Meanings of spend millennia in English

Many of our rarer plants and animals have spent millennia evolving to cope with shifting sands.

I could have spent millennia like that, days and nights walking the earth, sating my senses.

I have spent millennia mastering love.

After all, Europe has spent millennia deforesting its lands and is one of the major historical culprits behind climate change.

Dwarfs have spent millennia escaping from cave-ins, and they have developed the ability to squeeze through tighter holes than this one.

Scratch is perhaps less useful for learning algebra or metallurgy, which, unlike Scratch, are less brandable, having spent millennia in the public domain.