Bugs go dead with Coke

A skull and crossbones would be the last thing you would find on a can of Coca-Cola, but farmers in India are using it to replace poisons that do. Looking to save a few rupees, farmers in Andrah Pradesh and Chattisgarh states have taken to spraying cotton and chili fields with The Real Thing.

Gotu Laxmaiah, a farmer from Ramakrishnapuram in Andra Pradesh, said he was delighted with his new cola spray, which he applied this year to several hectares of cotton. "I observed that the pests began to die after the soft drink was sprayed on my cotton," he told the Deccan Herald newspaper.

The main reason why Coke has become popular for use as a pesticide is cost. Traditional pesticides cost around 10,000 rupees per liter, but a liter and half of Coke costs only 30 rupees. While there is no scientific proof of Coke's effectiveness as a pesticide, analysts suggest sugar in the cola attracts red ants that feed on insect larvae. I guess Diet Coke might not kill like the Real Thing... although other farmers say Pepsi and local soft drinks are just as effective.

It is not known who was the first Indian farmer to use Coke as a bug killer, but I may have a reason why they tried. In August of last year, independent testing of soft drinks bottled in India found pesticide levels significantly higher than European Economic Commission limits.

The foundation of Roman skin care

Archaeologists discovered a sealed Roman pot containing a white cream during a July 2003 dig at an ancient Roman temple complex in London. The discoverers guessed that the material could have been some sort of toothpaste or a pharmaceutical product. But after analyzing the cream, it was revealed the components were basically starch, animal fat, and tin oxide. They believe the mixture was used as a skin cream and is not unlike modern cosmetic foundation. One of the researchers said rubbing the cream on his hand completely concealed a scar on his knuckle. The cream, which dates to around 150 BC, was probably just as effective and a lot cheaper than similar cosmetics made today.

Natural nuclear reactor secrets are revealed

Modern nuclear reactors are complex beasts with elaborate cooling systems, precisely composed and controlled fuel and control material. But nuclear reactors don't have to be human-made at all. In the 1970s scientists noticed that uranium samples taken from the Oklo mines in Gabon, West Africa contained only half the amount of U-235 that was expected. The then determined the only other uranium samples that had the same level of U-235 came from used nuclear fuel in modern reactors. Researchers concluded that 1.7 billion years ago, the material at Oklo had a high enough concentration of U-235 to permit nuclear fission.

But how did this nuclear reactor work, and why didn't the reaction run uncontrolled until it blew up? Researchers from the Washington University in St. Louis analyzed xenon found in the rocks of the Oklo reactors and determined the reactor worked on a cycle similar to that of a geyser. The reactor had a 30 minute nuclear reaction cycle followed by two and a half hours of dormancy.

In the Oct. 29, 2004 issue of Physical Review Letters, Meshik and his Washington University collaborators write: "This similarity (to a geyser) suggests that a half an hour after the onset of the chain reaction, unbounded water was converted to steam, decreasing the thermal neutron flux and making the reactor sub-critical. It took at least two-and-a-half hours for the reactor to cool down until fission Xe (xenon) began to retain. Then the water returned to the reactor zone, providing neutron moderation and once again establishing a self-sustaining chain."

It is estimated that the natural reactors at Oklo cycled on and off at an average power of 100 kilowatts for 150 million years. The research also may help solve the problem of nuclear waste disposal. The xenon gas produced in the reactor would have been expected to have escaped as soon as it was produced, but instead it appears to have been incorporated into alumophosphate at the site. The workings of the Oklo reactors may provide clues on how gases produced in modern reactors can be captured into similar materials.

Nature unearths once lost land

Spurred by efforts to inhabit dry parts of the West, US engineers used dams to create stockpiles of water in arid regions. In the case of the Glen Canyon dam, the Colorado River flow was impeded and water backed up 186 miles to form Lake Powell. The lake's creation filled canyons that were once passable on foot and environmentalists saw many natural treasures lost. But 40 years after the Glen Canyon dam was built, drought is helping nature reclaim those lost treasures (registration required). Since 1999, Lake Powell has lost more than 60 percent of its water. As the water recedes, many of the once inundated side canyons are now allowing a new generation to see what older family members thought was lost forever.

Glen Canyon has been called a lost Eden, largely because the conditions are perfect for life. The side canyons, with deep shade and sculptured grottoes, were always the ecological pump for much of the life in the Grand Canyon and beyond, Dr. Wegner [an expert on canyon ecology] said. Last spring Mr. Peterson [executive director of the Glen Canyon Institute] and his colleagues began leading small groups down the Escalante River to see the recovery firsthand. This fall, trekkers can walk 15 miles downriver, barefoot, marveling at the sights, sounds and smells.

The change may become permanent. According to a hydrologic expert, users are consuming 1.5 million acre-feet of water more than what flows into the lake and without several back-to-back years of high river runoff, Lake Powell may never be full again.

New discoveries on evolution of the eyes and nose

Fish have two external nostrils on each side of the head that allow them to smell. Humans have one external nostril on each side of the head, and another that opens to the throat that allows us to smell and breathe. But how did the nostrils evolve from what the fish has to what the human has? Paleontologists have discovered an ancient fish fossil that captures this nostril transition in action.

Kenichthys has a back nostril that is located right on the lip, separating the two-toothed upper jawbones, the maxillan and the premaxillan. (It is as if we were to have a nostril in a gap between our front teeth and our canine teeth.) In other words, it constitutes a perfect halfway point in the nostrils migration from the face to the palate, and moreover this halfway point is the precisely the one that some scientists have regarded as an anatomical impossibility. Unfortunately the ?cord? of nerves and blood vessels has not been preserved in Kenichthys, but since it normally runs from the maxillan to the premaxillan, it must either have been cut off or relegated to another position. What was considered impossible was apparently possible after all.

Switching to the subject of eyes, research published in last week's Science magazine helps unravel the evolutionary origin of the eye.

Researchers in the laboratories of Detlev Arendt and Jochen Wittbrodt [from the European Molecular Biology Laboratory] have discovered that the light-sensitive cells of our eyes, the rods and cones, are of unexpected evolutionary origin ? they come from an ancient population of light-sensitive cells that were initially located in the brain.

The group studied a marine worm which had brain cells that remarkably looked similar to the human eye's rods and cones, and believed they may have the same evolutionary origins. Then using molecular fingerprints they determined the molecule opsin (a light-sensitive molecule) in the worm was remarkably similar to the opsin found in vertebrate rods and cones. To the researchers, this meant humans and the worm shared a common ancestor, and from that ancestor the light sensitive cells in its brain eventually evolved onto today's human eyes. If you can catch Hannibal around, ask him how all of this fits into the creationism versus evolution argument.

November is raining bullets: