Two types of refuge have opposite effects on the size of larval aggregations in a tropical defoliator

  title={Two types of refuge have opposite effects on the size of larval aggregations in a tropical defoliator},
  author={Finbarr G. Horgan},
  journal={European Journal of Endocrinology},
  • F. Horgan
  • Published 3 May 2005
  • Biology
  • European Journal of Endocrinology
Many gregarious insects aggregate in naturally occurring refuges on their host plants. However, when refuges are filled, they may be forced to aggregate on exposed areas of the plant. This study examines the effects of refuge saturation on group size and defence against parasitism in larvae of Ammalo helops Cramer (Lepidoptera: Arctiidae) that form day-resting groups on the trunks of weeping laurel, Ficus benjamina L., in El Salvador. Population densities, group sizes and parasitism were… 

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