---
title: "Trophic Cascades — AP Bio Definition & Exam Guide"
description: "Trophic cascades are ripple effects through a food web when a top predator's population changes, shaping community structure (AP Bio Unit 8.5)."
canonical: "https://fiveable.me/ap-bio/key-terms/trophic-cascades"
type: "key-term"
subject: "AP Biology"
---

# Trophic Cascades — AP Bio Definition & Exam Guide

## Definition

Trophic cascades are ecological phenomena triggered by changes in top predators' population size that cause ripple effects down through lower levels of the food chain.

## Related Study Guides

- [8.5 Community Ecology](/ap-bio/unit-8/community-ecology/study-guide/GhiVt7Egu8crmrHtQXXc)

## Review

### Related Terms

- Food Chain: A linear sequence of organisms through which nutrients and energy pass as one organism eats another.
- [Keystone Species](/ap-bio/key-terms/keystone-species): A species that has a disproportionately large effect on its environment relative to its abundance.
- Biomagnification: The process by which the concentration of toxic substances increases in each successive link in the food chain.