No Preference for Performance: Host Plant Preference, Offspring Performance and Host Plant Distribution in the...

Area of Science:

• Ecology
• Evolutionary Biology
• Entomology

Background:

• The preference-performance hypothesis suggests female insects should select host plants optimizing offspring development.
• Understanding insect-plant coevolution requires examining factors influencing female oviposition site selection.

Purpose of the Study:

• To test the preference-performance hypothesis in the northern brown argus butterfly (Aricia artaxerxes).
• To investigate the relationship between female host plant preference, larval performance, and host plant distribution in Sweden.

Main Methods:

• Comparing Aricia artaxerxes female oviposition preference between Geranium sylvaticum and Geranium sanguineum.
• Assessing larval growth rates on both host plant species.
• Correlating host plant preference with the geographic distribution of butterflies and host plants.

Main Results:

• A. artaxerxes females preferred Geranium sylvaticum, despite slightly reduced larval growth compared to Geranium sanguineum.
• Geranium sylvaticum is more abundant and likely more utilized by A. artaxerxes in the study region.
• Female preference did not align with optimal offspring performance, indicating other factors are involved.

Conclusions:

• Female host plant preference in A. artaxerxes is not solely driven by offspring performance.
• Host plant abundance and geographic distribution significantly influence oviposition choices.
• This challenges the strict interpretation of the preference-performance hypothesis in insect-plant interactions.