We think of Bumblebees as daylight flyers that rely on visual cues to find food and return to the nest. Howesver, when pitched in total darkness, bumblebees can still find their way. This is adaptive as many bumblebees nest in mouse holes with tortuous (and dark!) underground galleries. When bumblebees were placed in complete darkness, they were able to navigate to a sugar solution 40 cm distant and back to their nest.* The navigation to the food was not direct and neither was the return trip. Over time, bumblebees were able to navigate to the food and back in less time.
How do they navigate? Bumblebees use chemical secretions to mark trails within their nest and this marking behavior extends to foraging outside the nest on foot. Rotating the surface relative to the nest entrance sends bumblebees in the wrong direction, indicating that they used odor marks to find their way. Bumblebees still traveled in the correct compass direction if odors were removed from the surface indicating that magnetic cues may also be used. Bumblebees do not lay and reinforce odor trails that result in linear travel of workers from the food to the nest as is done by ants. The bumblebees are less direct and less good at ground based foraging than ants but have evolved the capacity for ground based as well as aerial navigation.
*L. Chittka, N. M. Williams, H. Rasmussen and J. D. Thomson. ￼Navigation without vision: bumblebee orientation in complete darkness. Proc. R. Soc. Lond. B (1999) 266, 45-50.