DETERMINING HOW ANTHROPOGENIC CHANGE FILTERS BIOLOGICAL COMMUNITIES AND HOW SPECIES MODIFY THEIR TRAITS IN RESPONSE TO URBANIZATION

Abstract

Humans are significantly altering the environment at an alarming pace, leading to a reduction in species diversity. This transformation has created modified habitats where some species struggle to survive, while a few others not only manage to survive but thrive. One of the most drastic forms of habitat modification is urbanization, which is spreading worldwide and contributing to the decline of biodiversity. Urbanization has given rise to urban-tolerant species that differ ecologically from species that avoid urban areas across various niche dimensions. These urban-tolerant species must adapt to changes in food sources, microhabitat conditions, and alterations in physical habitat structures. The focus of my dissertation is to investigate the impact of urbanization on morphological and dietary changes in lizard populations. First, I aim to identify and characterize specific morphological traits associated with urbanization by determining how ecological filters are shaping urban lizard communities. Secondly, I will determine if lizard species inhabiting urban environments are undergoing phenotypic changes and categorize these changes as convergent, divergent, or idiosyncratic. Lastly, I will assess whether dietary niche breadth is expanding or contracting in urban environments compared to natural ones.