According to Marquesa legend he popped up out of Chaos one day, married ATANUA and spawned the first humans.
Meanwhile, Tuamotu mythology claims he’s a Sky God with an embarrassing lack of knowledge about female anatomy. Having created a nice lady God called FA-AHOTU to be his wife, it didn’t occur to him that he’d missed out two important bits until their baby sons almost died of malnutrition. FA-AHOTU had no breasts.
ATEA had to suckle them himself, but despite this little mistake TAHU, RO-O and TANE survived and thrived. In fact TANE went on to be a top God — after hitting his dad with a thunderbolt causing early retirement.