These woody wonders standing sentinel along sidewalks and in city parks do more to improve our lives than most of us realize. Just being near them has been shown to improve our health: One study found that people who live on tree-dense blocks are less likely to suffer from hypertension, obesity and diabetes than those who don't. We've all taken refuge in the shade of a leafy canopy on a hot day, but trees keep us cool in another way as well. When they photosynthesize they open tiny pores on their leaves called stomata that allow for gas exchange with the atmosphere. An open stoma also enables water inside the leaf to evaporate, which in turn causes the air around the leaf to cool.
When the first few sycamores began dying in UC Irvine's Aldrich Park in late 2014, the victims numbered in the dozens. But over the next several months, hundreds of cottonwoods, native willows, goldenrain and coral trees met the same fate. "We've seen infestations of pests, but nothing to this extent," said Richard Demerjian, director of UCI's Office of Environmental Planning and Sustainability. "It came as quite a shock." It was the work of the polyphagous shot hole borer, an invasive beetle that's been attacking and killing an astonishing range of trees throughout Southern California.
Retailers appear to be selling fewer ornamental plants laced with pesticides linked to bee population declines, according to a new report. Less than a quarter of the trees and flowers from stores and nurseries tested by environmental activists contained pesticides at levels that could be harmful to bees, which are vital to pollinating many of the nation's food crops. Two previous reports, in 2013 and 2014, revealed that more than half of the samples contained potentially dangerous levels of chemicals linked to bee deaths. "Our data indicates that compared to two years ago, fewer nurseries and garden stores are selling plants pre-treated with systemic neonicotinoid insecticides," said Susan Kegley, a chemist at the Pesticide Research Institute and lead author of the report released Tuesday by the institute and Friends of the Earth. Neonicotinoids, which mimic nicotine insecticides produced naturally in leafy plants, have been linked to the decline of bee populations.
Nasa has announced that it has found evidence of flowing water on Mars. Scientists have long speculated that Recurring Slope Lineae -- or dark patches -- on Mars were made up of briny water but the new findings prove that those patches are caused by liquid water, which it has established by finding hydrated salts. Several hundred camped outside the London store in Covent Garden. The 6s will have new features like a vastly improved camera and a pressure-sensitive "3D Touch" display
Flowers might form their memories because of the protein that causes mad cow disease, according to a new study. Plants have long been observed to have something like memory, remembering information like when is the best time to flower and passing that information on to their offspring. They have even been known to become "forgetful" – wiping out memories of past traumas if they are causing problems. But a new study shows that prion proteins, which are responsible for degenerative illnesses in humans animals, can be used by plants to store memory. The same prions that cause human brains to suffer such horrible problems with mad cow disease, for instance, may help plants store things as memory and so allow them to make the most of their environment.