The revised draft begins:
The predominant current-day meaning of genotype is some relevant part of the whole genome, the DNA passed to the organism by its parents. The phenotype is the physical and behavioral characteristics of the organism, for example, size and shape, metabolic activities, and patterns of movement. The distinction is especially important in evolutionary theory, where the survival and mating of organisms depends on their traits, but it is the DNA, held to be unaffected by the development of the traits over the life course, that is transmitted to the next generation.
- This was not the meaning of the terms or the reason for making the distinction when it originated with Johannsen (1911).
- Once the current-day meanings above are adopted, philosophical discussion shifts more to the genotype->phenotype relationship—how genotypes and other factors cause phenotypes. This focus or starting point is evident in many sections of the previous version of the entry and in most of the publications that the editors suggested we address in the revision.
- Even when the current-day meanings above are adopted, other meanings of the terms persist. To help readers, it is better to acknowledge, rather than exclude by definitional dictate, the other meanings and attendant confusions from the coexistence of different kinds of meanings.
- Looking at the evolution of the terms since their origin is a matter for historical inquiry, which is beyond the scope of this entry. However, it seemed that a helpful and stimulating way to address the significance for philosophers of the genotype-phenotype distinction was to a) note the special conditions in which the terms and their distinction were originally formulated—the material practices of control over biological materials and conditions advanced in modern experimental biology and agricultural breeding; b) review continuations and extensions of that control; and c) consider possible concepts, methods, and models though which what has been de-emphasized could be brought back and re-integrated into the scientific analysis.
- Giving attention to control and reintegration can be seen as giving attention to abstraction, but the literature on abstraction did not provide a helpful framing for this entry on the genotype-phenotype distinction.
(See previous posts on the evolution of the revision of the entry on genotype-phenotype distinction.)
Johannsen, W. (1911). “The Genotype Conception of Heredity.” The American Naturalist 45: 129-159.