Also the story of the snake giving us knowledge fits the story of prometheus, who brought humans fire and was punished for it, quetzacoatl is also bringer of knowledge while being venus or lucifer, satan before its fall.
Pic related. My theory it depicts knowledge, as those people are the keeper of knowledge, or bringer of that.
The mayan/aztec one seems to depicts quetzacoatl I assume which is said to have brought that for the aztecs.
Göbekli tepe apparently talks about a comet bringing civilization.
http://www.telegraph.co.uk/science/2017/04/21/ancient-stone-carvings-confirm-comet-struck-earth-10950bc-wiping/fitting the alignment of angkor wat and the pyramids of 12,5k years ago, as well as the comet that struck earth 12,9k years ago
In case of the sumerian i suppose it is enki
https://en.wikipedia.org/wiki/Enki>Enki (/ˈɛŋki/; Sumerian: dEN.KI(G)𒂗𒆠) is the ancient Sumerian god of water, knowledge (gestú, literally "ear"), mischief, crafts (gašam), and creation (Nudimmud: nu, likeness, dim mud, make beer)Same role Quetzacoatl took, bringing knowledge, or Satan with the apple. Prometheus who brought the fire very well could be the same enthity, Lucifer. The Kabba in Mecca supposedly contains a meteorite, which might be the one Göbekli Tepe speaks of or Satan that was thrown to earth
but i assume there is more to it
Now the FALLEN angels are said to have brought the knowledge for witchcraft and warcraft. Ironsmithing is one of these skills used for warcraft. Turns out the ancient egyptians used iron used from meteorites aka FALLEN rocks in example for this dagger
https://en.wikipedia.org/wiki/Tutankhamun%27s_meteoric_iron_dagger_blade 