Long neck of giraffe is stabilized in its evolution by

Options

A. Centrifugal selection
B. Centripetal selection
C. Adaptive radiation
D. Directional selection

Answer

To solve the question regarding how the long neck of the giraffe is stabilized in its evolution, we can follow these steps:

### Step 1: Understand the Options
The question presents four options related to the evolutionary stabilization of the giraffe's long neck:
1. Centrifugal selection
2. Centripetal selection
3. Adaptive radiation
4. Directional selection

### Step 2: Analyze Each Option
- **Centrifugal Selection**: This term is not commonly used in evolutionary biology and does not apply to the giraffe's neck.
- **Centripetal Selection**: This type of selection occurs under stable environmental conditions, where certain traits become more common because they are advantageous in that environment.
- **Adaptive Radiation**: This refers to the diversification of a group of organisms into forms filling different ecological niches, which does not specifically relate to the stabilization of a single trait like the giraffe's neck.
- **Directional Selection**: This occurs when environmental changes favor one extreme phenotype over others, leading to a shift in the population's traits.

### Step 3: Identify the Correct Answer
Given the analysis:
- The long neck of the giraffe is a trait that has been stabilized through **centripetal selection**, as it has been advantageous in a stable environment where giraffes can reach higher foliage for feeding.

### Step 4: Conclusion
The correct answer to the question "Long neck of giraffe is stabilized in its evolution by" is **Centripetal Selection**.