Plant evolution can mediate negative effects from honey bees on wild pollinators

Area of Science:

• Ecology
• Evolutionary Biology
• Agroecosystems

Background:

• Managed pollinators, like honey bees, are introduced to agroecosystems for pollination services.
• The impact of managed pollinators on evolutionary dynamics between plants and wild pollinators is poorly understood.
• Understanding these interactions is crucial for maintaining biodiversity and ecosystem services.

Purpose of the Study:

• To develop a model assessing the effects of managed honey bees on plant-wild pollinator mutualisms.
• To investigate how competition and plant evolution influence pollinator displacement and coexistence.
• To determine the role of plant traits in mediating interactions between managed and wild pollinators.

Main Methods:

• Developed a mathematical model to simulate interactions between honey bees, wild pollinators, and plants.
• Tracked the population dynamics of both pollinators and plants under varying competitive advantages and carrying capacities.
• Analyzed the evolutionary responses of plants, specifically changes in floral traits attractive to different pollinators.

Main Results:

• Honey bees with competitive advantages or higher carrying capacities displaced wild pollinators.
• Displacement led to reduced plant density due to lower pollination efficiency by honey bees compared to coevolved wild pollinators.
• Plants evolved traits favoring honey bees, further promoting wild pollinator displacement, though increased investment costs could promote coexistence.

Conclusions:

• Plant evolution can drive the displacement of wild pollinators by managed honey bees.
• Limited plant evolution may facilitate pollinator coexistence, highlighting the importance of evolutionary capacity.
• The impact of honey bees on wild pollinators and ecosystem services in agroecosystems is contingent on plant population evolution.