Earth ChangesS


Bug

Ants Are Friendly to Some Trees, But Not Others

Tree-dwelling ants generally live in harmony with their arboreal hosts. But new research suggests that when they run out of space in their trees of choice, the ants can get destructive to neighboring trees.

The research, published in the November issue of the American Naturalist, is the first to document that ants bore into live trees, and it reopens a centuries-old debate on the relationship between ants and plants.

Ants and certain species of plants and trees have cozy relationships. Myrmecophytes, also knows as ant-plants, have hollow stems or roots that occur as a normal part of their development. Ant colonies often take residence in these hollows. To protect their homes, the ants patrol the area around the tree, killing insects that want to eat the plant's leaves and sometimes destroying vegetation of other plants that might compete for precious soil nutrients and sunlight. The relationship is a classic biological mutualism. The ants get a nice place to live; the trees get protection. Everybody wins.

Better Earth

Picking up mates at the white shark café

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© Tom Campbell/SplashdownDirect/Rex FeaturesMeet me at the great white café
Great whites aren't all alike. Even though the sharks travel all over the Pacific Ocean to hunt, they tend to mate with others from the same area, forming genetically distinct groups.

That's what local great whites revealed to Barbara Block of Stanford University in California and her colleagues. The team headed out into the Pacific to find the sharks, which they lured to the surface using a silhouette of a seal. They then used a pole to attach two different tags to the sharks and took a sneaky biopsy at the same time. See the biologists tagging white sharks here.

GPS tags were used to track the long-distance movements of the creatures, allowing the team to follow their migration during the colder months from coastal areas to the deep ocean. The other tags gave off sonic "pings" that were picked up by sensors moored in coastal areas, providing more precise location fixes than the satellite measurements, so that the team could tell if the sharks returned to the same areas.

Bizarro Earth

Quakes from the 1800s still shaking planet

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© USGSMoment Magnitude, Mw 7.9 USGS NEIC (WDCS-D)
Some earthquakes can leave a legacy of aftershocks that last for centuries.

Low-level seismic rumbles appear to foreshadow many quakes. Yet not always: the 2008 Sichuan quake in China came out of the blue. These rumbles may not be precursors but aftershocks - readjustments at a fault following a larger event, in some cases centuries earlier.

Seth Stein of Northwestern University in Evanston, Illinois, and colleagues analysed the rate of fault slip in various tectonic settings. At plate boundaries, motion rapidly "reloads" a fault with new stress and changes conditions there, so tremors that can be clearly identified as aftershocks typically end within a decade, they found. Far away from plate boundaries, however, fault reloading is much slower, and aftershocks can continue for hundreds of years. The New Madrid fault in Missouri, for instance, may be experiencing aftershocks from a quake in the early 1800s (Nature, DOI: link).

Heart - Black

Midway: Message from the Gyre

These photographs of albatross chicks were made just a few weeks ago on Midway Atoll, a tiny stretch of sand and coral near the middle of the North Pacific. The nesting babies are fed bellies-full of plastic by their parents, who soar out over the vast polluted ocean collecting what looks to them like food to bring back to their young. On this diet of human trash, every year tens of thousands of albatross chicks die on Midway from starvation, toxicity, and choking.

To document this phenomenon as faithfully as possible, not a single piece of plastic in any of these photographs was moved, placed, manipulated, arranged, or altered in any way. These images depict the actual stomach contents of baby birds in one of the world's most remote marine sanctuaries, more than 2000 miles from the nearest continent.

Bizarro Earth

Two Earthquakes Strike Taiwan Island

Two earthquakes measuring 5.9 and 5.4 on the Richter Scale struck the central part of Taiwan island. They were felt across Taiwan. The cities of Fuzhou and Xiamen in the Chinese mainland's Fujian Province and Hong Kong also felt the tremors.

The earthquakes are the worst to hit Taiwan in ten years. The epicenter was in Nantou County, about 200 kilometers south of Taipei, with a depth of 7 and 6 kilometers respectively. The tremors reminded Nantou residents of the September 21st quake in 1999.

