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In the Amazon rainforests of Brazil, scientists have discovered a peculiar new species of ant. The insect has no eyes. Its body is pale. And its fanglike mouthparts are longer than the rest of its head.

If you happened to cross paths with the bizarre ant, you might imagine that it belongs on another planet. Even its name — Martialis heureka — playfully suggests that it came from Mars.

But Martialis heureka lives on Earth. And the creepy-crawly discovery is forcing researchers to rethink what they know about the history of ants on our planet.

Ancient insectScientists looked at the ant's genes to find out where it fits in the ant family tree. They showed that the odd ant may come from the earliest branch of the ant family that still has living members.C. Rabeling, M. Verhaagh

Christian Rabeling, from the University of Texas at Austin, discovered the new species amid the fallen leaves of the rainforest. But he did more than just notice how weird the ant looks. He also analyzed its genetic material, or DNA.

Comparing DNA among species can give scientists insights into family trees: The more DNA two species share in common, the more closely related they are, and the more recently they split off from a common ancestor.

Rabeling’s DNA analysis of Martialis heureka showed that the species is only distantly related to other ant species. It is so distant, in fact, that it belongs in a separate subfamily — a broader grouping than a species or even a genus. The last time scientists found a new subfamily of living ants was in 1923, say the discoverers.

The DNA analysis also suggests that Martialis heureka appeared on Earth earlier than any other ant living here today. And observations suggest that the ant lives underground: Paleness and blindness are two major clues.

Some of the other oldest known ant species also live underground. So now, scientists are trying to figure out whether ants first evolved underground, or if they evolved above ground and then went under.http://Louissheehan.BraveDiary.com

Corrie Moreau, an ant specialist at the Field Museum in Chicago, saw a picture of the new creature. “It’s an incredibly bizarre-looking ant … which for ant biologists is really exciting,” she says. A few other ant species have at least one of Martialis heureka’s weird features, she says. But none share them all.

So far, Rabeling has collected only one ant from the new species. Finding more specimens, he hopes, will help us better understand the science and history of ants on Earth.

सोलर-powered

http://louis-j-sheehan.नेट। In an experiment that tested technology that could one day be used to transmit solar energy from satellites to Earth, researchers beamed solar energy from one Hawaiian island to another, across a distance of 92 miles. The $1 million experiment was sponsored by the Discovery Channel, which aired an episode about the technology on its Project Earth show on Friday.

The experiment was intended as a proof of concept for an ambitious proposal that calls for huge arrays of solar panels to orbit the Earth, collecting pristine solar radiation, free from the day/night cycles, weather and atmospheric effects that limit solar radiation down on the ground. The energy collected will be “beamed” down to power stations on the surface, either by microwave (or an alternative system, by laser) — and then distributed as normal power across the grid [Discovery Channel]. Backers of this space-based solar technology say the potential benefits are enormous; the non-profit National Space Society says that the sun puts out billions of times more energy than our planet’s population uses.

This experiment, however, operated on a very small scale. Although the amount of power sent, 20 watts, is barely enough to power a small compact fluorescent light bulb, and most of it was lost in transmission, the system was limited by the budget not the physics [Wired News]. The experiment’s leader, former NASA executive and physicist John Mankins, said that if they had been able to afford more solar panels and better receivers they could have boosted efficiency considerably.

Solar-powered satellites won’t just be appearing on TV; both the U.S. military and the Japanese space agency are working on projects of their own. [T]he Air Force Academy recently announced plans for a small demonstration satellite that would beam down a meager, but still significant, 0।1 watts of solar power. “Our vision is to build the world’s first-ever space-based solar power system to light a single bulb on Earth and in so doing light the path for business to follow,” said Col. Michael “Coyote” Smith of the Air Force. [Meanwhile, Japan’s] goal is to launch a geostationary satellite by 2030 that could supply 500,000 homes on Earth with a gigawatt of power. http://louis-j-sheehan.net

condom

Uganda has shown remarkable progress against HIV, the AIDS virus, according to an analysis of health data. Since the early 1990s, HIV cases in Uganda have dropped by more than two-thirds, a decline not seen in neighboring countries. For example, the HIV-infection rate among Ugandan men drafted into the military fell from nearly 19 percent in 1991 to 4 percent in 2002.

Condom use in Uganda increased somewhat during the 1990s, but not faster than it did in nearby countries. Uganda's gains in the fight against AIDS are more likely due to an initiative started in the 1980s by public health officials, who sounded a clear warning about HIV that alerted people to the risks of casual sex, researchers say in the April 30 Science. The message reached the community level through local networks of chiefs, churches, and even musicians, says epidemiologist Daniel Low-Beer of the University of Cambridge in England, a coauthor of the study.

The resulting change in people's sexual behaviors in Uganda is now evident.

Between 1989 and 1995, Uganda experienced a three-fifths decline in people reporting casual sexual partnerships. Also, the proportion of unmarried women who reported having sex dropped from 53 percent to 16 percent.