Ecology dictates the value of memory for foraging bees

Area of Science:

• Animal behavior
• Cognitive ecology
• Evolutionary biology

Background:

• Ecological intelligence hypotheses link animal learning and memory to foraging demands.
• Understanding cognitive evolution requires identifying environments where cognitive investment is most beneficial.
• Seasonal variation in forage availability presents a natural experiment to study cognitive benefits.

Purpose of the Study:

• To investigate how the benefits of short-term memory vary with resource availability in the social insect Bombus terrestris audax.
• To determine if cognitive performance predicts foraging efficiency under different environmental conditions.
• To explore the role of both resource-rich and resource-scarce environments in driving cognitive evolution.

Main Methods:

• Utilized a radial arm maze (RAM) to assay short-term memory in Bombus terrestris audax.
• Employed a staggered design over two years, testing bees before wild foraging.
• Monitored seasonal variation in forage availability (spring abundance vs. summer dearth).

Main Results:

• Radial arm maze performance predicted foraging efficiency in plentiful spring conditions.
• This relationship between cognitive performance and foraging efficiency reversed during the summer floral dearth.
• Colony fitness was linked to foraging efficiency, highlighting the adaptive value of cognitive traits.

Conclusions:

• The evolution of cognitive traits is not solely driven by harsh environments with scarce resources.
• Challenging environments with multiple, rapidly presented options may also be significant drivers of cognitive evolution.
• Seasonal dynamics in forage availability critically influence the adaptive benefits of cognitive abilities in social insects.