Ontogenies refers to the processes of development and growth of an organism over time. Some synonyms for ontogenies include developmental stages, life cycle, maturation, growth cycle, and evolutionary progression. These words describe how an organism changes over time and how it adapts to the environment. Each term emphasizes different aspects of development. Developmental stages refer to different periods of growth, maturation points or milestones. Life cycle emphasizes the cycle of birth, growth, and death that an organism undergoes. Maturation emphasizes the physiological and psychological changes that occur while the term growth cycle emphasizes physical growth. Evolutionary progression refers to changes in a species over generations.