Bumblebees use and repair artificial honeypots

Insects have long been known to show flexibility when building structures, including the ability to modify and repair them, and incorporate novel materials¹. Even honeybee (Apis mellifera) nest cells, known for their highly stereotyped hexagonal geometry, can diverge from this shape² and be altered by workers³. Compared to those of honeybees, bumblebee (Bombus spp.) nests have been described as "seemingly haphazard"¹; found in a variety of cavity types¹, they show variation in the size and location of honeypots and other objects built to rear brood of various sizes (Figure 1A). This natural variability points to potential flexibility in bumblebees' use and repair of constructed objects. To examine this possibility, we asked whether bumblebees (Bombus impatiens) would use artificial 3D-printed honeypots and complete three partial structures to create functional honeypots. Bees readily used the complete artificial honeypots and completed the partial honeypots to produce a variety of resulting structures. Individuals alternated building the same honeypot, worked on multiple honeypots concurrently, and dismantled and reallocated materials to complete or reshape honeypots. These observations indicate that bumblebees can flexibly respond to different scenarios when building.