Changes in the trait outcomes of tropical plants under severe defaunation.

• Grant number: 23/18342-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2024
• End date: February 28, 2026
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Mauro Galetti Rodrigues
• Grantee: Rafaela Mainardi Forti da Silva
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated research grant: 21/10639-5 - Center for Research on Biodiversity Dynamics and Climate Change, AP.CEPID

Abstract

All plants are susceptible to herbivory, and they evolved defenses to avoid being eaten. Plants created ecological links with animals that, if to break due to modification or extinction of connection, cause a cascade effect. One of the current loss of links is the defaunation of large herbivores that can alter the ecosystem diversity and services, similar to what occurs in islands that lack herbivores. Therefore, there is a need to understand how future forests will be affected by defaunation so that mitigating actions, such as reforestation and rewilding, can be applied. Seedlings are the first phase where these effects can be observed, and modifications in their properties, such as the functional traits, will affect the composition and structure of forests. To assess the effect of defaunation on the dichotomy between growth, defense, and photosynthetic potential on seedlings, we selected four areas in the Atlantic Forest and will measure morphological traits, such as the leaf dry matter content, leaf density, leaf thickness, height, leaf area, specific leaf area, and chlorophyll content. So, variations in these traits can show the behavior of plants in the absence of herbivores and a possible adaptation to the new scenario. In this proposal, we intend to combine a theoretical and field-based experiment to understand at the community level the effects of the loss of large mammalian herbivores on seedling traits in tropical forests, being that we expect to find a relaxation of investment in traits against herbivory occurs (smaller defense traits), leading to greater competition among seedlings to obtain resources (higher leaf content of chlorophyll) and develop (higher height, leaf area, and specific leaf area).