BIOLOGICAL DETERMINISM IN HUMANS AND ANIMALS - BIOLOGY - 2025

The biological determinism is a theory that the behavior of human beings is determined by genes, ie it is an innate and inherited factor. According to this theory, the intellectual capacity, the way of responding and the development possibilities of each human being are controlled by their genetic information.

Determinists maintain, among other things, that racism, social inequality, aggressiveness or differences between the sexes are due to inherited factors, as is the case with physical characteristics.

Painting by Sir Francis Galton. Precursor of eugenics. Taken and edited from: National Portrait Gallery.

The dominant social groups have tried to use biological determinism to justify abuse in the exercise of their authority and to perpetuate oppression over other social groups considered to be less favored.

Historical background

Germ plasma

This theory, proposed by August Weismann in 1892, supported the existence of two types of cells in multicellular organisms. These cells were somatic and germ cells. But he also maintained that the information contained in the germ plasm determined the characteristics of the adult organism.

This information was unalterable and nothing could affect it, remaining that way unchanged for the next generation.

Eugenics

Eugenics, or eugenics, was developed by Francis Galton, Charles Darwin's cousin. At that time it was argued that problems such as alcoholism, criminality or sexual disorders were inheritable characters, as well as undesirable physical malformations.

To reduce or eliminate these defects (associated with lower classes and / or minority ethnic groups), eugenic control of the population emerged. One of the mechanisms used was the compulsive sterilization of people considered genetically undesirable.

In 1904, Galton advocated the creation in England of the "National Eugenics", defined as the study of all social media that would allow the racial qualities of future generations to be affected positively or negatively, on the physical as well as the mental plane, in order to which was created the Eugenic Registry Office.

Polygeny

Theory from the mid-19th century, whose main defenders were the French anatomist Georges Cuvier and the Swiss-American creationist Jean Louis Rodolphe Agassiz. The first of these defended the belief that the black race was inferior and was against any belief that all human beings had the same origin.

Agassiz, for his part, went further than his tutor Couvier and proposed that the different human races were really subspecies or, more likely, distinct species.

This belief was embodied in the theory of the existence of different areas of creation, which separated species or subspecies, and their ancestors, according to their geographical distribution.

Craniometry

Craniometry is the study of the internal cranial volume (cranial capacity) and its relationship to the intellect and character. The pioneers in this type of study were the American Samuel George Morton and the French Paul Broca.

The intention, never achieved, was to demonstrate the supremacy of the white race over other races, based on a supposed greater cranial capacity. Despite the doubtful and refutable results, they were used to justify racism and to impede the right of women to vote.

Live head measurements (craniometry), device invented in 1913. Taken and edited from Wikimedia Commons

Heritability of intelligence quotient (IQ)

American researchers HH Goddard, Lewis Terman and Robert Yerkes used IQ tests to measure mental ability. These tests were used under uncontrolled conditions, unconsciously or consciously.

The results "demonstrated" the supremacy, not only of the white race, but of the white-American race, and were used to oppose the immigration of people from Eastern Europe to the United States.

They also "showed" that black children were, by nature, less capable than their white peers at solving cognitive problems. Because of this, no educational effort could eliminate the differences between these two races.

Sociobiology

With the theories of the selfish gene and the altruistic gene, human behavior seems to escape the free will of the human being himself, and becomes the responsibility of his genes.

Sociobiology emerges then as a hybrid discipline of sociology and biology. With it, scientists try to explain human behavior from a point of view that includes both disciplines. His main work is perhaps represented by the work Sociobilogía: La nueva synthesis, by EO Wilson (1975).

Biological determinism as a scientific theory

Starting from the principle that both the intellectual capacity, the way of responding and the development possibilities of each person are affected by their genes, determinists have established several conclusions, among them:

In the first place, the success of the different social classes, and of their members, is due to an innate differential intelligence, genetically controlled. Second, racial social differences are due to genetic differences, which in this case provide advantages to whites over blacks.

Another conclusion is that men are genetically better adapted than women to dangerous conditions or to eventual damage, because their chromosomes have a better capacity for synthesis, rationality, aggressiveness and leadership capacity.

Additionally, hereditary factors are responsible for social defects such as poverty and extreme violence.

Finally, and hand in hand with sociobiology, it also establishes that warmongering, territoriality, religion, male domination, conformism, among others, have been imprinted in our genes by natural selection.

Stephen Jay Gould, in his work The Mismeasure of Man, analyzes the history of biological determinism, first refuting the antecedents on which this theory has built its foundations (craniometry, IQ, etc.).

This same author points out three methodological problems that generally affect work on determinism:

In the first place, the fascination with measuring and quantifying has led them to suppose that if any variable is assigned a number, it is made scientifically valid to be evaluated in all contexts.

On the other hand, the belief that any quality is a valid variable, simply because it is recognized as such (eg intelligence).

Finally, the a priori presumption that all the variables under consideration are heritable.

Biological determinism in animals

There are no conclusive scientific works that demonstrate the existence of biological determinism in animals. However, some authors suggest that in these, both sexual orientation and reproductive behavior are genetically controlled.

Sexual orientation and reproductive behavior are controlled by the same hormone throughout ontogenetic development. Additionally, these hormones act on the same brain region for both variables. These facts have been used to suggest the biological determinism of homosexuality in humans and animals.

But perhaps the best evidence, in the opinion of the author of this article, of the non-existence of biological determinism, can be found precisely in animals, more specifically in social insects.

In bees, for example, all individuals at birth have the same development possibilities. However, upon reaching adulthood the vast majority will develop as workers, and a few, very few, as queens.

The final fate of the larvae is not genetically determined. On the contrary, a "special" diet will allow them to develop as queens. On the other hand, a "normal" diet will lead them to be simple workers.

Image of a queen bee and her workers. Taken and edited from: Sabinehoe.

References

1. J. Balthazart (2011). The Biology of Homosexuality. Oxford University Press.
2. On Wikipedia. Recovered from en.wikipedia.org
3. RC Lewontin (1982). Biological Determinism. The Tanner Lectures on Human Values. The University of Utah
4. SJ Goul (1981). The Mismeasure of Man. WW Norton & Co.
5. GE Allen (1984). The Roots of Biological Determinism. Journal of the History of Biology.
6. JL Graves Jr. (2015) Great Is Their Sin: Biological Determinism in the Age of Genomics. The Annals of the American Academy of Political and Social Science.