Variation is the differences that exist between individuals of the same characteristics in common, by which they can be recognized as members of the same species. At the same time, members of the same species have individual differences. For example, all the students in a school belong to the same human population and therefore have the same human features, but each student differs from the others.
TYPES OF VARIATION
There are two types of variations: morphological variation and physiological variation.
MORPHOLOGICAL VARIATION
Morphological variation refers to the noticeable physical appearance of individuals of the same species. This physical appearance helps us to identify individuals of a population. In humans, morphological variations include: height of the body, shape of various parts of the body such as head, mouth, nose, eyes, ears, legs and hands, fingerprint, size of various parts of the body such as head, eyes, hands, neck, color of parts of the body such as the skin, eyes, and hair.
PHYSIOLOGICAL VARIATION
Physiological variation relates to the differences in the ways individuals of the same species behave or react to conditions in their environment. It also relates to the functioning of the body.
Differences of variations in behavior by which organisms can be grouped into two or more classes within a population, without any graduation in between or intermediates among them are called discontinuous variations. Example of physiological or discontinuous variations in human beings are:
- Behavior: The way individuals behave under normal circumstances varies considerably. People may be grouped as being: Aggressive or non-aggressive, excitable or calm, timid or brave, caring or uncaring, intelligent or stupid. Many behavior patterns, though may be inherited, are also controlled by hormones such as thyroxine, adrenaline, and sex hormones.
- Ability to roll the tongue: Some people have the ability to roll their tongue when it is pushed out of the mouth while others cannot.
- Ability to close one eye and keep the other open.
- Ability to move the ears without moving the head.
- Differences in blood group.
- Fingerprints.
APPLICATION OF VARIATIONS
Variation has wide applications in human life. These applications include:
- Crime detection
- Blood transfusion
- Determination of paternity
- In medicine
- Classification of human race.
In conclusion, variation is a fundamental aspect of life that impacts various aspects of human existence. Understanding the different types of variations and their applications can lead to significant advancements in various fields, such as medicine, crime detection, and the classification of human race. By recognizing and embracing the diversity that variation brings, we can work towards a more inclusive and understanding society.