K-strategist species, or K-selected species, are species that focus more on a few offspring rather than focusing less on many offspring. They generally have long generations and few offspring. The parents usually spend most of their energy nurturing and protecting offspring. The children are usually fairly large and mature slowly. These species generally do well in competitive environments in which their population near the carrying capacity of the environment. They also do better in environments with consistent environmental conditions. They usually consist of large mammals, birds, and large, long-lived plants.