A local resident of Nantou County said, "I was scared. I was the victim of the September 21st earthquake. That earthquake damaged our houses. So I ran out of the house immediately after I felt it shake. I was sitting there, and ran out immediately."

Many residents tried to make phone calls to their family and friends but communications had been cut off.

Bizarro Earth

China: 909,000 Hit by Drought

A drought since September had affected 909,000 people in east China's Jiangxi Province, a spokesman for the provincial flood control and drought relief office said yesterday.

The drought had cut off normal water supplies in some rural areas. "Villagers in Fengxin, Jing'an and Leping counties have to carry drinking water by trucks," said Sun Xiaoshan, deputy director of the office.

"The water levels of four of the province's five main rivers hit record lows and are still dropping.

"The self-cleaning ability of rivers has decreased significantly due to the drastic fall of volume, posing a threat to public health."

The provincial government had stepped up monitoring and supervision over enterprises that may cause pollution, Sun added.

Bizarro Earth

Snow Cap Disappearing from Mount Kilimanjaro

The snows of Kilimanjaro may soon be gone. The African mountain's white peak - made famous by writer Ernest Hemingway - is rapidly melting, researchers report.

Some 85 percent of the ice that made up the mountaintop glaciers in 1912 was gone by 2007, researchers led by paleoclimatologist Lonnie Thompson of Ohio State University report in Tuesday's edition of Proceedings of the National Academy of Sciences.

And more than a quarter of the ice present in 2000 was gone by 2007.

If current conditions continue "the ice fields atop Kilimanjaro will not endure," the researchers said.

The Kilimanjaro glaciers are both shrinking, as the ice at their edges melts, and thinning, the researchers found.

Roses

Fluorescence Found to Aid Healing in Corals

Glow
© Caroline V. Palmer
Injured corals develop colorful glowing "scabs" to help themselves heal, a new study has found.

When a coral is broken or wounded, it releases highly reactive atoms of oxygen known as free radicals to close up the gashes.

But these powerful molecules can also inadvertently kill off some of the coral's healthy cells. Hydrogen peroxide, for instance, is a common free radical in corals, and it can damage every part of the cell, from DNA to proteins.

Hurt corals have also been known to take on brightly colored glows, noted study leader and coral immunologist Caroline Palmer. Wounds on Acropora millepora corals appear blue, for example, while injured tissues on Porites species - like the raised and swollen patches seen above - are an "intense" bubble-gum pink.

Magnify

Man-Eating Lions Consumed 35 People in 1898

Lions
© AP Photo/Charles Rex ArbogastTwo world renowned man-eating Tsavo lions are seen stuffed and on display at Chicago's Field Museum of Natural History Monday, Nov. 2, 2009.
The nightly attacks by two man-eating lions terrified railway workers and brought construction to a halt in one of east Africa's most notorious onslaughts more than a hundred years ago. But the death toll, scientists now say, wasn't as high as previously thought.

Over nine months the two voracious hunters claimed 35 lives - no small figure, but much less than some accounts of as many as 135 victims.

It was 1898, when laborers from India and local natives building the Uganda Railroad across Kenya became the prey for the pair, a case that has been the subject of numerous accounts and at least three movies.

The death toll had been estimated at 28 railway workers and "scores of unfortunate African natives," with the total ranging as high as 135. Delay of the railroad was even subject to debate in Britain's House of Commons.

Igloo

Taking the Earth's temperature

The public is finally catching on to the fact that the global-warming scare is driven far more by ideology than science, and a recent Gallup poll revealed that the percentage of Americans who think the threat of global warming is exaggerated is at its highest level ever.

Pat Michaels (Ph.D. in climatology), a senior fellow at the Cato Institute and retired research professor of environmental sciences at the University of Virginia, relates how the spokesperson for an organization with some of the oldest temperature-sensor data in existence refused to share it with other scientists, saying, "Why should we make the data available when their aim is to try and find something wrong with it?" Whoa, there, Nellie! Did you grasp the outrageousness of that statement? If not, take a moment to reread it for its breathtakingly anti-scientific thrust.