carnivores, requiring nutrients from arthropods or other small reptiles. Diet can also vary depending on age, sex, as well as seasonal changes. In the case of younger lizards, they consume the same kinds of foods, specifically insect species, that adults do, but since younger lizards and adults differ in body size and weight, the amount of food intake tends to vary. On the other hand, male and female adults are similar in terms of their sizes and the amounts of food ingested but exhibit drastic differences in the kinds of foods that they eat. From an evolutionary standpoint, these sexual differences in diet may act to reduce intra-species competition for resources, whereby females and males do not need to fight for the same type of food. Moreover, changes in season can drastically affect their diets as well. Cultural impact The collared lizard is the state reptile of Oklahoma, where it is known as the mountain boomer. The origin of the name "mountain boomer" is not clear, but it may be traceable to settlers traveling west during the Gold Rush. One theory is that settlers mistook the sound of wind in canyons for the call of an animal in an area where the collared lizard was abundant. In reality, collared lizards are silent. Behavior Collared lizards are diurnal; they are active during the day, and spend most of their time basking on top of elevated rocks or boulders. As a highly territorial species, they remain hyper-vigilant, scanning for predators or intruders, ready to sprint or fight when necessary. Generally, males are more active than females, as the former engage in more chase, fight, display, and courtship behaviors while the latter exhibit basking and foraging behaviors. The collared lizard in the wild has been the subject of a number of studies of sexual selection; in captivity if two males are placed in the same cage they will fight to the death. Females, on the other hand, do not demonstrate aggressive behaviors as frequently as males, experiencing less intra-species competition with other females. Social Behavior In an effort to monopolize as many female mates as they can, male C. collaris viciously defend their exclusive territories through aggression, patrolling activities, and displays. These territories provide ample resources and shelter the harem of females claimed and protected by the male territory owners. However, when agonistic interactions between male rivals escalate to violent fights, both lizards