MODE OF SWARMING IN RELATION TO REPRODUCTIVE ISOLATION IN MAYFLIES

Area of Science:

• Ecology
• Evolutionary Biology
• Entomology

Background:

• Mayfly males engage in swarming behavior, congregating around specific objects (swarm markers) to attract females.
• Leptophlebia marginata populations exhibit varied orientation preferences for swarm markers, including trees and horizontal ground objects.

Purpose of the Study:

• To investigate the different swarming behaviors in Leptophlebi marginata populations.
• To determine the evolutionary origins and ecological drivers of distinct swarming patterns.

Main Methods:

• Field observations of Leptophlebia marginata swarming behavior in central Finland.
• Analysis of genetic and morphological data from sympatric populations with different swarming types.

Main Results:

• Leptophlebia marginata were observed to orient to both trees and horizontal pale objects.
• Populations showed distinct genetic and morphological differences, with some gene flow between swarming types.
• Tree-swarming appears to be the ancestral state, while horizontal swarming is a derived trait, favored by wind rather than predation.

Conclusions:

• Swarming behavior in mayflies, particularly Leptophlebia marginata, serves as a crucial mechanism for premating isolation.
• The evolution of different swarming strategies, like ground-level orientation, can be influenced by environmental factors such as wind.