Bumblebees use their sense of smell to locate their nest when visual information is conflicting, As detailed in a study published in Frontiers in Behavioral Neuroscience. Researchers found that bumblebees rely on their own scent marks, which they deposit at their nest entrance while leaving for a foraging trip, to find their way back when visual cues are not reliable. Bumblebees have a pair of compound eyes that can distinguish UV and most colours, as well as three simple eyes that detect polarised light. Their sense of smell is approximately 100 times more sensitive than humans and can detect illegal drugs, explosives, pregnancy, and early-stage cancers and diabetes.
As detailed in a recent study published in Frontiers in Behavioral Neuroscience, bumblebees use their sense of smell to locate their nest when visual information is conflicting. The researchers found that bumblebees rely on their own scent marks, which they deposit at their nest entrance while leaving for a foraging trip, to find their way back home when visual cues are not sufficiently reliable.
Bumblebees have an excellent vision, with a pair of compound eyes that can distinguish UV and most colours except red, as well as three additional simple eyes that specialise in detecting polarised light. However, their sense of smell is approximately 100 times more sensitive than humans, making it a crucial tool for navigation.
The study was conducted by researchers from Bielefeld University in Germany, who studied the homing behaviour of the buff-tailed bumblebee Bombus terrestris in a laboratory setting. In nature, these bumblebees nest in abandoned mouseholes, hidden under grass or leaves. In the laboratory, the foragers learned to locate their nest entrance by visually orienting themselves against two sets of landmarks within a round enclosed flight arena.
The first set of landmarks consisted of three black vertical stripes, each 12cm wide and 85cm long, against the white background of the arena walls. The second set of landmarks consisted of three cylinders, each 2.5cm wide and 15cm high, arranged in a triangle around the entrance hole. After some practice, the workers were able to fly straight back to the entrance when returning, using the visual landmarks to guide them.
However, when the visual cues were not sufficiently reliable, such as when familiar landmarks were blown away by the wind, the bumblebees were able to rely on their sense of smell to find their way back home. The researchers found that the bumblebees were able to use their own scent marks, which they deposited at their nest entrance while leaving for a foraging trip, to locate their nest even in the absence of visual cues.
The study highlights the importance of scent in bumblebee navigation and suggests that bumblebees may be able to adapt to changing landscapes by relying on their sense of smell when visual cues are not available. The researchers note that the study has implications for understanding the behaviour of other insects and animals that use scent for navigation, such as ants and dogs.
Last but not least, the study shows that bumblebees are able to use their sense of smell to locate their nest when visual information is conflicting. The researchers found that bumblebees rely on their own scent marks to find their way back home when visual cues are not sufficiently reliable. The study highlights the importance of scent in bumblebee navigation and suggests that bumblebees may be able to adapt to changing landscapes by relying on their sense of smell when visual cues are not available.
