Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025
Definition
Crocodilia is an order of large, predatory, semi-aquatic reptiles that includes crocodiles, alligators, caimans, and gharials. They are characterized by a long flattened snout, powerful jaws, and a robust body covered in thick scales.
Crocodilia are found primarily in tropical and subtropical regions around the world.
They possess a four-chambered heart similar to birds and mammals, which is unique among reptiles.
Crocodilians have specialized sensory organs called integumentary sense organs (ISOs) on their skin that detect changes in water pressure and vibrations.
Their reproduction involves laying eggs with hard shells; females often guard nests and may assist hatchlings to water.
They exhibit temperature-dependent sex determination (TSD), where the temperature of the nest determines the sex of the offspring.
A class of cold-blooded vertebrates that includes snakes, lizards, turtles, and crocodilians
Temperature-Dependent Sex Determination (TSD): A type of environmental sex determination where the temperatures experienced during embryonic development determine the sex of the offspring
Integumentary Sense Organs (ISOs): Specialized sensory receptors found in crocodilians that detect physical changes in their environment