Caterpillar diet breadth in Área de Conservación Guanacaste, a large and diverse Neotropical wildland in northwestern Costa Rica: toxins, silica, aluminum, and sclerophylly

A comprehensive analysis of caterpillar–food plant interactions over nearly four decades in the Área de Conservación Guanacaste (ACG), Costa Rica, reveals that dietary specialization is strongly influenced by plant defenses. The study, based on 431,212 rearing records spanning 7,160 Lepidoptera and 2,489 plant species, found that unpalatable, aposematic herbivores tend to be specialists while highly toxic plant families, such as Aristolochiaceae and Zamiaceae, host many monophagous caterpillars. Biochemical and structural defenses in plants appear to mediate herbivore diet breadth, with defended plant families hosting fewer polyphagous species compared to less-defended ones. The research also highlights that while plant species composition remained relatively stable, caterpillar communities showed significant changes over time, particularly in rainforest and dry forest habitats.

Quicke, D. L. J., Brown, A., Hajibabaei, M., Manjunath, R., Naik, S., Ratnasingham, S., Sones, J., Jacques, B. St., Smith, M. A., Zamora, N., Brown, J. W., Matson, T. A., Miller, S. E., Burns, J. M., Goldstein, P. Z., Metz, M. A., Robbins, R., Solis, M. A., Chacon, I., et al. (2025). Caterpillar diet breadth in Área de Conservación Guanacaste, a large and diverse Neotropical wildland in northwestern Costa Rica: toxins, silica, aluminum, and sclerophylly. Frontiers in Ecology and Evolution, 13. https://doi.org/10.3389/fevo.2025.1647436