Many beekeepers feed their honey bees sucrose or high-fructose corn syrup when times are lean inside the hive. This practice has come under scrutiny, however, in response to colony collapse disorder, the massive — and as yet not fully explained — annual die-off of honey bees in the U.S. and Europe. Some suspect that inadequate nutrition plays a role in honey bee declines. Scientists took a broad look at changes in gene activity in response to diet in the Western honey bee, and found significant differences occur depending on what the bees eat.