Charles Darwin’s work has had a huge influence on the world, specifically in the sciences. While Darwin hypothesized and theorized many things some parts of his research were more salient to psychology than other aspects. Darwin wrote that humans and animals were descended from a common ancestor (this would develop into research in the 1900s and 2000s showing that humans and animals share the majority of their genes). Because Darwin stated that humans and animals have a lot in common, the field of comparative psychology (i.e., studying animals to learn about human behavior) increased in popularity. Scientists had studied animals for thousands of years and made inferences about humans from those animals but Darwin’s theories led to researchers making inferences about human behaviors such as learning, memory, emotions, and even social interactions based on observations and experiments with animals.
Darwin’s research also led to research in psychology of individual differences. Before his theories, most researchers were trying to understand humans by looking at averages and similarities between people. They were just trying to understand the basic underlying constructs of human behavior. After Darwin, psychologists began investigating individual differences. It was not many years before the first modern intelligence test was developed by Binet in France. Intelligence is one area where many researchers focus on individual differences. Some psychologists are interested in what human traits make some people more successful than others. This is based largely on Darwin’s idea of natural selection where the strongest, adaptive, or creative species survive and other ones do not.
Darwin’s theories also had a large impact on psychology in general; much of psychology today has strong biological underpinnings. This traces largely back to Darwin. Psychologists often try to explain psychological concepts in light of biological processes. Some schools of psychology are almost strictly Darwinian, such as ethological psychology (the most famous 20th century ethological psychologist is Konrad Lorenz) and evolutionary psychology. Even though Darwin was not a psychologist, his theories have had a large and lasting impact on the field of psychology.