A new study suggests that crows can recognize symbols that represent quantities of items. At Japan's Utsunomiya University, crows were shown two containers. Only the container marked with five symbols contained the food. The researchers trained the crows to identify the food container 70% of the time. Alfred Hitchcock could not be reached for comment. From Mainichi Daily News:
The crows later received tests for non-numerical clues such as element configuration, shape, total filled area and novel sets of quantity involving choices with figures ranging from two to eight.
The eight crows had a 70 to 90 percent success rate choosing the container holding food for 19 of the 20 choices with which they were presented.
(Shoei) Sugita and other researchers have also discovered that crows can distinguish between men's and women's faces, with the research results made public last year. "We want to reveal more about the unknown intelligence of crows," the professor said.