What is known of the religion/mythology/legends of the Polynesians who migrated into Oceania?

Question

I've been listening to a couple of Patrick Wyman's Tides of History podcast episodes about the archaeological, linguistic and genetic evidence on migration across Oceania by Austronesian speaking people around 4-3kya. One thing I've long wondered about which he doesn't touch on (perhaps because little or nothing is known) is the mythology that led family groups to undertake voyages that, I assume, most did not survive. Heading out on 1000 km voyages across open ocean carrying all your water (& food?) without knowing what's over the horizon seems likely to end badly for all but a rare lucky few.

The descendants of a group that did make it would, however - one imagines - maintain a tradition that glorified what their ancestors had done, leading to elevation of the idea in later generations. Is anything known about these stories & the legends they became?

ETA: Found some interesting discussion here about "founder ideology" though it's pretty speculative.

Answer 1

If I'd been more patient I would have heard a partial answer in this week's ToH podcast episode, an interview with prof. Vinson Kirch (U of Hawaii & UC Berkeley) Spotify link. Patrick put more or less this question to him, and he answers in part with the oral tradition from Rapa Nui, that the island was settled by a chief (possibly from the Marquesas) who sent out a cohort of young men to find an island that he'd seen in a dream. One group of them came back having found Rapa Nui and left behind a plot of yam seedlings. At that point they assembled the larger double-hulled canoes & set out as a family group for the new land. So it's not - in that instance - whole families heading out into the unknown, but instead a bunch of exploratory missions - presumably not all of which return.

He mentioned both the pull of becoming a "founder" (due to Polynesian traditions of birth order rank in social hierarchy across multiple generations) and the push of population pressure and conflict. He also mentions the idea that they thought there was land in all directions, which of course had worked for their ancestors. It wasn't clear (to me) how well attested that idea is.