Many people wonder if dogs and hyenas are biologically related, often due to their similar appearances and shared predatory behaviors in the wild. However, despite some superficial resemblances, the biological relationship between dogs and hyenas is more distant than it might seem at first glance. Understanding their classification helps clarify why these animals, while both carnivores, are not closely related.
Unpacking the Carnivora Order
Both dogs and hyenas are classified within the order Carnivora, a diverse group of mammals primarily characterized by adaptations for a diet of meat. While sharing this broad classification, the Carnivora order is further divided into two major suborders: Caniformia, which includes “dog-like” carnivores, and Feliformia, comprising “cat-like” carnivores.
Dogs, including domestic dogs, wolves, foxes, and coyotes, belong to the family Canidae, which falls under the Caniformia suborder. This family is widely distributed across all continents except Antarctica. In contrast, hyenas are unique enough to have their own distinct family, Hyaenidae. This family includes four extant species: the spotted hyena, striped hyena, brown hyena, and the aardwolf. The Hyaenidae family is classified within the Feliformia suborder, placing them on the “cat-like” side of the carnivore family tree.
Similarities and Misconceptions
People often mistake hyenas for a type of wild dog due to various physical and behavioral similarities. Both animals possess upright ears, a somewhat sloping back, and frequently hunt or scavenge in groups. They are known for their powerful jaws and teeth, capable of crushing bone. Additionally, both dogs and hyenas exhibit social structures and engage in pack hunting or scavenging.
These resemblances, however, do not indicate a close genetic relationship. Instead, they are examples of convergent evolution. Convergent evolution occurs when unrelated species develop similar traits or adaptations because they face similar environmental pressures or occupy similar ecological niches. For instance, both hyenas and many canids evolved as cursorial hunters, meaning they are adapted for running long distances to pursue prey, and primarily use their teeth for catching prey rather than claws. This evolutionary path led to the development of comparable body plans and behaviors suited for their roles as predators and scavengers in open environments.
Distinct Evolutionary Paths
The evolutionary histories of dogs and hyenas show distinct lineages despite their shared membership in the Carnivora order. The major split between the Caniformia and Feliformia suborders occurred approximately 50 million years ago, separating the evolutionary paths of “dog-like” and “cat-like” carnivores. The Canidae family, which includes dogs, first appeared in North America during the Late Eocene period, over 30 million years ago. Domestic dogs are direct descendants of the gray wolf. Other close relatives of dogs include various species of foxes, coyotes, and jackals.
Conversely, the Hyaenidae family, to which hyenas belong, diverged around 30 million years ago. Molecular studies reveal that hyenas are more closely related to mongooses, civets, and meerkats than to any members of the dog family.
The aardwolf, a species of hyena, diverged from the other hyena lineages approximately 13.2 million years ago. The bone-cracking hyenas, which include the spotted, striped, and brown hyenas, branched more recently, around 6 million years ago. Their classification within the Feliformia suborder places them on the evolutionary branch shared with cats and their relatives, not with dogs.