The real-life mystery that inspired Alfred Hitchcock's 1963 thriller The Birds has been solved, researchers say. Hitchcock is said to have largely based the film on a bizarre incident in 1961, when flocks of crazed seabirds slammed into homes in California's Monterey Bay. Researchers now believe that, rather than being intent on destroying humanity, the birds were poisoned, USA Today reports.
Oceanographers examining the contents of seabirds and turtles gathered in the area in 1961 found that most of them had consumed plankton that contained large quantities of a nerve-damaging toxin, which can cause confusion and seizures in birds. They believe the toxin reached the ocean from faulty septic tanks installed during California's housing boom in the '60s. The lead researcher says she has been fascinated with Hitchcock's movie ever since it terrified her when she was very young. "When I started work on harmful algae blooms and their toxins, and then learned of this super-exciting connection, I felt I had to work on this," she says. (More Alfred Hitchcock stories.)