From Science Daily:

http://www.sciencedaily.com/releases/2008/07/080715204730.htm

Bees were divided into a control group and a group that were injected 
with lipopolysaccharide, a substance that stimulated an immune 
response without a need for the bee to be infected with a disease. 
Bees were offered the choice of blue and yellow artificial flowers 
only one type of which contained sugar water. An individual's flight 
was recorded over ninety visits to these flowers. Eventually the bees 
spent almost all of their time going to the rewarding flowers, but it 
took the immune stimulated bees longer to reach this point.

Dr Mallon added: "This work has two important applications. Firstly, 
there is a lot of interest in the connections between the immune 
system and the nervous system in human biology. The Mallon lab was the 
first to show that these interactions also exist in the much more 
experimentally tractable insects.

"Secondly, there is concern about both the decline in wild bumble-bee 
species and the effects of disease on the honeybee industry. It has 
been shown that learning is vitally important to how well a colony 
prospers. This effect of immunity on learning highlights a previously 
unconsidered effect of disease on colony success."

Bill Truesdell
Bath, Maine

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