Have you ever heard the sound of a dog's paws clicking on a tiled floor? That distinctive "click, click, click" comes from their claws making contact. In contrast, cats can walk silently. What’s the secret? Cats have the ability to retract their claws.
But why do cats have retractable claws while dogs do not? The answer lies in their daily activities and hunting strategies.
Differences in Claw Function
According to evolutionary biologist Anthony Russell from the University of Calgary, cats primarily use their claws for capturing and gripping prey. Their front claws are for gripping, while the back claws help in tearing into the prey. Thus, cats need to keep their claws sharp for effective hunting.
"Claws that are always extended would wear down from friction with the ground, similar to how humans file their nails," Russell explains. Therefore, a cat's claws are naturally retracted to maintain their sharpness. They only extend them when necessary and retract them for future use.
In contrast, dogs are social hunters that chase prey over long distances until it tires out before attacking as a pack. "When wild dogs hunt, they can run for miles, nipping at the prey until it is exhausted, then the whole pack pounces," Russell adds.
Because they hunt in groups, dogs do not need to grip their prey as tightly, so their claws do not need to be as sharp as a cat's. Their advantage lies in their numbers and stamina.
While not as sharp, dog claws still serve important functions, particularly in providing traction and maneuverability while running. Xiaoming Wang, a paleontologist at the Natural History Museum of Los Angeles County, explains that dog claws help them grip the ground and change direction quickly while chasing prey.
Most cats can run without using their claws, but cheetahs are an exception. "Cheetahs run too fast to avoid using their claws for grip and traction," Wang notes.
Consequently, cheetah claws have evolved to be less retractable, resembling dog claws, to maintain high speeds during hunts.
In general, all carnivores have some ability to retract their claws. However, cat claws are "hyper-retractable," meaning they can be fully pulled back into the paw with little effort.
On the other hand, dog claws are more about enhancing grip while running, aiding them in long-distance hunts. Thus, both cats and dogs have claws adapted to their respective hunting strategies.