By far the most popular narratives to aliens in common is that each species or races with much at least humanoid also trains claims or conceived.
For this purpose, there is no rational reason.
Why should aliens resemble us?
Well, one could postulate that only those varieties wanted to come here aliens who find there similar looking one, the rest have no interest in us.
That sounds to me also very naive. Why you should not care about intelligent or less intelligent people, the very different set up than yourself?
Where did all the ants and algae and fungal researchers here below?
It is, therefore, once again, very likely to act one founded on self-love as to stupidity from hubris projection. (more ...)