Multiple Factors vs. "Golden Mean" in Size Inheritance

Authors

R. A. Emerson, University of Nebraska-Lincoln

Date of this Version

1914

Citation

Science, New Series, Vol. 40, No. 1019 (Jul. 10, 1914), pp. 57-58

Comments

Copyright 1914 R. A. Emerson

Abstract

Groth's preliminary note on the "golden mean" in the inheritance of sizes in SCIENCE of April 17, 1914, pp. 581-584, deserves the attention of geneticists. Its publication is of such recent date that I need only call attention to one or two points that seem to me of particular moment.

In brief, Groth's hypothesis is that the mode

of inheritance in F_l not only of surfaces and

volumes, but also of linear dimensions is to be

expressed by √ab rather than by a + b /2

where a and b are parent sizes. The hypothesis

is based upon measurements of a large

number of tomato fruits of parental and F_l

plants. It will certainly be worth determining

whether Groth's expression fits size characters

in other plants. A hurried examination of

data, both published and unpublished, derived

from my own studies of seed size in beans and

maize, indicates that F_l sizes are nearer the

average than the geometric mean of the parent

sizes. But my object now is not to lay stress

upon any possible agreement or disagreement

between my results and those of Groth. It is

rather with the relation of Groth's hypothesis

to the idea of multiple factors that I am here

concerned.