An entomologist is a biologist who studies insects. Insects make up 75% of all animal species. They are important to ecosystems, however many also carry diseases and destroy plant life, sometimes destorying an entire species or forest. Some entomologists work on ways to eliminate the harmful insects while not harming the environment. Other entomologists work for the government in agriculture or food inspection. Entomologists can also work in research studying the life cycle of insects, processes or behavior.