SEX-MEDIATED SPATIAL SEGREGATION AND HERBIVORY IN Cecropia pachystachya, A NEWCOMER TO THE XERIC CAMPO RUPESTRE

Sexual segregation and herbivory in Cecropia pachystachya

Abstract

The spatial distribution and ecological interactions of Cecropia pachystachya, a newcomer and invasive species in the xeric campo rupestre were investigated. This species is dioecious and a frequent colonizer widely distributed in the Atlantic rainforest domain in southeastern Brazil. The aim of this study was to explore the ecological dynamics of this newly established species in an arid environment characterized by rich biodiversity and high environmental stress. The results showed that female individuals were predominantly located closer to watercourses. Herbivory rates were significantly higher in male plants, while females showed stronger physical defenses, which included thicker leaves and a higher density of trichomes. These findings highlight the complex interaction between resource availability, herbivory, and sex-based traits that influence the distribution and survival strategies of dioecious plants. The study also highlights the possible ecological impacts of the expansion of C. pachystachya in the Campo Rupestre, a fragile ecosystem rich in biodiversity that is under high pressure caused by human and climate disturbances. Understanding how this species interacts with its new environment is fundamental for predicting its long-term ecological dynamics and for devising strategies to mitigate biological invasion.