, for over two hours"
Link: http://www.sciencedaily.com/releases/2014/03/140326182037.htm
Dispersed throughout the world's oceans, the Cuvier's beaked whales' frequent dives deep into the ocean make them difficult for researchers to study. However, recently Scientists Gregory Schorr from Cascadia Research Collective and colleagues monitored Cuvier's beaked whales' record-breaking dives to depths of nearly two miles below the ocean surface and some dives lasted for over two hours.
This dive not only exceeded the previous Cuvier's beaked whale diving records of about 1 mile deep and 95 minutes, but also the current mammalian dive record previously set by the southern elephant seal at about 1.5 miles deep and 120 minutes. W\What sets the Cuvier beaked whale apart from the deep-diving elephant seals and sperm whales is that the elephant seals and sperm whales require an extended recovery period after long, deep dives, whereas Cuvier's beaked whales average less than two minutes at the surface between dives.
"Coal plant closure in China led to improvements in children's health"
March 2014
According to a study led by researchers at the Columbia Center for Children's Environmental Health at the Mailman School of Public Health, decreased exposure to air pollution in utero has proven to be linked with improved childhood developmental scores and higher levels of brain-derived neurotrophic factor (BDNF), a key protein for brain development. This study, the first to assess BDNF and cognitive development with respect to prenatal exposure to polycyclic aromatic hydrocarbons (component of air pollution commonly emitted from coal burning), looks at the closure of a coal-burning power plant in China.
Deliang Tang, MD, DrPH, and his colleagues pursued two groups of mother-child pairs from pregnancy into early childhood. One group was made up of mothers pregnant while the coal power plant was still open and the other after it closed. Using the standardized test the Gesell Developmental Schedule (GDS), developmental delay was determined.
The researchers found that decreased PAH exposure resulting from the power plant closure was associated with both increased BDNF levels and increased developmental scores. PAH-DNA adducts were significantly lower in the babies born after the coal power plant shutdown as compared to those born before the closure, indicating a significant exposure reduction. The impacts of PAH exposure and BDNF on developmental scores was also analyzed considering all the children, including both the pre- and post-closure groups. Increased scores in the average, motor, and social areas (seen in the GDS) were linked with higher levels of BDNF. "The results provide important insight into the relationship between PAH exposure, BDNF, and developmental outcomes, and evidence for BDNF as a marker for the neurodevelopment effects of exposure to air pollution."
"Coal plant closure in China led to improvements in children's health"
Link: http://www.sciencedaily.com/releases/2014/03/140326142311.htm
Deliang Tang, MD, DrPH, and his colleagues pursued two groups of mother-child pairs from pregnancy into early childhood. One group was made up of mothers pregnant while the coal power plant was still open and the other after it closed. Using the standardized test the Gesell Developmental Schedule (GDS), developmental delay was determined.
The researchers found that decreased PAH exposure resulting from the power plant closure was associated with both increased BDNF levels and increased developmental scores. PAH-DNA adducts were significantly lower in the babies born after the coal power plant shutdown as compared to those born before the closure, indicating a significant exposure reduction. The impacts of PAH exposure and BDNF on developmental scores was also analyzed considering all the children, including both the pre- and post-closure groups. Increased scores in the average, motor, and social areas (seen in the GDS) were linked with higher levels of BDNF. "The results provide important insight into the relationship between PAH exposure, BDNF, and developmental outcomes, and evidence for BDNF as a marker for the neurodevelopment effects of exposure to air pollution."
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