Final answer:
Continuous variation describes the range of trait values with small differences, seen in human characteristics like height and skin color. Biological race is scientifically unsupported due to the high level of genetic diversity within so-called racial groups compared to between them. Race is a social construct rather than a biologically valid classification.
Step-by-step explanation:
Continuous Variation and Biological Race
Continuous variation refers to the inheritance pattern in which traits display a range of values with small gradations, as opposed to distinct categories or large gaps. This can be seen in human characteristics like height, skin color, and eye color that result from the interaction of many genes. Biological race as a concept is often debated in this context because the variation within groups traditionally classified by race is often as great or greater than the variation between these groups. Hence, the concept of race fails to meet the scientific criteria for a biological classification.
Mendel's work in genetics revealed that the blending of traits, which aligns with the pattern of continuous variation, could not explain some genetic outcomes. Instead, discrete traits and the roles of multiple genes in determining characteristics were identified. Furthermore, studies have consistently shown that there is no scientifically justifiable way to divide humans into discrete racial categories based on biology, as all human traits vary along a spectrum and there is more genetic diversity within racial groups than between them.
It's important to note that while race may lack a biological basis, it remains a significant social construct with real-world implications, influencing areas such as social interaction, discrimination, and policy. However, the biological aspect of race is now understood to be a weak construct that does not align with the complexities of human genetic variation.