Bumblebees have the ability to determine pollen quality by sight.

New research suggests they do this by looking at flower features, such as petal color, and land only when they detect pollen of the highest quality, the University of Exeter reported.

The recent study, published today in the Journal of Experimental Biology, suggests pollen foraging in bees involves learned behaviors and individual decision-making. The ability allows the insects to quickly determine which pollen will be most nourishing for their valuable young.

 "There is still very little known about how bees decide which flowers to visit for pollen collection. Easily learning floral features based on pollen rewards, without needing any nectar rewards, is a fast and effective way to [recognize] those flower species which bees have previously experienced to be the best ones," Dr Natalie Hempel de Ibarra, Senior Lecturer in Neuroethology at the University of Exeter, said: 

The team made their findings by manipulating the quality of pollen offered to bees as well as diluting samples. They tested if the bees could determine the quality of the pollen before they landed on it if they could only see and smell it. They showed the bees four differently colored discs each containing stronger and less diluted pollens. They recorded the bees preferences and how those preferences changes as time went on.

"Bees need to be able to select flowers providing the most nutritious food for rearing their young. Since bumblebees don't eat pollen when foraging, it was unclear if or how they might be able to assess differences in quality. Here we've shown that they are able to detect differences in pollen, even before landing, which means they may be able to tell, just from the [color] of the petals, which flowers are worth visiting,"   said Doctor Elizabeth Nicholls, a former PhD student at The University of Exeter and now a Post Doctoral Research Fellow at the University of Sussex.