The linked article doesn't say anything about native Americans, and in terms of substantive data it seems to jump in history from the 4th century prevalence of

The linked article doesn't say anything about native Americans, and in terms of substantive data it seems to jump in history from the 4th century prevalence of Roman bathhouses, to 16th century local bans on swimming, filling in the gaps (which account for the entire premise of the article) with speculation about bridges and mermaids. It immediately follows the description of those swimming bans with other 16th century examples of Tudor scholars endorsing and writing guides on swimming, resulting in an article that's an interesting read but with a poorly supported thesis.