I'd have to disagree with that almost entirely. Look at human cultures all around the world - yes, there are huge differences, obviously - but there are also constants, 'memes' if you will that have appeared spontaneously and independently. People are both competitive and cooperative to some degree; they tend to live (at least some of the time) in small communities based on blood relation (anything from the nuclear family to larger tribal units), they display friendliness towards people they know and hostility and politeness, in some ratio or other, to those they don't; concepts like marriage, religion, authority and some idea of law and punishment seem to be universal.
The idea that human beings are somehow blank slates onto which cultural values and norms are passively inscribed is ludicrous. After all, if that were the case, how would those cultures have arisen in the first place? They're all, to some degree or another, codifications or elaborations of instinctual behaviour: militaristic nationalism or the patriotism of football fans at an internation match have evolved or mutated from notions of tribal loyalty; the justice and prison systems stem largely from the desire to see retribution exacted on wrong-doers; churches and temples are the institutionalised custodians of the awe primitive man saw in the stars and oceans which gradually crystallised into organised religion. Bear in mind we were wandering around butt naked hunting animals with stone tools a blink-of-an-eye ago, in evolutionary terms - and that in the parts of the world where people still live like that, they nonetheless mourn their dead, tell stories and laugh at jokes just like we do.
No-one would deny that there's something inherently 'doggy' about a dog's behaviour, regardless of its breed and individual history: why should humans be any different?