Feeling a Little Reckless … It Could Be a Parasite.
Rodents who are infected with the parasite Toxoplasma gondii seem to lose their fear of cats, or more specifically, the odor of cats. And since those mice are more likely to be eaten, T. gondii benefits because it reproduces in the guts of cats. It turns out that people infected with the parasite also show personality changes. The CDC estimates that more than 20% of people over age 12 are infected with T. gondii, and the vast majority don’t know it. The chemical trick that T.gondii plays on its hosts involves manipulating the concentration of dopamine and hormones in the brain. In people, T.gondii infections seem to correlate with increased risk taking, higher car accident rates,lower conscientiousness and and even schizophrenia.
More at Scientific American.
BBQs v. Diesel 18-Wheelers.
Ever wonder about the plumes of smoke emitted by your barbeque? Scientists at the University of California Riverside did and they conducted an experiment to measure the pollution effects of a typical hamburger barbeque. They estimate that barbecuing a single hamburger produces as many polluting particles as an 18-wheeler diesel truck travelling 143 miles on the freeway. How to limit these particulates will be, to say the least, controversial.
More at Red Orbit.
Building Cleaner Caves to Save the Bats.
The fungal disease known as white nose syndrome has ripped through the hibernating bat population of the East Coast for several years. Because bats eat so many insects, they are a critical link in the ecosystem. The disease so far has no cure, but that doesn’t mean there is no point in trying. In Tennessee, where its many caves provide homes to millions of bats, Cory Holliday and the Nature Conservancy built an 80-foot long artificial cave. The theory is that since the artificial cave can be cleaned after each hibernation period, it may be possible to interrupt the 3-year infection cycle that causes mass bat deaths. The scientists will use recorded bat calls to lure the bats to this new cave.
More at New York Times.
More Worries as Bird Malaria Moves North.
Birds in the tropical regions carry malaria, but it is now found to be spreading north. Along with a warmer Arctic climate, birds that normally carry malaria are expected to spread it to birds, such as snowy owls, that have never before been confronted with the disease. So far, bird malaria has not been seen north of Fairbanks, Alaska, but with rising Arctic temperatures, it appears to be a matter of time before it reaches the most northerly bird populations.
More at Scientific American.
Antbirds and the Moveable Tropical Feast.
Antbirds comprise several species of tropical birds that have turned the art of a free lunch into a lifestyle. As described by Natalie Angiers of the New York Times, these birds follow columns of army ants and pick off the various animals that desperately try to escape their path. Grasshoppers, beetles and other delicacies jump out of the way of the ant army’s destructive march and the antbirds are there to snatch them up. As is often the case, there are other freeloaders: butterflies follow the antbirds to feed on their droppings. Antbirds are becoming so habituated to this feeding habit that they now qualify as official parasites.
The Incredible Artistry of the Male Pufferfish.
Animals can amaze us, but in this instance the lengths to which one male pufferfish went to attract a mate are simply astounding. Michael Harper of Red Orbit describes the discovery of an elaborate “crop circle” on the ocean floor made by a tiny pufferfish using only his tail fin.
There are many examples of monogamous animals, but scientists were surprised at the record of the coyotes living in the urban areas of Chicago. Scientists at Ohio State University not only tracked the coyotes they studied, but actually conducted DNA tests matching pups with their presumed fathers. The result is that Chicago coyotes seem to stand apart with respect to monogamy. As one researcher put it: “In contrast to studies of other presumably monogamous species that were later found to be cheating, such as arctic foxes and mountain bluebirds, we found incredible loyalty to partners in the study population.”
More at Red Orbit.
It’s a Dirty Job But Some Squid Has to Do It.
The vampire squid, reminiscent of Dracula because of its long cloak-like tendrils, has nothing to do with sucking blood. Instead, it serves a much less exotic but clearly more important job. The vampire squid is a virtual garbage disposal for the ocean floor, sucking up everything left behind by other creatures and digesting it. Diving deep beneath the surface and needing only a small fraction of the oxygen that most sea creatures do, the vampire squid mixes it haul of ocean detritus with mucus that it secretes from its suckers.
More at Live Science.
Mosquitoes Adapt, With Dire Consequences.
It is estimated that mosquito-proof bed nets have saved countless lives in Africa by preventing mosquito bites that transmit deadly malaria. Mosquitoes are usually active only at night and thus the bed nets have proved a valuable resource for people most at risk for malaria. However, nature adapts and so do mosquitoes. Scientists have discovered a new species of mosquito which has a new DNA type. It also has a new habit: it is active closer to morning hours than its traditional counterpart. So as the odds of survival shift away from the traditional type of mosquito, these late risers are sure to benefit and efforts to stem Africa’s malaria problem could take a step or two backward.
More at New Scientist.
Bees Can Solve Travelling Salesman Problem.
The travelling salesman problem is a standard in mathematics courses because it appears so simple yet requires prodigious amounts of computation. Finding the most efficient route between several cities is, basically, much more difficult than it seems. However, bees seem to have a natural sense for solving this kind of dilemma. Scientists from the University of Sydney, Rothamsted Research in Harpenden, England and Queen Mary University of London set up a five flower pentagon with about 50 meters between flowers. Sans map and without reading a single mathematics textbook, the bees almost immediately eliminated the vast majority of inefficient routes between the flowers.
More at Science News.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
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