In my previous post I shared research that suggests bumblebees are attracted to “bee-ness,” or features associated with other bumblebees.
Do bumblebees have preferences for certain colours and patterns?
It would make sense that bumblebees would be attracted to particular features of the environment because somehow, amongst all the objects out there in the world, they have to find food (flower nectar and pollen). So they are faced with the question, “What should I land on?”
I remember in our bee lab one of our PhD students (I’ll call her G) noticed a bee landed on a colourful packet of seeds. She also noticed bees landing on things such as blue and white soccer balls, floral patterned clothes…what exactly was attracting the bees to those things?
One day, to see what the bees would do, G placed a photo of a blue flower in our flight cage. (The flight cage was a large, screened, gazebo-type structure in which we let the bumblebees fly during our experiments.) A bumblebee landed on the photo and actually extended its proboscis (tongue), as if it expected food!
And from there, a PhD thesis was born.
First, G wondered whether bumblebees prefer some colours over others. She gave bumblebees the choice between white, red, blue, and yellow discs. A “choice” was counted if a bumblebee flew close to, or landed on, a disc. She gave each bee 20 choices. As shown in the pie graph below, bumblebees preferred yellow and blue discs over white and red discs.
The important thing to note is that the bumblebees were not rewarded for approaching or landing on any of the discs. That is, they did not receive any food for any of their choices. So the preference for yellow and blue over white and red was not learned.
(Another important thing to note is that we interpret these colours using human eyes. Yellow and blue look different to bees because they have a different visual system. For instance, bees can see UV rays whereas we can’t. But for simplicity, we’ll just refer to the colours by their human name.)
Next, G wondered whether bumblebees prefer certain patterns over others. She gave the bees a choice between three simple patterns: yellow and blue concentric circles, a yellow and blue radial pattern, and a plain blue disc. As seen below, bees substantially preferred the radial pattern over the others.
So bumblebees DO appear to have preferences for certain colours and patterns! In these instances they prefer yellow and blue, and they like radial patterns.
Pretty good for a creature with a brain the size of a grass seed.
To read more about G’s research, click here.