Earth ChangesS


Bug

Worker Or Queen? Harvester Ant Moms Set Their Daughters' Fates

When it comes to deciding what harvester ant daughters will be when they grow up, mother queens hold considerable sway, according to a new study. The researchers report evidence that eggs are predetermined to become workers or queens from the moment they are lain.

"In honeybees, food determines fate," said Tanja Schwander of Simon Fraser University in Canada. Earlier studies showed that honeybee larvae had the capacity to become either workers or queens, depending upon what the young insects ate.

"Although it had never been shown experimentally, ants had been assumed to be more or less the same," she added. "That's the reason it was surprising to find a strong effect of mother queens."

Stop

2 snowmobilers die in Alaska avalanche

Two snowmobile drivers were killed Friday when they triggered an avalanche and were buried in the snow for nearly an hour, Alaska State Troopers said.

The two were driving their snowmobiles in the backcountry near Turnagain Pass, about 70 miles south of Anchorage, when the avalanche occurred, Troopers spokeswoman Beth Ipsen said.

They were buried for about 45 minutes before being located. Troopers initially reported that three people had died in the avalanche, but the third person was recovered, evaluated by medical professionals at the scene and released, Ipsen said.

Bizarro Earth

Dissolved Organic Carbon From Rivers Can Strongly Impact Arctic Ocean

Arctic rivers transport huge quantities of dissolved organic carbon (DOC) to the Arctic Ocean. The prevailing paradigm regarding DOC in arctic rivers is that it is largely refractory, making it of little significance for the biogeochemistry of the Arctic Ocean. However, a recent study by R. M. Holmes of the Woods Hole Research Center and colleagues at collaborating institutions challenges that assumption by showing that DOC in Alaskan arctic rivers is remarkably labile during the spring flood period when the majority of annual DOC flux occurs.

Bathymetric chart
©NOAA
International Bathymetric Chart of the Arctic Ocean.

Fish

First Map Of Threats To Marine Ecosystems Shows All The World's Oceans Are Affected

As vast and far-reaching as the world's oceans are, every square kilometer is affected by human activities, according to a study in the journal Science by researchers at the University of North Carolina at Chapel Hill and others.

The international team of scientists integrated global data from 17 aspects of global change - from overfishing to global warming - that threaten 20 different marine ecosystems, such as coral reefs and continental shelves. Similar to an online satellite map that lets you add layers of highways, retail stores, schools, parks, etc., to find the most congested areas or the highest concentration of fast food restaurants, the global threat map highlights areas in the ocean where threats overlap.

coral reef degradation
©Unknown
The Science study showed that rising ocean temperatures are the most pervasive threat, and almost half of all the world's coral reefs have recently experienced medium- to high-level impacts.

Butterfly

Colony Collapse Disorder: Researchers Work To Control Varroa Mites, Increase Longevity Of Queen Bees

In response to a fast-spreading syndrome called colony collapse disorder (CCD) that's striking honey bees nationwide, scientists at Agricultural Research Service (ARS) bee laboratories across the country are pooling their expertise. They want to learn what's causing the disappearance of the honey bees that add about $15 billion a year to the value of U.S. crops by pollinating fruit, vegetable, tree nut and berry crops. Some beekeepers have already lost one-half to two-thirds of their colonies to CCD.

bee study
©Peggy Greb
Entomologist Jeffery Pettis assesses the health of bee colonies at the ARS Bee Research Lab in Beltsville, Md.

Fish

Israel: Kinneret fish deliberately poisoned

Tens of thousands of fish found dead in Tiberias marine area. Health and Agriculture Ministries ban fishing until cause of mortality is determined, suspect fishermen might have been responsible for mass poisoning.

The Health and Agriculture Ministries warned the public Saturday no to purchase fish originating from the Tiberias marine, or other lake Kinneret fish bought from unknown sources, following the discovery of thousands of dead fish in the lake.

All fishing in the Kinneret has in the meantime been prohibited, and Health Ministry inspectors have been stationed in the area to enforce the ban.

Ministry teams sent to markets in the region have not found so far any poisoned fish that might have reached the stands. The teams also collected dead fish and transferred them for lab tests, the results of which are not expected before Sunday.

Attention

King penguin faces extinction due to climate change

The prospect that the King penguin will go extinct as a result of climate warming is rising inexorably, scientists say today.

King Penguin
©Yvon Le Maho
King penguin: The study says they at high risk under current global warming conditions

Umbrella

Cities 'are like giant contraceptives'

Cities act like giant contraceptives and could help curb the Earth's explosive population growth that drives climate change, according to two studies.

The United Nations estimates that in the past year the majority of the world's population will, for the first time in human history, live in town and cities.

Cities are now home to half of the world's 6.6 billion humans and by 2030 that urban fraction will rise to 60 per cent as nearly 5 billion people will live in cities of the projected global population of 8.2 billion.

Bizarro Earth

Man's effect on world's oceans revealed



Global human impact map
©BS Halpern
World map showing Man's effect on the planet's oceans

Almost half of the world's oceans have been seriously affected by over-fishing, pollution and climate change, according to a major study of man's impact on marine life.

Evil Rays

Magnitude 5.3 earthquake shakes Middle East

An earthquake shook Lebanon, Israel and the Gaza Strip on Friday, sending panicked people in several towns in the south of Lebanon out on to the streets.

The tremor -- the second in the region this week -- hit at around 1030 GMT, but its intensity was not immediately known.

Friday's quake was felt throughout Lebanon, including the capital Beirut, where many buildings shook.

In the southern coastal city of Tyre, residents ran toward the seashore and began reciting verses of the Koran after the tremor struck, an AFP correspondent witnessed.