Longevity in domestic dogs depends on the care they receive, their breed, and body size. In general, larger breeds have shorter life spans.

Many giant dog breeds average only 7 or 8 years, while some small terrier breeds might live as long as 20 years.

The average lifespan for mixed-breed and midsize dogs is about 13 to 14 years. The longest-lived dog with reliable documentation died at 29 in 1939.

There are 701 types of pure breed dogs.

A dog's sense of smell is about 1000 times better than a person's