Although the human species is a group of individuals very different from the rest of the animal forms, it is also possible to find variations in practically all the features of these. In fact, two people being identical is the exception, not the rule, and they are never identical in pure form; even among monozygotic twins, small mutations and variations in gene expression and behavioral learning make them distinguishable.

Next we will see a classification of the types of differences between people , delving especially into those that are psychological (i.e. behavioural) in nature.

Main differences between people

Since approximately the 19th century, the scientific community has had a great interest in objectively measuring differences between people , in all senses.Francis Galton, for example, in addition to being one of the main contributors to the birth of psychology in Europe, was dedicated to measuring the traits of people and predicting the possibility that their offspring would share them (something that fitted in with his defense of eugenics, by the way).

While the number of differences between people can be infinite, since there are an unlimited number of personal characteristics that can be isolated from each other, here are the main categories in which they are presented.

Physical differences

Physical differences can be recognized relatively easily by objective measurements, as they are found in the shape and size of the various organs of the body , or in biomarkers that can be recognized by analysis of microscopic components and that give information about the functioning of the organism.

These differences can be divided into two types: those that indicate the degree of health of the person, and those that do not. Among the former we find those that refer to the structure of the vital organs, for example, while height or eye colour are part of the second category.

Psychological differences

Psychological differences tell us about differentiated behaviour patterns between groups or individuals. In turn, these differences between people can be classified into several major subtypes.

Personality differences

This is possibly the most popular type of difference in psychology. It should be noted, however, that there is no single way of conceptualising differences between people in terms of their personality, as there are various theories and models that propose different ways of categorising these differences in personality dimensions and that, moreover, have different tests associated with them to measure these behavioural properties.

Thus, there is the model of the Five Great Personality Traits, another based on the test of the 16 personality factors, etc. All of them try to have internal coherence and to be predictive, but what one calls in one way, the other calls in another and relates it to other concepts.

Intelligence differences

Intelligence is one of the most important concepts of Differential Psychology, which is the branch of this science that investigates what individuals and groups are distinguished by.

Specifically, intelligence is defined as the set of cognitive skills that are directly involved in solving problems in real time, regardless of our habits and the contents we have memorized before. Thus, in theory all people can be placed in a distribution of intelligence scores from another construct called IQ, obtained through the intelligence tests.

However, some researchers have proposed that there are several intelligences, not just one. The most famous case is that of Howard Gardner, who through his theory of Multiple Intelligences presented the idea that each person could be good in one or several intelligences and bad in others. However, another author who presented a similar idea was Robert J. Sternberg, who presented his triarchic theory of intelligence: creative intelligence, practical intelligence and analytical intelligence.

Other researchers have also distinguished between conventional intelligence and emotional intelligence , which has to do with our ability to understand our own and other people’s feelings and emotions, and to regulate those that appear in our mind.

Differences in sexuality

Sexuality is also an area in which differences between people are expressed. In fact, the existence of homosexual, heterosexual and bisexual people is not the only aspect in which we differ in relation to this aspect. There are also differences between people regarding the level of sexual desire . Thus, while there are individuals who tend towards what has historically been called nymphomania, there are also those who are asexual, and between these two poles there is a great variety of nuances and differentiated positions between them.

Differences by gender identity

Gender identity is a psychological dimension that, despite being sometimes confused with sexual inclinations, is part of a differentiated category. Feeling male, female or neither of these two categories usually goes hand in hand with many other variations of behaviour.