Army ants, beard microbes and ant-mimicking jumping spiders

Army ant week: Biologist and photographer Alex Wild reported on army ants all last week  in a series of posts on his blog Myrmecos. In one post, he described how army ants link with one another using hooks on their feet: “When the time comes to encamp, they can string together living curtains of ants in a matter of minutes. Army ant bivouacs are made from the ants themselves, a vibrant structure that protects the vulnerable brood and maintains temperature within a single degree of optimal.” Read more or view photos at “Army Ants as Living Legos.” Funky pheromones: Chemical signals, as ecologist and blogger Tracey Switek put it in a recent post on The Olive Tree, “don’t have to just be scents that waft through the air…They can be toxins, which send a very clear signal either because they make the plant taste bad or outright kill or injure anything that tries to eat. We’re all familiar with the culinary herbs such as basil, mint, thyme, cilantro and sage… But the real purpose of those pungent chemicals is to discourage insect predation.” Chemical signals can change the behavior of a species in many ways—for example, pheromones on squid eggs can cause males to become aggressive at the slightest touch (see above video). Read more at “Everybody Stinks: Chemical Signaling in the Undergrowth” and at “Rage-inducing chemical on squid eggs turns males into violent thugs” by Not Exactly Rocket Science. Woody vines: Stefan Schnitzer from the University of Wisconsin in Milwaukee and colleagues gathered data on the abundance of woody vine growth in American tropical and subtropical forests, and the cascading effects they had on biodiversity and water supply. According to a recent Live Science article, “It’s possible an increase in woody vines could change the nutrient dynamics of forests, in part because of differences between their leaves and the leaves of tropical trees, all of which ultimately fertilize the forest floor.” Read more at “Twisted Tropics: Growth of Vines Imperils Ecosystem.” Ant-mimicking spider: Michael Bok described the jumping spider, Myrmarachne plataleoides, in his blog Anthropoda. At first glance, the spider appears to be a red ant, but upon further examination, the  four pairs of legs become noticeable (see above video). “It makes up for a lack of antennae, and an overabundance of legs, by holding its forelegs up, alongside the head,” he wrote. “Its huge anterior medial eyes are colored to match the head when not viewed directly, and the posterior lateral eyes are enlarged, with darkened pigment around them to mimic an ant’s eyes. Also, the cephalothorax and abdomen are deformed and narrowed considerably.” Read more at...

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From the Community: street lamps, traffic lights and nuclear energy

Songbirds become disoriented by street lamps, plants adapt to the conditions near Chernobyl, a newly discovered spider spins gigantic webs with the strongest known biological material in the world, traffic light experiment shows promise of reducing emissions and easing traffic congestion and researchers discuss the Daily Show with Jon Stewart as an outlet for communication science to the public. Here are some of the latest stories in ecology for the second to last week in September.

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Female jumping spiders fight to the death

Male jumping spiders (Phidippus clarus) size one another up before engaging in a fight—whether the aggression is based on rights to mating or territory—and in many cases, the pre-fight displays are sufficient to deter physical contact. The males do not nest but instead wander between female nests looking for opportunities to mate. The females, on the other hand, are not nomads—they build nests from silk and leaves in which they wait while they draw closer to sexual maturity.

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Protecting the elusive, cave-dwelling troglobites

“Who will speak for the imperiled troglobites? Charismatic megafauna, they are not. Troglobites—not to be confused with troglodytes (cavemen) or trilobites (extinct arthropods)—are neither warm-blooded nor fuzzy. Most are invertebrates, including insects and crustaceans, but there are also troglobitic fish and amphibians—and all are as weird as they are rare.”

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New spider species an homage to David Bowie

Here’s an interesting tidbit for your Friday. A new species of sparassid spider (pictured) from Malaysia has been named after David Bowie. Peter Jäger, an arachnologist at the Senckenberg research institute in Germany, says he named the spider —  Heteropoda davidbowie — after the English rock star in an effort to raise awareness about endangered spiders. Bowie’s 1972 album, The Rise and Fall of Ziggy Stardust and the Spiders from Mars, earned him this honor. It’s tough for spiders to make endangered species lists, Jäger says, so they can use all the publicity they can get. The Guardian reports that there are fewer than 500 individuals of H. davidbowie left in the wild, as its island habitat is cleared for...

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