Within a few years, cockroaches have evolved to avoid sugar. Remarkably, their adaptation is a result of sugar-laced traps. Unlike humans, they don't have to use willpower. Instead, cockroaches have a built-in aversion based on taste: sugary flavor comes across as bitter.
Cockroaches in a recent studied were sampled from colonies in the U.S, Puerto Rico, South Korea and Russia. Among the 19 populations examined, seven included cockroaches with the sugar-aversive behavior.
Researcher Coby Schal of North Carolina State University
noted that the evolution came about "incredibly fast" but also pointed out that some bacteria evolve even more quickly.
In a simple experimental design, researchers filmed cockroaches to understand their behavior. The study videotaped groups of cockroaches as they chose between two food sources. The bugs were given a choice of a glucose or fructose based jelly, and later, peanut butter or jelly, and observed as they made their choice.
The phenomenon of glucose aversion has been for known some time in the extermination industry, and profession pest-control companies have switched to new types of bait, either high carbohydrate or high protein.
This latest research demonstrates just how well cockroaches learn, and how exceptionally adaptable they are to a variety of challenges.