Flight Dispersal in Supratidal Rockpool Beetles.

Area of Science:

• Ecology
• Evolutionary Biology
• Entomology

Background:

• Supratidal rockpool insects face challenges in temporary, fragmented habitats.
• Flight dispersal is crucial for insect survival, influencing colonization, gene flow, and evolution.

Purpose of the Study:

• To compare the flight dispersal capacity of two congeneric beetle species, *Ochthebius quadricollis* and *Ochthebius lejolisii*.
• To investigate the ecological and evolutionary implications of dispersal in these extreme environments.

Main Methods:

• Experimental flight assays were conducted under controlled conditions.
• Wing morphology, including size and shape, was analyzed.
• Microsatellite markers were used to assess genetic differentiation between populations.

Main Results:

• Both species demonstrated significant flight activity (60-80% of individuals).
• Females of *O. quadricollis* showed larger body size, wing area, and lower wing loading, suggesting female-biased dispersal.
• Wing shape indicated high short-distance flight capacity, while molecular data revealed low genetic divergence and no isolation by distance.

Conclusions:

• The findings suggest similar flight behaviors and potential for passive, wind-assisted dispersal in both species.
• Morphological differences in females may facilitate greater dispersal.
• Low genetic differentiation implies ongoing gene flow between populations.