Evolvability and Evolutionary Constrains of Sexual Dimorphism in Simiiform Primates

• Grant number: 25/08113-6
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Biological Sciences - Genetics - Quantitative Genetics
• Principal Investigator: Gabriel Henrique Marroig Zambonato
• Grantee: Lucas Arantes Camacho
• Supervisor: Thomas Fredrik Hansen
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Oslo (UiO), Norway
• Associated to the scholarship: 22/08168-7 - Modularity and morphological diversification and its relation to diet and mating systems in old world monkeys (Primates, Catarrhini), BP.DR

Abstract

Variation is the foundation of evolution by natural selection, as it enables differential survival and, when heritable, allows evolutionary change. Phenotypic variation (P) is the sum, and eventually interaction of genetic (G) and environmental (E) effects. Studying G provides insight into the genetic underlying of traits and how genetic correlations, driven by shared function or development, can influence phenotypic evolution. These correlations, or trait integration, can constrain or facilitate evolution depending on their alignment with the adaptive peak. The amount of available genetic variation in any given direction is a critical measure of a population's ability to evolve, a property known as evolvability. Evolvability is thus a central concept in evolutionary quantitative genetics and plays a key role in determining the evolutionary response to selection. This project focuses on how integration affect evolvability in the context of sexual dimorphism among primates. These primates display a wide range of dimorphism, from minimal differences in gibbons to extreme male-biased size differences in mandrills and geladas. Many factors have been proposed to explain these patterns, including sexual selection, diet, body size, and phylogeny. However, the role of evolvability and trait integration in shaping sexual dimorphism has received little attention. By examining how phenotypic integration reflects both the amount and the directional biases of available variation, this research aims to assess whether variation itself influences the evolution of sexual dimorphism. This perspective may offer new insights into why dimorphism varies so greatly across simiiform species. (AU)