1 in 8 bird species threatened with extinction world wide.

[The_Squid]

The straw hut would be equated to a birds nest in my view. SO yeah kind of natural.

Did you cut the grass for your hut with a blade? Then it isn't natural. Did you burn down a forest to put in a village of these grass huts? Human activity is not natural by definition.

If it occurs in nature then it is natural.

Basically, at what point in time did human activity stop being natural?

The painting on the cave wall is not natural.

Using fire to cook is not natural.

I don't know where on the timeline of human evolution we stopped being part of nature, but it is probably measured in hundreds of thousands or millions of years.

Using a club to kill dinner is probably natural. Using a stone to sharpen the club into a spear to stab dinner to death is not.

[Guest American Woman]

OK thanks. How about living in a cave with a painting on the wall, is that natural?

Is using fire to cook natural?

Basically, at what point in time did human activity stop being natural?

A big reason why animal behavior and human behavior is different is that animal behavior is instinct, hence "natural," while human behavior is thought out and deliberate; ie: based on choices.