March 01, 2010, 2:28 PM EST

By Alex Morales

March 1 (Bloomberg) -- The earthquake that killed more than 700 people in Chile on Feb. 27 probably shifted the Earth's axis and shortened the day, a National Aeronautics and Space Administration scientist said.

Earthquakes can involve shifting hundreds of kilometers of rock by several meters, changing the distribution of mass on the planet. This affects the Earth's rotation, said Richard Gross, a geophysicist at NASA's Jet Propulsion Laboratory in Pasadena, California, who uses a computer model to calculate the effects.

"The length of the day should have gotten shorter by 1.26 microseconds (millionths of a second)," Gross, said today in an e-mailed reply to questions. "The axis about which the Earth's mass is balanced should have moved by 2.7 milliarcseconds (about 8 centimeters or 3 inches)."

The changes can be modeled, though they're difficult to physically detect given their small size, Gross said. Some changes may be more obvious, and islands may have shifted, according to Andreas Rietbrock, a professor of Earth Sciences at the U.K.'s Liverpool University who has studied the area impacted, though not since the latest temblor.

Santa Maria Island off the coast near Concepcion, Chile's second-largest city, may have been raised 2 meters (6 feet) as a result of the latest quake, Rietbrock said today in a telephone interview. He said the rocks there show evidence pointing to past earthquakes shifting the island upward in the past.

"Ice-Skater Effect"

"It's what we call the ice-skater effect," David Kerridge, head of Earth hazards and systems at the British Geological Survey in Edinburgh, said today in a telephone interview. "As the ice skater puts when she's going around in a circle, and she pulls her arms in, she gets faster and faster. It's the same idea with the Earth going around if you change the distribution of mass, the rotation rate changes."

Rietbrock said he hasn't been able to get in touch with seismologists in Concepcion to discuss the quake, which registered 8.8 on the Richter scale.

"What definitely the earthquake has done is made the Earth ring like a bell," Rietbrock said.

The magnitude 9.1 Sumatran in 2004 that generated an Indian Ocean tsunami shortened the day by 6.8 microseconds and shifted the axis by about 2.3 milliarcseconds, Gross said.

The changes happen on the day and then carry on "forever," Benjamin Fong Chao, dean of Earth Sciences of the National Central University in Taiwan, said in an e-mail.

"This small contribution is buried in larger changes due to other causes, such as atmospheric mass moving around on Earth," Chao said.

UPDATED

More on this story here from the NASA website

(The Raw Story: More Americans believe in angels than humans’ role in global warming)

How scary is this?

It's actually quite pretty (again, relatively speaking), but this slug is most likely an Arion rufus, a species that's native to Europe, but has been found in British Columbia and is apparently now also at large in Ontario. Hermaphroditic in nature, some slugs can even knock themselves up, so it only takes a single invader to build an army. Once the population is established, the slugs become (and I quote) the "slow moving lions of the vegetable world."

So how do you get rid of them? The story offers two possibilities. First, you can leave out beer for the slugs. They're attracted to fermented yeast, but they're a little dumb and they can't swim, so they'll end up crawling in and drowning themselves. The other option: Collect the slugs when they come out at night and "immerse them in boiling water." The article, unfortunately, does not mention whether you can then eat Arion rufus in a nice butter sauce.

10 cm Etobicoke Slug a Big, Slimy Mystery in the Toronto Star

(Thanks, Margaret Atwood. Yes, that Margaret Atwood.)

Image taken by Etobicoke, Canada resident Lisa Bendall. Used under fair use.

• 26 October 2009 by Marcelo Aizen and Lawrence Harder

A MOVIE called Vanishing of the Bees opened in cinemas across the UK earlier this month. It's a feature-length documentary about the "mysterious collapse" of the honeybee population across the planet - a phenomenon that has recently attracted a great deal of attention and hand-wringing.

The idea that bees are disappearing for reasons unknown has embedded itself in the public consciousness. It is also a great story that taps into the anxieties of our age. But is it true? We think not, at least not yet.

First, the basics. Pollination by bees and other animals - flies, butterflies, birds and bats - is necessary for the production of fruits and seeds in many wild and cultivated plants. More than 80 per cent of the planet's 250,000 species of flowering plants are pollinated by animals.

Agriculture is a large-scale beneficiary of these pollination services, so claims that pollinators are in decline have triggered alarm that our food supply could be in jeopardy, that we may be on the verge of a global "pollination crisis".

Claims of such a crisis rest on three main tenets: that bees are responsible for the production of a large fraction of our food; that pollinators are declining worldwide; and that pollinator decline threatens agricultural yield. Numerous scientific papers, many media stories and even a European Parliament resolution in 2008 present each of these as an uncontested truth. But are they?

Our analysis of data from the Food and Agriculture Organization of the United Nations reveals a different perspective on the pollination crisis - one that is less catastrophic than that depicted in the movies (Current Biology, vol 18, p 1572, and vol 19, p 915).

