Alligators and Crocodiles have bony protective scales called “scutes.” These scales are different from typical reptile scales because they are so wide and bony.
The scales of crocodiles and alligators are not fused with the skeleton, giving the crocodile better flexibility. Each scute is a separate material, with several layers below it. While some patterns repeat themselves, no two crocodiles have the same scute patterns.
What Are Crocodile Scales For?
The main function of crocodile scales is to prevent water loss. The scutes are largest at the back because it is the part that receives the most exposure under the sun. Its thickness prevents the risk of drying out.
Crocodiles and alligators have their backs exposed to the sun all day long. They evolved to protect that part of their body, and it is why they have back armor.
The areas with the least scutes are around the shoulders and hips, because the crocodile needs better flexibility around these areas. The belly also has thin scales, making it a vulnerable part of the animal.
Are Alligator and Crocodile Scales Sensitive?
Crocodile and alligator scutes are sensitive to touch. These scales are not just armor, but they also have nerves endings that can transmit a signal to the brain.
The scutes of crocodiles and alligators make for excellent body armor, but they also rest on nerve endings that the animal can use to sense its surroundings.
Each crocodile has thousands of scales, and each scale has a nerve ending. It is widely believed in the scientific community that these nerve endings begin to develop before they even hatch.
These nerve endings start to develop from the head, but as the animal matures, the nerve endings grow down to the crocodile’s body to the end of the tail.
These nerves are not just capable of sensing touch, but they can also “feel” temperature and even determine pH levels. This means that the crocodile’s scutes function almost like skin. It can feel the temperature, which tells the crocodile when it is time to bask under the sun or go back in the water.
What Are Crocodile and Alligator Scutes For?
Crocodiles and alligators use their scutes for hunting. Scutes are so sensitive because of the nerve endings under them that an alligator can use their scutes to detect tiny ripples in the water.
In many TV shows, animal channels often show crocodiles hunting in the day. The truth is they prefer hunting at night when it is dark.
Unlike some snakes, crocodiles do not have a heat-sensing vision. Instead, they use the sensitivity of their scutes to detect movement. These scutes can feel a tiny ripple underwater if an animal on land is drinking from it.
When a crocodile detects this movement, it can sneak up to the prey, and it does not even need to see the prey. Alligators and caimans only have these nerve spots around their faces, but crocodiles have them around their bodies.
Are Crocodile Scales Bulletproof?
No, crocodile skin or scale is not bulletproof. It is thick, but bullets can penetrate it. Crocodile skin is one of the toughest leathers out there, and it is why it is highly sought after.
The toughness of the scale varies from one area to another. The scutes from the back of the animal are the toughest, while those from the belly are the softest. The belly scales are similar to those of a snake.
Scutes from a crocodile’s back are as hard as a bone because they contain osteoderms. These are small bone deposits that make the scales almost impenetrable. Despite their toughness, even these scales are not bulletproof.
People who hunt crocodiles hunt with guns. Sometimes, the bullet may bounce. It happens when the shot is made from an angle. As such, it’s a common myth that croc scales are bulletproof.
How Big are Crocodile Scales?
Crocodile scales can grow up to five inches in width, depending on the age of the crocodile. Once a crocodile matures to 15 years, its growth rate slows down.
After around 15 years, crocodiles growth rate slows, although their scales continue to grow slowly. Crocodiles can reach a hundred years old, so the scutes have a long time to develop.
What are the Dark Spots on Alligator Scales?
Intergumentary Sensory Organs are small, dark spots found on an alligator’s face and mouth. A study published in the Journal of Experimental Biology explains that these spots contain lots of nerve endings and help the alligator with hunting and sensing their environments.
These touch sensors feel not only temperature and pH levels but also vibration, including the touch of human fingertips.
Integumentary sensor organs or ISOs are used for:
- Provision of oily secretions
- Detection of electric fields
- Detection of water salinity
- Detection of pressure and vibrations
Back in 2002, a biologist noted that alligators in a darkened aquarium responded to droplets of water. It happened despite the presence of other noises in the water. The alligators, upon hearing the droplet, turned to face the droplet’s location.
The conclusion was that the sensor in the alligator’s face is also a mechanism to detect vibration, even from a single drop. The biologist also found out that the spots are connected to the brain.
The study revealed a diverse collection of mechanoreceptors in these spots. These nerves respond to pressure. They also respond to vibrations within the 20 and 35 Hertz range. Some respond to the pressure that a human finger cannot detect.
Summary: Do Alligators and Crocodiles Have Scales?
Crocodiles have scales, and these scales are called scutes. The thickness of the scute varies from one area of the body to another, the thickest of which is at the back.
The scutes have nerve endings, which makes them sensitive to touch. It can also detect temperature and pH levels in the water. A crocodile’s scute is not bulletproof, but it can be thick like a bone because it has osteoderms.
Stuart is the editor of Fauna Facts. He edits our writers’ work as well as contributing his own content. Stuart is passionate about sustainable farming and animal welfare and has written extensively on cows and geese for the site.