Gregor Mendel and the Seven Genes (1)

Abstract Gregor Mendel, Thomas Hunt Morgan and experiments in classical geneticsIn the middle of the 19th century, Gregor Mendel performed a series of crosses with pea plants to investigate how hybrids are formed. Decades later, Thomas Hunt Morgan finalized the theory of classical genetics. An important aspect of Mendel’s and Morgan’s scientific approach is that they worked in a systematic, experimental fashion. But how did these experiments proceed? What is the relation between these experiments and Mendel’s and Morgan’s explanatory theories? What was their evidential value? Using present-day insights in the nature of experimentation I will show that the answer to these questions is fascinating but not obvious. Crossings in classical genetics lacked a crucial feature of traditional experiments for causal discovery: manipulation of the purported causes. Hence they were not traditional, ‘manipulative’ experiments, but ‘selective experiments’.

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6. Genes

Philosophy of Biology: A Very Short Introduction ◽

10.1093/actrade/9780198806998.003.0006 ◽

2019 ◽

pp. 83-100

Author(s):

Samir Okasha

Keyword(s):

Molecular Genetics ◽

Precise Definition ◽

History Of Genetics ◽

History Of ◽

Gregor Mendel ◽

The 1950S ◽

Classical Genetics

There is no satisfactory one-line answer to the question ‘what exactly is a gene?’. The reasons why a precise definition is elusive are particularly interesting, and raise a number of philosophical subtleties. ‘Genes’ delves briefly into the history of genetics in order to understand them. It first looks at the work of Gregor Mendel in the 1860s and then the era of classical genetics in the 1920s and 1930s. It then moves on to molecular genetics, which came to fruition in the 1950s. How does the gene of Mendelian or classical genetics relate to the gene of molecular genetics? This question has long occupied philosophers of biology.

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