There seem to be few species that work so well together as dogs and homo-sapiens. There are some symbiotic species, where one requires the other to survive, but nothing quiet like the dog/human relationship...maybe the clown fish and sea anomie.
We have archeological evidence for the comradeship dating back about 14000 years. This is a dog burial in Germany, where one was laid to rest with a human. Another, just a dog burial, lies in the wilds of North America at about 11000 years. So speculation places dog/human interaction at about 35000 years ago. This will probably be moved back as the archeological record is never complete and always adjusting itself as new finds are discovered.
Homo-Sapiens have been be-bopping about for about a quarter of a million years, it seems hard to believe that at some point in that long journey some hairy dude was sitting on a rock gnawing on a rabbit leg, looking at a smattering of wild dogs and resisted the urge to toss the dog a bone.
But whoever did that, whenever they did it. Thank you!