Unisexual (all-female) lizards of the genus Cnemidophorus are well suited for research in oogenesis, embryogenesis, nutrition, immunology, sex determination, genetics and the effects of aging and exposure to pathogens and chemicals, in addition to evolutionary biology. Individuals produce clones by means of parthenogenesis, and both diploid and triploid parthenogens exist. In addition, there are closely related bisexual (gonochoristic) species of Cnemidophorus. Advantages and disadvantages of maintaining laboratory colonies of Cnemidophorus are discussed.