The first tenet - that bees are responsible for the production of a large fraction of our food - is simply untrue. Pollinators are important for many crops, but it is a myth that humanity would starve without bees.

Pollinators are important for many crops, but it is a myth that humanity would starve without bees

About 70 per cent of the 115 most productive crops, including most fruits and oilseeds, are animal-pollinated. These account for nearly 2.5 billion tonnes of food a year, about a third of global agricultural production. However, few of these crops depend on animal pollination completely, owing largely to their capacity for self-pollination.

On top of that, production of many staple foods does not depend on pollinators at all: carbohydrate crops such as wheat, rice and corn are wind-pollinated or self-pollinated. If bees disappeared altogether, global agricultural production would decrease by only 4 to 6 per cent.

What of pollinator decline? Claims of global bee disappearance are based on collections of (often extreme) regional examples, which are not necessarily representative of global trends. These examples tend to come from parts of Europe and North America where little natural or semi-natural habitat remains.

Stocks of domesticated honeybees, the most important crop pollinator of all, have also decreased considerably in the US and some European countries in recent decades. However, these declines have been more than offset by strong increases in Asia, Latin America and Africa. Indeed, the number of managed honeybee hives worldwide has increased by about 45 per cent in the past five decades.

There have also been scare stories about "colony collapse disorder" and the spread of Varroa mites in the US and Europe. Again, these are real phenomena, but they are short-term blips rather than the driving forces of long-term trends. Instead, the long-term declines seem to be consistent with the economic dynamics of the honey industry, which seems to be shifting to developing countries in search of cheaper production.

Finally, does a low abundance of pollinators significantly affect agricultural productivity? It is true that a lack of pollinators, especially bees, can limit the yield of many crops and wild plants. It is also true that the yields of many pollinator-dependent crops have grown more slowly than that of most non-dependent crops. However, contrary to what we would expect if pollinators were in decline, the average yield of pollinator-dependent crops has increased steadily during recent decades, as have those of non-dependent crops, with no sign of slowing.

Overall, we must conclude that claims of a global crisis in agricultural pollination are untrue.

Pollination problems may be looming, though. Total global agricultural production has kept pace with the doubling of the human population during the past five decades, but the small proportion of this that depends on pollinators has quadrupled during the same period. This includes luxury foods such as raspberries, cherries, mangoes and cashew nuts. The increased production of these crops has been achieved, in part, by a 25 per cent increase in cultivated area in response to increased demand for them.

This expansion may be straining global pollination capacity, for two reasons. Demand for pollination services has grown faster than the stock of domestic honeybees, and the associated land clearance has destroyed much of the natural habitat of wild pollinators.

The accelerating increase of pollinator-dependent crops therefore has the potential to trigger future problems both for these crops and wild plants. These problems may grow as decreasing yields of raspberries, cherries and the rest prompt higher prices, stimulating yet more expansion of cultivation. So although the current pollination crisis is largely mythical, we may soon have a real one on our hands.

Marcelo Aizen is a researcher at the National Scientific and Technical Research Council of Argentina

Lawrence Harder is a professor of pollination ecology at the University of Calgary in Alberta, Canada

How green is your pet?

• 23 October 2009 by Kate Ravilious

SHOULD owning a great dane make you as much of an eco-outcast as an SUV driver? Yes it should, say Robert and Brenda Vale, two architects who specialise in sustainable living at Victoria University of Wellington in New Zealand. In their new book, Time to Eat the Dog: The real guide to sustainable living, they compare the ecological footprints of a menagerie of popular pets with those of various other lifestyle choices - and the critters do not fare well.

As well as guzzling resources, cats and dogs devastate wildlife populations, spread disease and add to pollution. It is time to take eco-stock of our pets.

To measure the ecological paw, claw and fin-prints of the family pet, the Vales analysed the ingredients of common brands of pet food. They calculated, for example, that a medium-sized dog would consume 90 grams of meat and 156 grams of cereals daily in its recommended 300-gram portion of dried dog food. At its pre-dried weight, that equates to 450 grams of fresh meat and 260 grams of cereal. That means that over the course of a year, Fido wolfs down about 164 kilograms of meat and 95 kilograms of cereals.

It takes 43.3 square metres of land to generate 1 kilogram of chicken per year - far more for beef and lamb - and 13.4 square metres to generate a kilogram of cereals. So that gives him a footprint of 0.84 hectares. For a big dog such as a German shepherd, the figure is 1.1 hectares.

Meanwhile, an SUV - the Vales used a 4.6-litre Toyota Land Cruiser in their comparison - driven a modest 10,000 kilometres a year, uses 55.1 gigajoules, which includes the energy required both to fuel and to build it. One hectare of land can produce approximately 135 gigajoules of energy per year, so the Land Cruiser's eco-footprint is about 0.41 hectares - less than half that of a medium-sized dog.

