Notorious for raiding bins and preying on pets, foxes are widely considered a nuisance.

But they used to be man's best friend, according to a study. Researchers analysed remains found at an ancient burial site in Patagonia, Argentina dating back to 450AD.

While it contained the skeletons of 18 adults and six children, there was also evidence that an ancient fox species was buried alongside the humans.

Analysis revealed foxes were buried in the same graves, and had shared a similar diet to humans, indicating a close relationship.

The species of fox discovered - Dusicyon avus - was roughly the size of a German shepherd but is now extinct.

Notorious for raiding bins and preying on pets, foxes are widely considered a nuisance (Stock image)

But, according to a study, they once used to be man's best friend (Stock image)

The researchers, which included scientists from the University of Oxford, suggest the fox was potentially a companion pet for hunter-gatherers.

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However, they believe the introduction of the modern dog led to their decline as companion animals.

The study, published in the journal Royal Society Open Science, reads: 'The co-burial of humans and foxes is a rare archaeological record worldwide, and suggests a cultural or symbolic significance.

'Although the reasons for its inclusion in a mortuary context remain unclear, the most plausible explanation is that this fox was a valuable companion to the hunter-gatherer groups.

'Its strong bond with human individuals during its life would have been the primary factor for its placement as a grave good after the death of its owners or the people with whom it interacted.'