They look alike because they are alike.
In fact, they are the same.
What some see as "primates", are probably those who died with bone disfigurements.
I believe if King David's bones were dug up today -- (assuming they were fossilized) -- he would look like either a Cro-magnon or Neanderthal.
If you read the 38th Psalm, you'll see that he died of a strange disease that changed his physical appearance dramatically.
Notice especially verse 6:
Psalm 38:6 I am troubled; I am bowed down greatly; I go mourning all the day long.