Ethology also the discontinuance of undesirable behaviours. The term "ethology" derives from the Greek language: ἦθος, "ethos" meaning "character" and , "-logia" meaning "the study of". The term was first popularized by American myrmecologist (a person who studies ants) William Morton Wheeler in 1902. Because ethology is considered a topic of biology, ethologists have been concerned particularly with the evolution of behaviour and its understanding in terms of natural selection. In one sense, the first modern ethologist was Charles Darwin, whose 1872 book "The Expression of the Emotions in Man and Animals" influenced many ethologists. He pursued his interest in behaviour
The Expression of the Emotions in Man and Animals induce directly opposing movements. Finally, he discusses a "direct action of the nervous system", in which an overflow of emotion is widely discharged, producing more generally expressed emotions. This is followed by a section (three more chapters) on modes of emotional expression peculiar to particular species, including man. He then moves on to the main argument with his characteristic approach of astonishingly widespread and detailed observations. Chapter 7 discusses "low spirits", including anxiety, grief, dejection and despair; and the contrasting Chapter 8 "high spirits" with joy, love, tender feelings and devotion. Subsequent chapters include considerations of "reflection and meditation" (associated