What was the most significant trend in the evolution of modern man (Homo sapiens) from his ancestors?

Options

A. Shortening of jaws
B. Binocular vision
C. Increasing brain capacity
D. Upright posture

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the most significant trend in the evolution of modern humans (Homo sapiens) from their ancestors.

2. **Analyzing the Options**:
- **Option A: Shortening of jaws**: This option suggests that modern humans have shorter jaws compared to their ancestors. However, both modern humans and their ancestors exhibit relatively short jaws, making this option incorrect.

- **Option B: Binocular vision**: This refers to the ability to perceive depth and three-dimensional structure due to the positioning of the eyes. Both modern humans and their ancestors possess binocular vision, so this option is also incorrect.

- **Option C: Increasing brain capacity**: This option indicates that modern humans have a significantly larger brain compared to their ancestors. The average cranial capacity of modern humans is about 1330 cm³, which is approximately twice the size of that of chimpanzees and gorillas. This significant increase in brain size is a defining characteristic of modern humans, making this option correct.

- **Option D: Upright position**: This option refers to bipedalism or the ability to walk upright. Both modern humans and their ancestors have exhibited this trait, so this option is incorrect.

3. **Conclusion**: After evaluating all the options, the most significant trend in the evolution of modern humans from their ancestors is **Option C: Increasing brain capacity**.

**Final Answer**: The most significant trend in the evolution of modern man (Homo sapiens) from his ancestors is increasing brain capacity.

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