People viewed dogs as their friends since ancient times. To such conclusion scientists from the UK in the study of a number of animal burials. One of the discoveries made in the area of lake Baikal. Both humans and dogs was sick one and the same parasitic disease (tapeworm). It speaks to the cohabitation of animal and man.
Apparently, people shared their food with the pet. In addition, the graves of the dogs were often near the graves of the owners. The finding suggests that ancient times, people with dogs were friends.
Previously, scientists in Japan have conducted an experiment in which he discovered the cause of the affection dogs to humans. A strong correlation is due to the hormone oxytocin, produced in large quantities in the animal body.