Interrelationships between predators in the animal kingdom are little known and difficult to study, but a researcher at the University of Tennessee in Knoxville has discovered that adversity created by an inhospitable environment can lead to the development of unexpected friendships among wolves and hyenas.

Typically, neither hyenas nor wolves are receptive to other species of carnivore. Hyenas often have vicious fights with both lions and African wild dogs, and steal kills that leopards and cheetahs have made. They will also kill domestic dogs of any stature. In turn, wolves sometimes hunt and kill coyotes and even dogs, their closest relatives.

Vladimir Dinets, an assistant professor of psychology at UT, has explored the unexpected friendship created between grey wolves (Canis lupus) and striped hyenas (Hyaena hyaena) in the southern Negev, Israel. His findings have revealed that the particularly barren conditions of the extreme desert might have led the two traditional enemies to forge an unusual alliance, primarily in terms of the need for food. The results of Dinets' research have recently been published in a study co-authored with the Israel-based zoologist Beniamin Eligulashvili.

In explaining the interrelationship between the two predators, Dinets said, "Animal behavior is often more flexible than described in textbooks." He highlighted the fact that humans can also learn from the hyena-wolf partnership, saying: "When necessary, animals can abandon their usual strategies and learn something completely new and unexpected. It's a very useful skill for people, too."

Still, Dinets and Eligulashvili were surprised to observe striped hyenas, which are the lesser-known, largely solitary relatives of the notorious spotted hyenas of Africa, in the midst of packs of grey wolves, migrating together through a series of canyons in the southern areas of the Negev desert.

At first, the research duo noticed this phenomenon by taking note of animal tracks. Four years later, they saw it happening directly. They do not know whether it was the same animals in both cases, and determining if it is abnormal behavior or something that occurs frequently but has never been recorded also remains to be seen.

The researchers have a theory: both predators might accept each other due to the mutual benefits that they gain from roving the tough terrain of the desert together. On one hand, wolves tend to be more agile and are capable of hunting down all large animals through the region, while on the other the hyenas have an especially keen sense of smell and are able to nose out carrion from miles away.

The grey wolf and the striped hyena can be found living in many different geographic regions, and their habitats interlace across several parts of Asia. The southern Negev desert is the most arid location where the two species are known to coexist.

The research report was published in the journal Zoology in the Middle East.