Yes, we humans adapt by using our heads --we have even surpassed the knowledge of making tools to hunt meat, and learned how to split the atom -- so that now we have the Nuclear Bomb!- aint that cool?.
Nevertheless, I feel you are missing MH's point regarding Early Early Early mankind- Man in his simple origins- before he adapted and learned how to compensate to get what he desired.
MH shares his knowledge from what he also has learned from others from the past. He in no way claims to have all the answers. In many posts you'll notice him encouraging others to research what they can for themselves and not take his word for it. MH doesnt pretend to be a medical doctor.