Originally Posted by dyna mo

But that is technology





And that's one of the debates re: Hansen's list. An Asteroid is a technological tool and the assumption is that Tool using animals also require big brains. That's based on earth biology, perhaps it is too big an assumption but I believe it valid assumption.

but I'm all for correcting the assumptions, but I think the list is pretty solid, especially when we take into account that we CLEARLY have not been colonized or even communicated to/with from ETs.

Let's assume your idea happens to be true, a microbe figures out how to hitch a ride on an asteroid. then the premise is they are intelligent enough to realize the value and need to colonize, that's why they caught that ride. That level of intelligence also is highly capable of communication, and other things.