The Anunnaki are a group of deities of the ancient Sumerians, Akkadians, Assyrians and Babylonians. They were probably giants and may be the same as the Nephilims, but were they aliens or the progeny of aliens? The Annunaki were also called "The Shining Ones" because of the brightness of their skin.
https://en.wikipedia.org/wiki/Anunnaki Ufologists speculate that these giants were the result of intercourse by aliens (aka angels) with human women which resulted in Nephilim, the fallen men banished from the Garden of Eden and/or killed by the Great Flood. The Nephilims were giants that were cruel to humans, even killing and eaten them, so they were purged in the great flood and deluge.
Methuselah and Noah were reported to be giants and of great age, but Noah was excluded from the purge.
Adam and Eve are now described as pre-Adamite and were probably Nephilims, so not the first homo sapiens.