What maintains the floral polymorphism in Epidendrum fulgens (Orchidaceae)?

• Grant number: 21/10798-6
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): December 01, 2022
• Effective date (End): February 29, 2024
• Field of knowledge: Biological Sciences - Botany
• Principal Investigator: Fábio Pinheiro
• Grantee: Beatriz Lucas Arida
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

One of the most diverse attributes in nature is the color of flowers, and understanding the mechanisms that create and maintain this variation is critical to understanding Earth's diversity. The Orchidaceae family is known to have a large morphological variation of flowers, and also a high index of species with pollinator deception strategies, and many studies report this variation as being of primary importance for attracting pollinators in deceptive species. Floral polymorphism in deceptive species can be maintained through a fluctuating selection mechanism, in which pollinator-mediated selection can act on distinct floral characters over time, so that this polymorphism is variable. This project seeks to understand whether the intraspecific variation of the floral coloration of Epidendrum fulgens Brongn. (Orchidaceae), a generalist species with a deception pollination strategy, increases the reproductive success of plants. The intensity and direction of natural selection over two consecutive years will be estimated, which attributes are or are not under pollinator-mediated selection, and also whether this selection is constant in different flowering periods. For this, controlled experiments will be carried out in the field, which are based on the exposure of individuals to floral visitors and on the monitoring of reproductive trates of individuals from a natural population. This project aims to help elucidate questions about the processes that act in the maintenance of floral polymorphism and how this variation influences natural selection within populations.