# Tongue microstructure physically constrains division of labor in bumblebee foraging

## TL;DR

This paper shows that the physical structure of bumblebee tongues explains why queens stop foraging when workers appear.

## Contribution

The study provides physical evidence linking tongue microstructure to the division of foraging labor in bumblebees.

## Key findings

- Bumblebee tongue microstructure affects foraging efficiency.
- Physical tongue traits explain caste-specific foraging behavior shifts.
- Queens' foraging decline is tied to their less efficient tongue structure.

## Abstract

Bumblebee (Bombus terrestris) is a primitively eusocial species that sustains its colonies by dividing foraging duties between queens and workers. Previous research emphasizes hormonal, metabolic, and behavioral contrasts between the castes but seldom considers why queens relinquish foraging once workers emerge. Here, we link foraging efficiency to tongue microstructure, providing physical evidence for the shift in bumblebee foraging behavior.