The search for the killer of America's bees is a little bit like an Agatha Christie novel. Suspicion has turned toward one shady character and then another: declining habitat; parasites; diseases; pesticides.
Or did they all conspire in the recent mass murder of the country's bees?
Today, two new studies are turning the spotlight of suspicion toward a specific class of insecticides called neonicotinoids. It's becoming increasingly clear that these chemicals are present — although at low levels — across huge parts of American farmland. And they may be addling the brains of our bees.