During the argumentation of questions of biological determinism, the author supports his idea with numerous examples. He gives examples of supporters of bio determinism and outlines that these examples are not reliable. One of the fallacies of biological determinism is the result of IQ testing. The author state that this is completely fallacious because there is no connection between the variation that can be ascribed as genetic differences and whether an IQ performance was affected by environment and by how much. IQ measures little more than a person' s ability to take a test.
Scores increase dramatically as a person is trained or familiarised with a test.
It means that an IQ level does not depend on the intellectual abilities of parents but on the manner of studying and preparation that can be considered as environmental changes. For the author, there is a casual relationship between genetic and environmental differences. He gives us an example of a fruitflies with more bristles under the wing on the left side than on the right side. He says that these differences are caused by random chances of cell during growth and development and that every organism is a unique combination of genes and environmental random chances. The author argues that the proportion of variation in genes is not fixed properly, but one that varies from environment to environment.