Dogs have dewclaws because they’re essentially a leftover “thumb” that still helps with gripping, balance, and fast movement, even though it doesn’t always touch the ground.

What dewclaws are

  • A dewclaw is an extra digit high on a dog’s leg, usually on the inside of the front legs, in roughly the same position as a human thumb.
  • In many dogs, front dewclaws are attached by bone and ligaments, while rear dewclaws (if present) are often attached only by skin.

Why dogs have dewclaws

  • Early dog ancestors used all their toes, including a thumb-like digit, for activities like climbing and gripping; as they evolved to run on their toes for speed, that digit shifted higher and became the dewclaw.
  • The name “dewclaw” likely comes from the idea that this high claw brushes dew off grass as the animal moves.

What dewclaws do today

  • Front dewclaws help dogs grip things like bones, toys, or chews between their paws while they hold and nibble.
  • When dogs run fast and make sharp turns, the dewclaws can touch the ground and act as extra traction, helping stabilize the wrist (carpus) and reducing strain on joints and even the spine.

Rear dewclaws and specific breeds

  • Some breeds, such as the Great Pyrenees, Briard, Beauceron, and Icelandic Sheepdog, often have double rear dewclaws that can even be part of the official breed standard.
  • In mountain and herding dogs, these rear dewclaws may help with braking and stability on steep or rocky terrain when they rush down hills or chase predators.

Do dogs really need dewclaws?

  • Many veterinarians now recommend keeping normal, healthy front dewclaws because they contribute to grip and joint stability, and removing them may increase stress on other structures over time.
  • Dewclaw removal is usually reserved for specific medical or safety reasons (like repeated injuries), and decisions should be made case by case with a vet.

TL;DR: Dogs have dewclaws as an evolutionary leftover thumb that still helps them grip objects, stabilize their wrists, and gain traction in fast turns or rough terrain, especially on the front legs.

Information gathered from public forums or data available on the internet and portrayed here.