At the beginning of the twentieth century, geneticists
A) thought that inheritance was fundamentally discontinuous.
B) argued that Mendelian genetics supported Darwin's idea that adaptation occurs through the accumulation of small variations.
C) agreed that evolution proceeded by the gradual accumulation of small changes.
D) believed that genes had no discernible effect on phenotypes.

Question

Quizplus · Accepted Answer

At the beginning of the twentieth century, geneticists believed in the concept of "discontinuous inheritance," which meant that traits were determined by discrete units passed down from parents to offspring, rather than gradual changes over time. This theory was based on the work of Mendel, whose discoveries of the laws of inheritance were only just beginning to be understood at the start of the century. Therefore, Option A is the best choice.

At the Beginning of the Twentieth Century, Geneticists