Transgenerational epigenetic effects of intra-sexual competition on the genital size of the brown stink bug (Euschistus heros)

• Grant number: 24/17484-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2025
• End date: May 31, 2026
• Field of knowledge: Biological Sciences - Zoology
• Principal Investigator: Bruno Celso Feltrin Genevcius
• Grantee: Daniel Batista
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 23/14170-7 - Unraveling genetic, ecological, and epigenetic factors in the development and evolution of complex reproductive structures in insects, AP.R

Abstract

Epigenetic mechanisms are fundamental for regulating animal development and adaptation. These mechanisms are thought to have a significant influence on the phenotypic plasticity of various structures and behaviors across different taxa. In the brown soybean stink bug, Euschistus heros, prolonged copulation is one of the strategies for reproductive success when an individual is exposed to a scenario of sexual competition for mates. This prolongation is linked to the shape and size of male reproductive structures, as individuals exhibit larger genitalia when the density of male competitors is higher. This plastic response provides a significant competitive advantage to males. However, it is possible that this trait is passed on to offspring through epigenetic inheritance. This project aims to test the hypothesis that morphological changes in the genitalia of bugs in response to intrasexual competition can be transmitted to offspring via epigenetic factors. We will conduct laboratory experiments manipulating the sex ratio in the development environment of the bugs, simulating scenarios of presence and absence of competition. Then, we will test whether the offspring of individuals subjected to competition will exhibit larger genitalia.