Fight and flight: Behavioural drivers and evolutionary consequences of resource competition in birds

Animal competition determines the allocation of resources required for individual survival and reproductive success. These consequences of competition drive selection for traits that confer competitive advantages. While previous studies have quantified effects of fundamental behaviours on competition, research on more complex competitive behaviours has only recently emerged due to improvements in data collection and analysis methods. My research aims to advance our understanding of how resource competition drives the evolution of extreme flight anatomy and how complex flight and social behaviours influence competition in birds, a group of species that vary in competitive abilities. First, I investigate the evolution of flight apparatus morphologies related to high-performance flight in hummingbirds through the lens of species foraging competition. I show that variation in mass-adjusted keel and humerus morphologies is not explained by species differences in foraging strategies, but instead explained by sex differences presumably driven by within-species competition. Next, I assess the intrinsic drivers of unpredictable flight in hummingbirds, a complex behaviour expected to facilitate success during resource competition. I find that species with the most unpredictable flight demonstrate strong transitional and rotational maneuverability performance, while maneuverability itself has little to no effect on moment-to-moment changes in unpredictability. Instead, I show that unpredictable flight is achieved during slow flight, highlighting the nuanced relationships among intrinsic drivers of complex locomotor behaviours. Then, I examine the influence of social behaviour on the outcome of among- and within-species resource competition in North American birds. I show that more social species are weaker competitors than less social species, but demonstrate increased competitive success when in the presence of other conspecifics, all at the cost of increased conspecific competition. Finally, I discuss alternative ecological and evolutionary factors that may drive differences in resource competition abilities among birds, and highlight opportunities to integrate modern experimental approaches in future research to enrich our understanding of the dynamics of avian resource competition. Overall, my thesis research expands our knowledge of the evolutionary consequences of competition on extreme morphologies, the biomechanical facilitators of competitive locomotor behaviour, and the influence of social behavioural strategies on the outcome of resource competition.

Name thesis:degree_name

Doctor of Philosophy (Ph.D.)

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Biology

Grantor dc:publisher

Carleton University

Year dc:date.issued

2024

Author dc:creator

• Berberi, Ilias

Statement dc:rights

• Copyright © 2024 the author(s). Theses may be used for non-commercial research, educational, or related academic purposes only. Such uses include personal study, distribution to students, research and scholarship. Theses may only be shared by linking to the Carleton University Institutional Repository and no part may be copied without proper attribution to the author; no part may be used for commercial purposes directly or indirectly via a for-profit platform; no adaptation or derivative works are permitted without consent from the copyright owner.

Language dc:language.iso

en

DOI

10.22215/etd/2024-16275

OAI identifier oai:identifier

oai:carleton.scholaris.ca:20.500.14718/43146