Katarina Piponi

2024 PhD Studentship
The evolution of same-sex sexual behaviour
Disentangling the ‘Darwinian paradox’ of homosexual behaviour in primates
Imperial College London


Same-sex sexual behaviour (SSB) has been observed in a diverse array of species spanning the Tree of Life. The occurrence of SSB poses a ‘Darwinian paradox’ due to lacking a direct contribution to reproductive success. As a result, previous theories aiming to address reasons for SSB occurrence have focused on the seeming ‘paradox’ of its existence. These theories assume negative fitness consequence for spending time engaging in same-sex sexual behaviour as opposed to mating that may result in offspring.

There is a lack of studies that systematically focus on same-sex sexual behaviour in animals. Together with colleagues from the research group led by Prof. Vincent Savolainen at Imperial College London, we aim to use an interdisciplinary approach to unravel the function and evolutionary foundations of SSB by integrating behavioural and genomic techniques. Our findings have broad implications, bridging gaps in understanding this behaviour’s prevalence in nature.

Pictured are two rhesus macaques – an adolescent and young adult photographed in Longleat Safari Park during a preliminary study. Photo: Katarina Piponi
New scientific evidence

We investigate same-sex sexual behaviour by collecting high-quality and extensive data from a semi-free roaming population of rhesus macaques on a small island off the coast of Puerto Rico. We look at the social contexts in which same-sex sexual behaviour occurs, while using genetic and genomic analysis to begin to unravel its biological basis.

Our research is interdisciplinary at its core, we use both behavioural observation and genetic and genomic analysis. We hope for our investigation to bring further clarity to an aspect of behaviour whose causes and function are still unclear.

Our findings have broad implications, bridging gaps in understanding this behaviour’s prevalence in nature. For both academic and non-academic audiences, this research offers a fresh perspective on the natural diversity of sexual behaviour, fostering a more inclusive and informed discourse.

Tackling big evolutionary questions

Research, particularly in the realms of behaviour, genetics, and human evolution, has always been the trajectory I wanted to pursue. After two years in the biotech industry, my aim was to re-enter the academic circle, concentrating on a field I wish to specialise in.

The EET Scholarship allows me to delve into these evolutionary puzzles, employing a comprehensive approach: behavioural data collection in Puerto Rico, molecular insights through DNA analysis, and predictive research with bioinformatics. I firmly believe that as technology progresses, there is a responsibility to ensure the accurate dissemination of information.

Leveraging evolutionary insights to address societal challenges is a crucial pursuit, particularly relevant in our modern society.