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Some of the emerging solutions for the world’s energy woes are outlined in a series of reports appearing in the current issue of the journal Science. Usually, Science’s articles are available only by purchasing the magazine, or looking it up at the library. But Science’s editors at the American Association for the Advancement of Science believe the energy issue rates so highly in the public interest that they’re making the reports in their special section freely accessible for the next two weeks. (Free registration is required to access some of the reports.)
A very good snapshot of where we are today and where we are headed in terms of green and not so green energy. One of oil’s biggest and most promising green rivals are Concentrated-solar-power (CSP) facilities like the multibillion-dollar Desertech which is being built in both Africa and the Middle-East, eventually to provide power to Europe’s electric grid. California currently has the Sierra Sun Tower CSP. These projects are not without trade-offs. The SST project is on private land, but SST and future projects will impact wildlife, habitat and recreational use. CSPs also provide hydrogen as a by-product which can be used for fuel. The mental light is switching on for the government – which financed some initial research – which is backing out of the push for cellulosic ethanol as a fuel. On the other hand – for better or worse – research proceeds on algae-based biofuels. Wind power is progressing, but there is some resistance. In this report the major obstacle is the not in my backyard sentiment. Those that do not have the time to register and read the full report at Science might find the MSNBC report a helpful and relatively painless summary.
‘Zombie ants’ controlled by parasitic fungus for 48m years
The finding shows that parasitic fungi evolved the ability to control the creatures they infect in the distant past, even before the rise of the Himalayas.
The fungus, which is alive and well in forests today, latches on to carpenter ants as they cross the forest floor before returning to their nests high in the canopy.
The fungus grows inside the ants and releases chemicals that affect their behaviour. Some ants leave the colony and wander off to find fresh leaves on their own, while others fall from their tree-top havens on to leaves nearer the ground.
The final stage of the parasitic death sentence is the most macabre. In their last hours, infected ants move towards the underside of the leaf they are on and lock their mandibles in a “death grip” around the central vein, immobilising themselves and locking the fungus in position.
“This can happen en masse. You can find whole graveyards with 20 or 30 ants in a square metre. Each time, they are on leaves that are a particular height off the ground and they have bitten into the main vein before dying,” said David Hughes at Harvard University.
One of the researchers remarks “The question now is, what are the triggers that push a parasite not just to kill its host, but to take over its brain and muscles and then kill it.” What eventually kills the ant is the alkaloid chemicals from the fungus. The fossil they observed which showed the “death grip” markings of an infected ant was about 48 million years old. One can imagine an evolutionary scenario that began with the ants simply being infected. They died and those which died in the best places on the forest floor perpetuated the fungus. A very hit and miss method, but worked well enough for the fungus species to survive. At some point the fungus that changed behavior was highly selected because it became the variant which produced the highest population of fungus.
‘Terror bird’ used its skull and beak to pick at its prey, scientists say
From the size and shape of the beak, researchers have always known that the massive South American “terror bird” was a predator. Now they know precisely how the bird killed — wielding its huge skull and hooked beak like an pickax and repeatedly chopping at prey until it succumbed.
The 5-foot-tall, 90-pound Andalgalornis steulleti, whose skull was nearly twice the size of a human’s, went extinct millions of years ago, but Argentine and U.S. researchers have been using CT scans and biomechanical reconstructions to deduce how the flightless predators killed.
The Andalgalornis lived in what is now the northwestern Argentina about 6 million years ago. Thus far it is known they were part of a taxonomic family of at least 18 species. The largest of the family of phorusrhacids or ‘terror birds’ was the Kelenken which was 10′(3 meters) tall.
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