Originally Posted by
Sutekh
Good question, but...
Spoiler: for the engineers to be SO similar to us, despite their planet being god knows how far away & chemically composed of who knows etc, they turn out 2 hands, 2 eyes, even eyeballs with pupils etc - to a biologist, for something so similar to exist without god or panspermia involved is seriously improbable. The fact they have better tech and the evidence of previous visits to earth, along with the way the bio weapons seem tailored to attack humanoids, logically suggests they are our progenitors
This way, the original films make more sense - the facehuggers etc seemed so tailored to human anatomy that it beggared belief somewhat to suggest they would be found in some back o beyond that humans had never visited