Bumble Bee Collective Acclimation

Linking individual physiology to colony-level responses to thermal stress.

Bumble bees are essential pollinators that face rising thermal stress as climates warm. We study how physiology and collective behavior interact to determine how bees respond to changing temperatures, from individual queens to entire colonies.

Discontinuous gas exchange patterns in bumble bees

Figure 1

Figure 1. Discontinuous gas exchange patterns in two bumble bee species measured at the same temperature. Both species show cyclic patterns of spiracle opening and closing, but differ in the amplitude and timing of breathing.

Thermal sensitivity of queen physiology

We study how temperature shapes the physiology of bumble bee queens during colony founding. In our work, queens exposed to warm temperatures showed little evidence of individual acclimation in metabolic rate, water loss rate, or thermal tolerance. At the same time, bee species differ in how they breathe, and certain species show greater thermal sensitivity of metabolic rate than others.

Metabolic rate: species differ in thermal sensitivity
Water loss: limited evidence for individual acclimation
Respiration: interspecific differences in physiological responses to heat

Goal

Understand how physiological differences among bee species shape their vulnerability to warming climates.

Bumble bee nest and coordinated behavior illustration

Section 2

Collective acclimation in whole colonies

Because individual queens show limited physiological acclimation, we are now asking whether entire colonies can acclimate collectively. Bumble bee nests function as integrated systems in which workers regulate the thermal environment through coordinated activity, movement, and nest-level behavior.

Nest responses: colonies exposed to warm and cool environments
Coordinated behavior: workers collectively regulate nest conditions
Superorganism physiology: colony-level buffering of thermal stress

Big question

Can bumble bee colonies acclimate as superorganisms, even when individual bees show limited physiological flexibility?