New Butterfly Species Identified
Two amateur entomologists, one a Commerce Department cartographer, have identified a new species of pale blue butterfly they call the "Holly Azure," common along the Atlantic Coast.
Cartographer Harry Pavulaan, of Herndon, and co-researcher David Wright, a physician from Philadelphia, published their findings in August in the Taxonomic Report, summarizing 20 years of research into the butterfly they call Celastrina idella.
Pavulaan said the Holly Azure looks very much like a close cousin, the Spring Azure, but Spring Azure larvae feed on blueberry plants and appear about three weeks before the Holly Azure, whose larvae feed on holly.
Also, Pavulaan added, the Holly Azure is common from Savannah, Ga., north to southern New Jersey. The Spring Azure is common in New York and New Jersey. The two species overlap only in the south Jersey forest known as the Pine Barrens.
Pavulaan said the pair's research suggests that the two azures were once the same species, "but the populations were separated and evolved in different ways. When they came into contact they couldn't interbreed anymore," or reproduce in the other's host.
Babies' Vision Improves Rapidly
When babies are born, their eyesight is still developing. A newborn's vision improves rapidly in the first years of life as the brain establishes the network of connections needed to translate light into images. Now, new research has provided clues to how this works.
Daphne Maurer of the Hospital for Sick Children in Toronto and colleagues studied 28 infants ages 1 week to 9 months who were born with cataracts. Right after the cataracts were surgically removed, the babies' vision was as poor as newborns.
But their vision improved rapidly after the cataracts were removed, with some improvement showing up as soon as one hour after being exposed to visual input, the researchers report in the Oct. 1 issue of Science.
Predicting Divorce in 3 Minutes
Psychologists say they have figured out a way to identify couples who are likely to get divorced just by watching how they discuss something they disagree about for three minutes.
Couples who begin these discussions with a lot of negative emotions, words and gestures are much more likely to end up splitting up, according to John Gottman of the University of Washington and colleagues.
The researchers videotaped 124 couples who had been married for less than nine months as they talked about issues that had been the source of conflict, such as money. They then followed the couples to see whose marriages didn't last.
Those that began negatively were much more likely to get divorced, the researchers report. For example, wives who started a discussion by saying something like "You're lazy and never do anything around the house" instead of "You didn't take out the trash last night," were more likely to get divorced.
"It was possible to predict marital outcome over a six-year period using just the first three minutes of data for both husbands and wives," the researchers write in the fall issue of the journal Family Process. "This suggests that for both husbands and wives, the start-up of the conflict discussion is critical in predicting divorce or marital stability."
A Love Potion for Frogs
Scientists for the first time have identified a substance that a male amphibian uses to attract a mate.
Paul A. Wabnitz of the University of Adelaide in Australia and colleagues identified a pheromone produced by male tree frogs.
"To our knowledge, this pheromone, which we have named splendipherin, is the first pheromone from an anuran [frog or toad] to be identified," the researchers write in the Sept. 30 issue of Nature. Pheromones previously have been found in other types of animals.
The researchers identified the substance by analyzing chemicals contained in glands in male tree frogs' heads over a three-year period. Levels of splendipherin peaked during the frogs' January-to-March breeding season. Tests in a glass case showed that female tree frogs were attracted to the substance but that it had no effect on other types of frogs.
"We conclude that the aquatic, male sex pheromone splendipherin is therefore species specific," they write.
Polarized Light Guides Spiders
If you've ever wondered how spiders find their way around, researchers in Sweden have found a clue, at least for one species. The Drassodes cupreus spider, an inch-long creature found in many parts of northern Europe, appears to have a built-in compass.
Marie Dacke of the University of Lund and colleagues found that the spiders have a pair of specialized secondary eyes that do not form images. Instead, these eyes use a built-in filter to determine precisely the direction in which the light falling on them is polarized.
This compass appears to work best at dusk and dawn. The spiders are most active after sunset, when they rely on their interpretations of polarized light to guide them back to the nest after foraging, the researchers write.