Lamarckism was finally rejected mainly because
- A. changes in body cells do not alter the genes carried in the germ cells
- B. organisms were found not to vary at all
- C. the fossil record showed no change over time
- D. no organ was ever found to degenerate through disuse
Explanation
Weismann's germ plasm idea, supported by his experiment of cutting off the tails of mice for many generations without shortening the tails of their offspring, showed that somatic changes leave the gametes untouched. Since only the gametes carry information to the next generation, an acquired character cannot be inherited. Variation and fossil change are both real and are the very evidence evolution rests on.