October 3, 2013 |
It's been a point of heated debate among scientists for years: Just when in Earth's history did flowering plants first appear? In a paper published recently in the journal Frontiers in Plant Science , researchers say they have discovered fossilized pollen grains that date back 243 million years -- more than 100 million years earlier than previously thought. If true, that would suggest that flowering plants, or angiosperms, appeared at roughly the same time as dinosaurs, in the Middle Triassic period.
August 15, 2013 |
Archaeologists have debated for decades over what caused the once-flourishing civilizations along the eastern Mediterranean coast to collapse about 1200 BC. Many scholars have cited warfare, political unrest and natural disaster as factors. But a new study supports the theory that climate change was largely responsible. Analyzing ancient pollen grains from Cyprus, researchers concluded that a massive drought hit the region about 3,200 years ago . Ancient writings have described crop failures, famines and invasions about the same time, suggesting that the drying trend triggered a chain of events that led to widespread societal collapse of these Late Bronze Age civilizations.
August 13, 2013 |
Unlike many plants considered invasive, fennel does everything it can to ingratiate itself into the garden. Its leaves are attractive -- feathery and delicate -- and the umbrella-shaped blooms of bright yellow flowers that come in summer serve as miniature landing pads for pollinators. Every part of fennel, root to leaf to pollen to fruit, is infused with the varying levels of its iconic licorice flavor. Unlike other aromatic crops -- dill, cumin, anise, caraway -- only fennel ( Foeniculum vulgare )
July 24, 2013 |
Pesticides sprayed on crops could be making honey bees susceptible to a fatal parasite and contributing to recent declines in bee populations, according to a study. Researchers found 35 pesticides, some at lethal levels, in the pollen collected from bees servicing major food crops in five states, including California, according to the study published online Wednesday in the journal PLOS One. Levels for two chemicals were above the dose that would kill half a population within two days, according to the report.
April 29, 2013 |
Honeybees that live off the same sweetener found in soft drinks could be more vulnerable to the microbial enemies and pesticides believed to be linked to catastrophic collapse of honeybee colonies worldwide, a new study suggests. Researchers identified a compound found in the wall of plant pollen that appears to activate the genes that help metabolize toxins, including pesticides, according to the study published Monday in the Proceedings of the National Academies of Science. Although pollen winds up in the honey produced by Apis mellifera , these bees used to pollinate crops spend more time sipping on the same sugar substitute that is ubiquitous in processed foods - high-fructose corn syrup.
March 19, 2013 |
Gesundheit! If it seems to you allergy sufferers that you're reaching for Kleenex and hay fever pills earlier and earlier each spring to ward off sneezing fits, you may be right. A panel of climate scientists and plant physiologists said Tuesday that higher temperatures and carbon dioxide levels are linked to longer and more intense pollen production. "What we're seeing with additional warming and earlier springs is that the trees are flowering earlier and producing more pollen," said Lewis Ziska, a research plant physiologist with the U.S. Department of Agriculture.