This, like much of the rest of your piece is opinion, not "information". Funny, you didn't seem to analyze the New Guinea study you cited. Apparently clinical depression is not a thing for these people who live the way that most generations of humans have, in a small, socially bonded, cooperative hunter/mostly gatherer society. We on the other hand live in a competitive, individualistic, socially disconnected way and nearly one in five of us DO suffer from that malady. HMMMM. Sounds more to me like we are not evolved to live in our current and oh so recent society, judging by the others who live in the type of society in which we evolved. Betcha they're happy too, at least by comparison. Maybe we are evolved to be healthy and happy while living in the way that was our only choice for the first 199,800 years. Food for thought;)