Interactions with the physical and social aspects of an animal’s surroundings direct the trajectory of local adaptation and can lead to tremendous diversity within and across taxa. In my dissertation, I explored how interactions between lizards and their environment lead to morphological, behavioral, and ecological diversity. First, I examined how a common, but unexplored habitat characteristic, perch flexibility, affects jumping performance of an arboreal lizard. I found that in the lab, green anole lizards (Anolis carolinensis) did not take advantage of the natural recoil of the flexible perches, and suffered decreased jump distance and takeoff speed as a consequence. Next, I extended my inquiry into how this habitat characteristic affects multiple aspects of behavior and morphology of the lizards in nature, given the potential performance costs associated with flexible perches. Most strikingly, I found that while green anoles used a range of perches in their habitat for most activities, they selectively jumped from relatively non‐flexible perches. Then, I sought to more broadly understand the effects of habitat on the whole organism. I examined associations between habitat structure and complexity on male and female sexual and non-sexual traits, as these would reflect habitat effects on locomotion, foraging ecology, and social interactions. I found that while there was no association between habitat structure and variation in most traits I examined, male body condition decreased with decreasing vertical vegetative complexity. Finally, I focused on the role of social interactions in increasing morphological diversity. I examined the association between genital morphology and male mating type in an alternative mating strategy population of the terrestrial lizard Uta stansburiana. I found that male mating types differed in genital length and complexity, suggesting that strong sexual selection may drive morphological differentiation within populations. Together, my work shows the importance of animal-environment interactions as drivers of diversity and contributes to the broader fields of sexual selection, behavior and evolutionary ecology.