What animal stays with its mate forever?

Beavers are one of the few mammals that mate for a lifetime, only choosing to find another mate if their original mate dies. But here's where it gets interesting: there are two types of beavers, European beavers and North American beavers.

Even birds famously reported to “mate for life” - swans, geese, vultures, penguins and albatrosses – quickly find a new mate if one of a pair perishes. In mammals, only 3% of 4,000 mammal species are reported to be monogamous. Most-often cited: beavers, wolves, Gibbons and Prairie voles.

Gray Wolves are monogamous, often mating for life. In the pack, only the alpha pair has sexual rights during breeding season. Females are normally sexually mature at 2-years of age. Males are sexually mature at 2- to 3-years of age.

Loyalty/teamwork. Wolves are fiercely loyal to their pack, they are the ultimate team players. Many sports teams, families and businesses could learn a thing or two from the teamwork that wolves demonstrate. Understand your place, follow the rules and be loyal to your 'pack'.

1. Akita. Topping the list of the most loyal dog is the Akita which are described by the American Kennel Club as being "profoundly loyal". One famous Japanese Akita, called Hachiko, continued to wait at a train station every day for 10 years after his owner's death, hoping he'd eventually return home.

Elephants

Elephants may be the most protective moms on the planet. Herds of females and children usually travel together in a circle with the youngest member on the inside, protected from predators. If one child becomes an orphan, the rest of the herd will adopt him. Elephants also mourn their dead.

For years, wolves and dogs were considered separate species: canis familiaris and canis lupus. However, more recently, scientists generally agree they are both a sub-species of canis lupus. Unlike dogs and foxes, wolves and dogs can reproduce, creating the controversial wolf-dog.

Wolves that are raised as domestic animals are friendly to humans and other animals and exhibit dog-like behaviors, while wild wolves are afraid of humans and can be hostile when they encounter humans. Many people want to own wolves as pets, although that is not possible for every pet owner.

He thought their remarkable diversity must reflect interbreeding with several types of wild dogs. But the DNA findings say differently. All modern dogs are descendants of wolves, though this domestication may have happened twice, producing groups of dogs descended from two unique common ancestors.

Wolves and dogs are interfertile, meaning they can breed and produce viable offspring. In other words, wolves can interbreed with dogs, and their offspring are capable of producing offspring themselves.

Short answer: no, they can't. They simply don't have compatible parts. (Of course, that doesn't mean they can't be friends: witness Juniper the Fox and Moose the Dog, above). The longer answer to why dog-fox hybrids can't exist has to do with the two species having vastly different numbers of chromosomes.

Cats and dogs cannot mate with each other, even if it looks like they're trying to do so. Their breeding behaviors, heat cycles, and different DNA prevent them from being able to produce healthy, viable offspring. Hybrid species can be created when the animals have similar DNA to each other, such as lions and tigers.

Foxes are a part of the Canidae family of animals, which makes them canines. They are closely related to domestic dogs and wolves. The canine family also includes coyotes, jackals, and even raccoons! Canines, also called canids, are characterized by their slender build, long legs, bushy tails, and long muzzles.

A coydog is a canid hybrid resulting from a mating between a male coyote and a female dog. Hybrids of both sexes are fertile and can be successfully bred through four generations. Similarly, a dogote is a hybrid with a dog father and a coyote mother.

No dogs here! Hyenas are not members of the dog or cat families. Instead, they are so unique that they have a family all their own, Hyaenidae. There are four members of the Hyaenidae family: the striped hyena, the “giggly” spotted hyena, the brown hyena, and the aardwolf (it's a hyena, not a wolf).

As mentioned, it's illegal to keep true wolves as pets in America. However, a wolf must be more than 98% pure to count as a wolf, which leaves a lot of room for hybrid animals under federal law. That doesn't mean you can go out and get a wolf-dog today as a pet.