A Scientist kept 69 generatios of Drosophila in darkness even after that the files had normal eyes, this disprovs the law of :

Options

A. Synthetic theory
B. Natural selection
C. Germplasm theory
D. Acquired characters are inherited

Answer

**Step-by-Step Solution:**

1. **Understanding the Experiment**: A scientist kept Drosophila (fruit flies) in darkness for 69 generations. The expectation based on certain evolutionary theories is that if an organ (in this case, eyes) is not used, it may become vestigial or disappear over generations.

2. **Theoretical Background**: The question revolves around the concept of acquired characteristics, which is a key idea in Lamarck's theory of evolution. According to Lamarck, traits that are used become stronger and are passed on to the next generation, while traits that are not used may diminish or disappear.

3. **Observation of Results**: After 69 generations in darkness, the Drosophila still had normal eyes. This observation contradicts Lamarck's theory, which would predict that the eyes would have diminished or disappeared due to lack of use.

4. **Conclusion**: Since the eyes of the Drosophila remained normal despite being in darkness for many generations, this disproves Lamarck's idea that acquired characteristics (like the disuse of eyes) can be inherited. Instead, it supports the idea that traits are not influenced by the environment in the way Lamarck suggested.

5. **Final Answer**: The law that is disproved by this experiment is Lamarck's theory of acquired characteristics.

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