Ueber Erblichkeit in Populationen und in reinen Linien Ein Beitrag zur Beleuchtung schwebender Selektionsfragen

Abstract

PROF. JOHANNSEN has set himself a hard task, namely, the reconciliation of the views of Prof. de Vries on mutations with those of the biometric school, particularly with the Galtonian theory of regression. We say a hard task, because to perform the task of reconciliation requires, on the one hand, an intimate knowledge of the mathematical theory of statistics, and on the other a power of clearly defining the exact biological points which are at issue. It is not an easy matter to distinguish between a so-called mutation and an extremely improbable variation; indeed, the utmost caution is needed when we remember that in every case of continuous variation it has been shown theoretically that the extreme variations in populations of even many thousands must be separated by wide intervals, the wider the more extreme the variations.¹ Clearly it is practically impossible to distinguish straight off between a “mutation” and an extreme variation in the biometric sense. Both parties would probably agree that only observation of the results of propagating from the individual thus classified could serve as a criterion between the two views.

Ueber Erblichkeit in Populationen und in reinen Linien. Ein Beitrag zur Beleuchtung schwebender Selektionsfragen.

By W. Johannsen. Pp. 68. (Jena: G. Fischer, 1903.)