surely everything that Humanity, a mere animal of Nature, does is natural

It was the hallmark of the non-God-fearing members of Panic Modernity (1865-1965) to believe that (a) 'Man' was but an animal of Nature and yet (b) almost everything that 'Man' did was not natural.

Even while the God-fearing members of that era persisted in believing that humanity were not mere animals, they were at least consistent in also denying that anything humanity did was 'natural a la Nature'.

So, back to the no-God-fearers : to them, if the beaver-the-animal built a big lodge for its family that was natural ---- but if humanity-the-animal built a big lodge for its elderly members that was un-natural.

And humanity putting its elderly in comfy lodges was not natural but humanity putting its elderly at the chilly edge of the snowy woods was natural.