Humans built the sydney opera house right? engineered it?
So logically something must have engineered us, we just have never seen it, but it does not mean it's not there.
Can you see bacteria? NO. It's still there though.
But we didn't put the resources on earth, we just moved them around a bit. We didn't make anything. We're no different then the wind blowing sand into ultimately random patterns. They're temporary and irrelevant.