What do you mean by ecotone?

Explanation

### Step-by-Step Solution:

1. **Definition of Ecotone**: An ecotone is a transitional area between two different ecosystems. It is where two ecosystems meet and interact.

2. **Characteristics of Ecotones**: Ecotones do not have rigid or fixed boundaries. This means that the transition from one ecosystem to another is gradual rather than abrupt.

3. **Overlap of Ecosystems**: Because ecotones lack rigid boundaries, the species and characteristics of the two ecosystems can overlap. This overlap can lead to a unique set of species and environmental conditions that are different from either of the adjoining ecosystems.

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