Dogs may be man's best friend now -- but the fox may have been his first boon companion.

Archaeologists digging in Jordan may have shed new light on human-animal relationships, with the discovery of a fox buried beside a human about 16,500 years ago -- some 4,000 years before the earliest known human-dog burial.

Led by researchers from the University of Cambridge, the group claim that their findings indicates a time when foxes were kept as pets, in this case one buried beside his master to accompany him to the afterlife.

"The burial site provides intriguing evidence of a relationship between humans and foxes, which predates any comparable example of animal domestication," said Dr. Lisa Maher from the Leverhulme Centre for Human Evolutionary Studies, University of Cambridge.

"What we appear to have found is a case where a fox was killed and buried with its owner. Later, the grave was reopened for some reason and the human's body was moved. But because the link between the fox and human had been significant, the fox was moved as well, so that the person, or people, would still be accompanied by it in the afterlife," Maher said.

The research focused on the contents of two particular graves at Uyun-al-Hammam, situated on an ancient river terrace in the small river valley of Wadi Ziqlab in Jordan. The site has been one of major interest for archaeologists since the first graves were opened in 2005, providing a rich source of information about the so-called early Epipalaeolithic period, 16,500 years ago.

The relationship between men and fox was probably short-lived, the researchers wrote in online science journal PLoS One. The paper also says it is unlikely that foxes were ever domesticated in full, and despite their early head start, their recruitment as a friendly household pet fell by the wayside in later millennia as their human masters took to the more companionable dog instead.