🧬ap biology review

Dinosaurs

Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examWritten by the Fiveable Content Team • Last updated September 2025

Definition

Dinosaurs are a group of reptiles that appeared during the Mesozoic Era, between 230 and 65 million years ago. They are characterized by their upright stance, with legs located directly beneath the body.

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