With glasses, contacts, and LASIK surgery, most of us nearsightedness folks don’t have to worry about squinting at the blackboard anymore. But the sheer prevalence of nearsightedness, or myopia, among Asian schoolchildren (in Singapore, China, Taiwan, Hong Kong, Japan, and Korea) is stunning: 80 to 90% according to a recent review in the journal Lancet. In comparison, that number is just 20 to 30% in the UK. Myopia has also been on the rise in both Asia and Europe over the past few years.
While there are genes linked to myopia, its rising prevalence in both continents points to environmental causes. Namely, kids are spending more time hunched over screens and books instead of playing outdoors. In myopia, light coming into the eye can no longer focus at the retina because the eyeball has become too long. A body of research in humans and animals suggest that reading at close distances and lack of bright sunlight could cause elongated eyeballs.
The state of our forests is troubled, but maybe on the mend.
The United Nations, as part of its effort to brand 2011 the International Year of Forests, released an assessment this week about forest extent, and quality, all around the world. First, the good news: Forest destruction is slowing down, according to assistant director general Eduardo Rojas-Briales of the UN’s Food and Agriculture Organization.
The 4.032 billion hectares (9.9 billion acres) of forests in the world in 2010 is down from an estimated 4.085 billion in 2000, said the FAO. But the speed at which which trees are being cut down is slowing from 8.3 million hectares a year in 1990-2000 to 5.2 million in the past decade. “There are evident signs that we could arrive at a balance in a few years,” said Rojas-Briales, adding that the deforestation rate was 50 million hectares a year 30 years ago. [AFP]
Asian countries have achieved particularly impressive results, with many adding to their total of forested territory.
“China has increased its forest by three million hectares (30,000 sq km) per year – no country has ever done anything like this before, it’s an enormous contribution,” said … Rojas-Briales. “But we can also highlight the case of Vietnam, a small and densely populated country that’s implemented very smart and comprehensive forest reform – or India, which has not controlled its population as China has and where standards of living are even lower. Nevertheless India has achieved a modest growth of its forest area.” [BBC News]
But the world is not out of the woods, so to speak, in bringing back the forest health of old.
Sunday marked the opening of the worldwide tiger summit, which brought together high-level representatives from the 13 tiger-habitat countries, including Russia and China, to discuss the best plan to save the tigers. The meeting goes through Wednesday.
Only about 3,200 tigers remain in the wild, and without help experts say populations will start to go extinct in less than 20 years.
“Here’s a species that’s literally on the brink of extinction,” said Jim Leape, director general of conservation group WWF. “This is the first time that world leaders have come together to focus on saving a single species, and this is a unique opportunity to mobilise the political will that’s required in saving the tiger.” [BBC News]
The working plan includes provisions to decrease poaching and smuggling of the tigers and calls for more protected habitats. Researchers say that if tigers are left alone and provided with enough habitat and prey, the population could double in 12 years.
Of all the tigers left in the world—and there aren’t many—70 percent of them are clustered into lands that make up just 6 percent of the total tiger habitat in the world. Save these spots, scientists say today, and you save the tigers.
In the journal PLoS Biology, a large group of researchers outline why their 6 percent solution could succeed where other conservation attempts have failed. Basically, they say, efforts to save the cat have been ambitious, but too broad. Job one has to be the protection of these 42 small “source sites” in Asia (seen on the map in the slideshow above), that are home to the core population of tigers.
“The long-term goal is to conserve an Asia-wide network of large landscapes where tigers can flourish,” said Nigel Leader-Williams from Cambridge University, one of the scientists on this study. “The immediate priority, however, must be to ensure that the few breeding populations still in existence can be protected and monitored. Without this, all other efforts are bound to fail.” [BBC News]
America seems to be more and more linked to Asia–not just by complicated financial ties, but also by currents of air pollution that are boosting smog levels in American skies. For years scientists wondered why some rural areas in the western United States had high levels of ozone, when the areas had very little industry or automobile traffic. The answer, apparently, was blowing in the wind.
A new study, published in Nature reveals that springtime ozone levels in western North America are on the rise, because of air pollution coming in from south and east Asia.