The eyes of first primates faced forward. All the following are advantages of these, except

Options

A. Binocular vision
B. This gave the primates excellent depth preception, which enabled them to judge distances accurately when moving through the trees
C. The field of vision of two eyes is different
D. Binocular vision results in three- dimensional image

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the advantages of having forward-facing eyes in the first primates and specifically requests to identify the one option that is NOT an advantage.

2. **Analyzing the Options:**
- **Option A:** Binocular vision.
- This is an advantage because forward-facing eyes allow for overlapping fields of vision from both eyes, leading to better depth perception.
- **Option B:** Excellent depth perception.
- This is also an advantage as it helps primates judge distances accurately, which is crucial for navigating through trees.
- **Option C:** The field of vision of two eyes is different.
- This statement is incorrect. The field of vision of two eyes is similar, not different, when both eyes are open. This is the option we are looking for.
- **Option D:** Binocular vision results in a three-dimensional image.
- This is an advantage because binocular vision allows for the perception of depth and three-dimensionality.

3. **Identifying the Incorrect Option:**
After analyzing all options, we see that Option C is the only one that does not represent an advantage of forward-facing eyes in primates.

4. **Conclusion:**
The answer to the question is Option C: "The field of vision of two eyes is different."

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