Hercules, I won't define something which is pretty much well known everywhere.
the missing biological link...
... what do you think it is?
No, I asked you the question. After your semi-clarification in post #20 that you are referring to transitional fossils, I take it that you consider there are gaps in the fossil record of human evolution?
So, where are the gaps according to you? There are numerous fossils representing the transition of homonids from the genus Australopithecus to Homo, covering about a dozen distinct species within those two genuses. I see no need to resort to alien genetic engineering to explain our evolution.