The Vales are not alone in reaching this conclusion. When New Scientist asked John Barrett at the Stockholm Environment Institute in York, UK, to calculate eco-pawprints based on his own data, his figures tallied almost exactly. "Owning a dog really is quite an extravagance, mainly because of the carbon footprint of meat," he says.

Eco-pawprints

Then there are all the other animals we own. Doing similar calculations for a variety of pets and their foods, the Vales found that cats have an eco-footprint of about 0.15 hectares (slightly less than a Volkswagen Golf), hamsters come in at 0.014 hectares apiece (buy two, and you might as well have bought a plasma TV) and canaries half that. Even a goldfish requires 0.00034 hectares (3.4 square metres) of land to sustain it, giving it an ecological fin-print equal to two cellphones.

This kind of analysis appeals to David Mackay, a physicist at the University of Cambridge and the UK government's new energy adviser. He believes we should put as much thought into choosing a pet as we do into buying a car. "If a lifestyle choice uses more than 1 per cent of your energy footprint, then it is worthwhile reflecting on that choice and seeing what you can do about it," he says. "Pets definitely deserve attention: by my estimates, the energy footprint of a cat is about 2 per cent of the average British person's energy footprint - and it's bigger for most dogs."

Alternatively, consider the cumulative environmental impact of our furry friends. The US, which tops the list for both cat and dog ownership in absolute terms, is home to over 76 million felines and 61 million canines. Taking the estimated cat population for the top 10 cat-owning countries, the Vales calculate that the land required just to feed these cats is over 400,000 square kilometres. That's equivalent to one-and-a-half times the area of New Zealand. A further five New Zealands are required to feed the pooches living in the top 10 dog-owning countries - which, perhaps surprisingly, does not include the UK.

Then there are the other environmental impacts of pets. Every year, for example, the UK's 7.7 million cats kill over 188 million wild animals (Mammal Review, vol 33, p 174). That works out at about 25 birds, mammals and frogs per cat. Similar figures have emerged from surveys in the US and Australia. There is also a knock-on effect because cats feasting on wildlife can leave wild predators such as hawks and weasels short of food.

Every year the UK's 7.7 million cats kill over 188 million wild animals. That's 25 per cat

Dogs are not entirely blameless either. In 2007, Peter Banks and Jessica Bryant from the University of New South Wales in Sydney, Australia, monitored bird life in woodlands just outside the city to assess the impact of dogs being walked there (Biology Letters, vol 3, p 611). They showed that bird life in areas frequented by dogs, even when kept on a lead, had 35 per cent less diversity and 41 per cent fewer birds overall. Areas with off-lead dogs seem to suffer even more: ongoing studies in the UK indicate that dogs are aiding the decline of some rare species of bird, such as European nightjars (Ibis, vol 149, p 27).

Another major environmental problem, particularly in urban areas, is pet faeces. A study carried out in Nashville, Tennessee, indicated that it is a significant cause of high bacterial levels in local rivers and streams, particularly after heavy rain. As well as making the water unsafe to drink, high bacterial levels can starve waterways of oxygen and kill aquatic life.

Cat excrement is particularly toxic. In 2002, it emerged that sea otters along the Californian coast are dying from a brain disease caused by Toxoplasma gondii. The parasite, which is found in cat faeces, ends up in rivers and estuaries thanks to cat owners who flush their cat litter down the toilet or allow their cats to defecate outside. Dolphins and whales are also affected(newscientist.com/article/dn14037).

So what is an eco-friendly animal lover to do? If you already have a pet, then changing its diet can help. Meat is the key, since its production is so energy-intensive. You can almost halve the eco-pawprint of your dog simply by feeding it many of the same sort of savory foods that you eat, which are likely to be far less protein-rich than most dog foods. As well as quantity, think about quality. "If pussy is scoffing 'Fancy Feast' - or some other food made from choice cuts of meat - then the relative impact is likely to be high," says Robert Vale. "If, on the other hand, the cat is fed on fish heads and other leftovers from the fishmonger, the impact will be lower."

Dog owners might also want to avoid walking their dog in wildlife-rich areas, and cat owners could consider keeping Tiddles indoors. "Cats are nocturnal, so the single most important thing people can do to reduce predation is to keep cats in at night," says Michael Woods of the Mammal Society in Southampton, UK.

And if you are thinking of acquiring a pet? "Shared pets are the best - the theatre cat or the temple dogs," says Robert Vale. But if you must own your own, think about getting an animal that serves a dual purpose. He recommends hens, which partly compensate for their eco-footprint by providing eggs. Or there is an even better alternative, if you can stomach it. "Rabbits are good," he says, "provided you eat them."

Kate Ravilious is a science journalist based in York, UK, and the guilty owner of a medium-sized dog