Natural-history studies represent the observational stage of the scientific method, and the single greatest discovery in biological sciences, evolution by natural selection, was based largely on a vast amount of natural-history information collected by Charles Darwin. I briefly review natural-history observations that I have made during my career that led to discoveries in life-history theory, placentation in New World Mabuya that rivals that of eutherian mammals, social behavior in the North American clade of five-lined skinks, and the relationship of ecological traits of lizards globally to their evolutionary history (phylogeny). Gifted collaborators provided the intellectual interplay that led to these discoveries, and they certainly deserve as much credit as I do. I briefly comment on what I consider to be frontiers in herpetology that involve combining phylogenetic hypotheses with natural-history data. In a final comment, I encourage those among us who are able to spend extended time periods in the field to collect as much natural-history data as possible, because these data describe reality, and, as theories and phylogenies evolve, the kinds of basic data that led to Darwin's theory of evolution by natural selection can be applied again and again.