The increased number and density of species in the region of ecotone is called

Options

A. Edge effect
B. Sympatric speciation
C. Dominance
D. Abundance

Answer

**Step-by-Step Solution:**

1. **Understanding Ecotone**:
- An ecotone is a transitional zone between two different ecological communities. It is where two ecosystems meet and interact, leading to a unique environment that can support a diverse range of species.

2. **Characteristics of Ecotone**:
- In an ecotone, you will find species from both adjacent communities. For example, where a forest meets a grassland, the ecotone will host species from both ecosystems.

3. **Increased Species Density**:
- In the ecotone, the number and density of species often increase compared to the surrounding areas. This phenomenon occurs because the ecotone provides a variety of habitats and resources that can support a larger number of species.

4. **Terminology**:
- The increased number and density of species in the region of an ecotone is referred to as the "edge effect." This term describes how the boundaries between different ecosystems can enhance biodiversity.

5. **Conclusion**:
- Therefore, the correct answer to the question is that the increased number and density of species in the region of ecotone is called the "edge effect."

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