While the eyes, ears and tails of your dog may get most of the attention for their expressiveness, don't underestimate the power of paws! Aside from just being awfully sweet, the paws are wonderfully designed appendages that enable canines to perform their feats of doggie derring-do. Whether slender and elegant, bold and athletic, or floppy and furry, a dog's trotters are a fascinating study in anatomy and adaptation.
Consider the following:
Anatomy of the Paw
1. Of the 319 bones, on average, that comprise a dog's skeleton, a handful of those (so to speak) are dedicated to the paws. Along with bones, dog feet include skin, tendons, ligaments, blood supply and connective tissue.
2. Paws are made up of the following five components:
3. The digital and metacarpal pads work as shock absorbers and help protect the bones and joints in the foot. The carpal pads work like brakes, of sorts, and help the dog navigate slippery or steep slopes.
4. Paw pads have a thick layer of fatty tissue that insulates the inner foot tissues from extreme temperatures, as it doesn't conduct cold as quickly. (Think whales and blubber.) Meanwhile, as the paw gets cold when it hits the ground, arteries transfer the chilled blood back to the body where it warms up again. Because of these traits, scientists believe that domestic dogs first evolved in colder environments before spreading out into other climates.
5. The pads also offer protection when walking on rough terrain. Dogs that are outside a lot and exposed to rough surfaces have thicker, rougher paw skin; dogs that stay in more and walk on smoother surfaces have softer pads. The pads also help the dog distinguish between different types of terrain.
6. The inner layer of skin on the paw has sweat glands that convey perspiration to the outer layer of skin, which helps cool a hot dog and keeps the pads from getting too dry. But paws can also exude moisture when a dog gets nervous or experiences stress; dogs get sweaty hands, just like we do!
7. Dogs are digitigrade animals, meaning that their digits — not their heels — take most of their weight when they walk. Because of this, dogs' toe bones are very important.
8. Dog's toes are equivalent to our fingers and toes, although they are unable to wiggle them with the ease that we do.
9. Dewclaws are thought to be vestiges of thumbs. (Imagine if dogs had evolved opposable thumbs? The world would be a very different place!) Dogs almost always have dewclaws on the front legs and occasionally on the back. Front dewclaws have bone and muscle in them, but in many breeds, the back dewclaws have little of either. (Because of this, dewclaws are often removed to prevent them from getting snagged. However, opinions on the necessity of this procedure are mixed.)
10. Although they don't provide much function for traction and digging, dogs do use their dewclaws; for example, they help the dog get a better grip on bones and other things the dog may like to chew on.
11. That said, Great Pyrenees still use their rear dewclaws for stability on rough, uneven terrain and often have double dewclaws on the hind legs. Among show dogs, the Beauceron breed standard is for double rear dewclaws; the Pyrenean shepherd, briard and Spanish mastiff are other breeds that have double rear dewclaws listed for show standards as well.
Shape and Size
12. Breeds from cold climes, like St. Bernards and Newfoundlands, have wonderfully large paws with greater surface areas. Their big, floppy paws are no accident; they help them better tread on snow and ice.
13. Newfoundlands have the longest toes of all breeds, and Labrador retrievers come in second. Both breeds also have webbed feet, which helps make them excellent swimmers. Other breeds with webbed feet include the Chesapeake Bay retriever, Portuguese water dog, field Spaniel and German wirehaired pointer.
14. Some breeds have what are called "cat feet." These have a short third digital bone, resulting in a compact feline-like foot; this design uses less energy to lift and increases the dog's endurance. You can tell by the dog's paw print: cat feet prints are round and compact. Akita, Doberman pinscher, giant schnauzer, kuvasz, Newfoundland, Airedale terrier, bull terrier, keeshond, Finnish spitz, and old English sheepdog all have cat feet. (But don't tell them that.)
The elegant hare feet of the greyhound are responsible for the spring in their step. (Photo: Marianne Perdomo/Flickr)
15. On the other hand — er, paw — some breeds have "hare feet," which are elongated with the two middle toes longer than the outer toes. Breeds that enjoy hare feet include some toy breeds, as well as the Samoyed, Bedlington terrier, Skye terrier, borzoi and greyhound. Their paw prints are more slender and elongated.
16. And then there's "Frito feet." If you notice the distinct smell of corn chips emanating from the feet of your dog, resist salivating. Because when you find out that the source of the aroma is due to bacteria and fungi, you may become mightily grossed out. Generally this doesn't lead to complications for the dog.
17. Do you love having your hands massaged? So does your pup! According to the ASPCA, a paw massage will relax your dog and promote better circulation. They recommend rubbing between the pads on the bottom of the paw, and then rubbing between each toe.
18. Although the exact etymology isn't known for sure, the word "paw" appears to come from the Gallo-Roman root form "pauta," which is related to late 14th century Old French "patin," which means clog, as in the type of shoe. And with that in mind, we leave you with the following photo of a pup in boots (which we're guessing he jumped out of immediately after the picture was taken):