Who proposed the ecological pyramids ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Ecological Pyramids**: Ecological pyramids are graphical representations that show the distribution of various components in an ecosystem. They can represent the number of organisms, biomass, or energy at different trophic levels, typically arranged in a triangular shape.

2. **Identifying the Concept Origin**: The question specifically asks about the origin of the concept of ecological pyramids. This involves determining who first proposed or introduced this concept in ecological studies.

3. **Researching the Contributor**: Upon reviewing the history of ecological studies, it is noted that the concept of ecological pyramids was introduced by a biologist.

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