Earth ChangesS


Bug

Ants Use Bacteria to Make Their Gardens Grow

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© University of Wisconsin-MadisonThese leafcutter ants are located on a spongy fungus garden, which they grow themselves.
Leaf-cutter ants, which cultivate fungus for food, have many remarkable qualities.

Here's a new one to add to the list: the ant farmers, like their human counterparts, depend on nitrogen-fixing bacteria to make their gardens grow. The finding, reported Nov. 20 in the journal Science, documents a previously unknown symbiosis between ants and bacteria and provides insight into how leaf-cutter ants have come to dominate the American tropics and subtropics.

What's more, the work, conducted by a team led by University of Wisconsin-Madison bacteriologist Cameron Currie, identifies what is likely the primary source of terrestrial nitrogen in the tropics, a setting where nutrients are otherwise scarce.

"Nitrogen is a limiting resource," says Garret Suen, a UW-Madison postdoctoral fellow and a co-author of the new study. "If you don't have it, you can't survive."

Bizarro Earth

6.8 Earthquake Recorded Near Tonga

A powerful earthquake of magnitude 6.8 struck northeast of the South Pacific island nation of Tonga on Tuesday, the United States Geological Survey said, but a destructive tsunami was not expected.

The quake's epicenter was recorded 195 km (120 miles) east-northeast of the Tongan capital Nuku'Alofa at a depth of 61 km (38.5 miles), it said.

There were no immediate tsunami warnings issued, according to websites for the USGS and the Hawaii-based Pacific Tsunami Warning Center (PTWC).

"Based on all available data, a destructive Pacific-wide tsunami is not expected and there is no tsunami threat to Hawaii," the PTWC said in a statement.

Newspaper

New Zealand: Hive Thieves Rustle Over a Million Bees

Thieves have rustled more than million bees from a Matamata beekeeper.

John Tyler lost 28 hives, and their 1.125 million industrious inhabitants, in the November 7 or 8 robbery from a Te Poi farm paddock, the Matamata Chronicle reported.

Each hive contained about 50,000 bees, weighed 25 kilograms and was worth about $7500.

The robbery of his winged workers, requiring at least two men and a truck, has left a bitter taste in Mr Tyler's mouth.

The hives were not insured.

"(I'm) stunned, I suppose. I'm pretty upset," he told the newspaper.

The beekeeper was coming into the busiest part of his year, with fruitgrowers needing his bees to pollinate their plants.

Bizarro Earth

El Nino intensifies Latin America drought

From a devastating food crisis in Guatemala to water cuts in Venezuela, El Nino has compounded drought damage across Latin America this year.

The occasional seasonal warming of central and eastern Pacific waters upsets normal weather patterns across the globe and occurs on average every two to five years. Typically lasting around 12 months, El Nino reappeared once again in June.

Guatemalan authorities blamed it for the nation's worst drought in 30 years, which has left almost 500 people dead from hunger since the start of the year. Around 36,000 hectares (90,000 acres) of corn and bean crops were lost, officials said.

Bizarro Earth

5.1 Earthquake Jolts Mexico Pacific Coast

An earthquake measuring 5.1 on the Richter scale struck Jalisco, a state on Mexico's Pacific coast on Monday, the state-run National Seismology Service said.

It was recorded 8 minutes and 41 seconds after midnight as was 192 kilometers (km) southwest of Cihuatlan, a town in Jalisco. There have been no reports so far of harm to people or damage to property.

The quake was 30 km deep and was located at 18.05 degrees north and 105.88 degrees west in longitude. The U.S. Geological Survey reported the magnitude as 5.2.

Frog

New Chameleon Species Discovered in East Africa

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© University of YorkKinyongia magomberae (the Magombera chameleon)
Dr Andrew Marshall, from the Environment Department at the University of York, first spotted the animal while surveying monkeys in the Magombera Forest when he disturbed a twig snake eating one.

The specimen was collected, tested and compared to two others found by scientists in the same area and has now been named Kinyongia magomberae (the Magombera chameleon) in research published in the African Journal of Herpetology.

Dr Marshall is co-author of the study alongside researchers from the Museo Tridentino di Scienze Naturali, the South African National Biodiversity Institute, Anglia Ruskin University and the University of Stellenbosch.

Fish

Sea Stars Bulk Up to Beat the Heat

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© Nancy SeftonOchre sea stars (Pisaster ochraceus) are voracious predators in the intertidal zone. Feeding on mussels and other mollusks, they limit the range of these species.
A new study finds that a species of sea star stays cool using a strategy never before seen in the animal kingdom. The sea stars soak up cold sea water into their bodies during high tide as buffer against potentially damaging temperatures brought about by direct sunlight at low tide.

"Sea stars were assumed to be at the mercy of the sun during low tide," said the study's lead author, Sylvain Pincebourde of François Rabelais University in Tours, France. "This work shows that some sea stars have an unexpected back-up strategy."

The researcher is published in the December issue of The American Naturalist.

Sea stars need to endure rapid changes in temperature. During high tide, they are fully submerged in cool sea water. But when tides receded, the stars are often left on rocky shorelines, baking in the sun.

Cloud Lightning

England: 'Rain like this happens once every 1,000 years'



The full and devastating impact of England's worst recorded day of rain was still emerging last night as tributes were paid to a policeman swept away by floodwaters while trying to save others.

PC Bill Barker was helping motorists stranded on a bridge over the Derwent in the Cumbrian town of Workington when it collapsed. His body was discovered hours later on a nearby beach.

The Environment Agency said that the flooding across the region was so severe that such an event was likely to happen only once in 1,000 years. The rainfall, on to an already saturated terrain, was the highest level measured in England since records began. Meteorologists recorded 314mm (12in) of rain in 24 hours and flood warnings remained in place across the North West of England, parts of Wales, Scotland and Northern Ireland.

Bizarro Earth

Colombia volcano eruption subsides, evacuation continues

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© Channel News Asia File PictureGaleras volcano
A volcanic eruption has eased enough to allow a local airport to open, but thousands of people are staying clear of Colombia's most active volcano as more activity is feared, authorities warned on Sunday.

Ashes are still falling near the Galeras volcano in the south, after Friday's eruption, but a colour-coded alert has been lowered from red to orange, the Colombia Institute of Geology and Mining (Ingeominas) said.

An orange alert means a new eruption was possible "in days or weeks," rather than imminently, it added.

Friday's eruption caused no casualties, but some 1,000 people were evacuated from around the volcano to Pasto, the capital of Narino department.

Another 8,000 people defied evacuation orders, refusing to leave their homes.

Authorities are urging people living in the Galeras foothills to leave for Pasto, 920 kilometres south of Bogota, as the danger of new eruptions is still quite high, warned Ingeominas deputy director Martha Calvache.

Better Earth

East Antarctic Ice Sheet May Be Losing Mass

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© UnknownThe mass loss is probably driven by processes occurring on the coast.
The East Antarctic ice sheet has been losing mass for the last three years, according to an analysis of data from a gravity-measuring satellite mission.

The scientists involved say they are "surprised" by the finding, because the giant East Antarctic sheet, unlike the west, has been thought to be stable.

Other scientists say ice loss could not yet be pinned on climate change, and uncertainties in the data are large.

The US-based team reports its findings in the journal Nature Geoscience.

The data comes from Nasa's Gravity Recovery and Climate Experiment (Grace) mission.

Grace has previously shown that the smaller West Antarctic and Greenland ice sheets are losing mass.