What are the two key concepts of Darwinism ?

Options

A. Natural selection and branching descent
B. Branching descent and competition
C. Mimicry and natural selection
D. Variation and competition

Answer

**Step-by-Step Solution:**

1. **Understanding Darwinism**: Darwinism refers to the theory of biological evolution developed by Charles Darwin. It primarily focuses on how species evolve over time through natural processes.

2. **Identifying Key Concepts**: The two key concepts of Darwinism are:
- **Natural Selection**: This is the process by which individuals with favorable traits are more likely to survive and reproduce. It leads to the differential survival and reproduction of individuals due to differences in their phenotypes.
- **Branching Descent**: This concept explains how new species arise from common ancestors through a process of divergence. It suggests that all species share a common lineage and evolve over time.

3. **Evaluating Options**:
- **Option 1**: Natural selection and branching descent - This is correct as both are fundamental concepts of Darwinism.
- **Option 2**: Branching descent and competition - This is incorrect because while branching descent is a key concept, competition is not one of the main principles of Darwinism.
- **Option 3**: Mimicry - This is a phenomenon observed in nature but is not a key concept of Darwinism.
- **Option 4**: Variation and competition - Variation is important in the context of evolution, but competition is not a core concept of Darwinism.

4. **Conclusion**: The correct answer is **Option 1: Natural selection and branching descent**, as these two concepts encapsulate the essence of Darwin's theory of evolution.