Natasha Gillies

Ecology, evolution, and the mechanics of parental care

The evolution of biparental care requires males and females to overcome deep evolutionary conflicts in a feat achieved by only a fraction of life on Earth. My research explores how species transition away from evolutionary sexual conflict toward long-term monogamous systems where aligned reproductive interests maximise cooperation.

Currently a Leverhulme Early Career Fellow at the University of Sheffield, I use comparative phylogenetic approaches with targeted experimental work in burying beetles and seabirds to explore how mating systems interact with parental investment to drive the evolution of biparental care. By investigating these diverse taxa, my work aims to uncover the fundamental evolutionary and ecological conditions that allow stable, joint parental investment to emerge and stabilize in nature.

Alongside this, I maintain an interest in seabirds and the mechanisms they use to coordinate behaviour in dynamic environments. My previous work used high-resolution biologging to study movement ecology in polar seabirds, including wandering albatrosses, black-browed albatrosses, and black-legged kittiwakes, to explore intrinsic and extrinsic drivers of movement.

My PhD research focused on the coordination of biparental care in long-lived seabirds, investigating the mechanisms that allow parents to negotiate care under challenging and uncertain conditions. This work continues to inform my broader research programme on the evolution of parental care and cooperative behaviour.

Research

Leverhulme Early Career Fellow, University of Sheffield

February 2026 - present

From beetles to birds: cooperation versus conflict in biparental care

My fellowship research investigates the importance of true mutual benefit in shaping the evolution of biparental care, and whether conflict-driven approaches may limit our understanding of this behaviour. I focus on the concept of partner value - the idea that an individual’s fitness is tightly linked to that of its partner - to test how ecological and life-history contexts shape the balance between cooperation and conflict.

Postdoctoral Research Associate, Avian Ecology Group University of Liverpool

April 2021 - October 2025

Drivers and consequences of foraging behaviour

I am analyzing long-term datasets from British Antarctic Survey and Centre d’Etudes Biologiques de Chizé, focusing on wandering and black-browed albatrosses. My research aims to understand how pair-level behaviors influence fitness and whether we can use foraging behavior to predict resource acquisition.

Movement decisions in albatrosses

Utilizing high-resolution GPS data alongside long-term behavioral assays, I have led projects on wandering albatrosses to explore (1) how personality traits affect foraging decisions at sea, and (2) the potential use of infrasound as a long-distance navigational cue.

ATLAS Wildlife Tracking

With support from a BBSRC Career Development Fellowship and NERC's Exploring the Frontiers grant, I have been collaborating with the ATLAS Wildlife Tracking team to establish the first ATLAS reverse-GPS tracking system in the Arctic. Ultimately, this system will allow for high-throughput, high resolution tracking of all major seabird species breeding in Svalbard.

DPhil Student, University of Oxford

September 2017 - March 2021

I worked in the OxNav research group for my BBSRC-funded PhD, where I investigated the mechanisms and consequences of coordinated parental care for two Procellariiform seabirds: the Manx shearwater and the black-browed albatross. I used precision biotelemetry devices in combination with fieldwork-based experiments and observations to investigate the decisions made by parents during breeding, and whether these are made cooperatively across the pair. My thesis is available to read online here.

Natasha Gillies

Research

February 2026 - present

April 2021 - October 2025

Get in touch at gilliesne [at] gmail.com