An example of bottleneck effect is:

Options

A. 1)Pitcairn island population
B. 2)Longneck in giraffes
C. 3)Polydactylic dwarf individuals in the Old order Amish population of Lancaster of USA
D. 4)Limbless snakes

Answer

**Step-by-Step Solution:**

1. **Understanding the Bottleneck Effect**: The bottleneck effect is a form of genetic drift that occurs when a population's size is significantly reduced for at least one generation. This reduction can result from various factors such as natural disasters, disease, or human activities.

2. **Identifying Characteristics**: In the bottleneck effect, the surviving population may not represent the genetic diversity of the original population. This can lead to a loss of genetic variation and can affect the population's ability to adapt to environmental changes.

3. **Analyzing the Options**:
- **Option 1: Pitcairn Island Population**: This population may have experienced genetic drift but is not a classic example of the bottleneck effect.
- **Option 2: Long Neck in Giraffes**: This is an example of sexual selection rather than a bottleneck effect.
- **Option 3: Polydactilic Dwarf Individuals in the Old Order Amish Population of Lancaster, USA**: This is a classic example of the bottleneck effect. The Amish population has a reduced gene pool due to a small founding population, leading to specific genetic traits becoming more common.
- **Option 4: Limbless Snakes**: This is an example of adaptation rather than a bottleneck effect.

4. **Conclusion**: After analyzing all the options, the correct example of the bottleneck effect is **Option 3: Polydactilic dwarf individuals in the Old Order Amish population of Lancaster, USA**.

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