[SunkenCiv]

There’s a range of opinion of course, of course.

There’s a very small amount of scientifically dated remains of humans and animals from North American (and S A and the Caribbean for that matter) that antedate 1492.

Artifacts and petroglyphs related to horses have mostly not been scientifically dated (and thanks to NAGPRA etc, probably never will be), and oral traditions are, uh, fluid and not generally trustworthy, irrespective of their geographical and ethnic source.

Anyway, here’s one take on the “we had horses before Columbus” view:

https://ictnews.org/news/yes-world-there-were-horses-in-native-culture-before-the-settlers-came

[SunkenCiv]

Most of the "cactus hill" keyword:

• Who Were the First Americans? [01/13/2002]
• Immigrants From The Other Side (Clovis Is Solutrean?) [11/02/2003]
• When Did Humans Come to the Americas? [01/27/2013]
• Teams digging into history of the earliest people [07/25/2015]
• Rethinking the First Americans [05/19/2019]

[Varda]

NAGPRA has nothing to do with DNA analysis of animals or geologic analysis. There's plenty of DNA of various animals the Indians had. The horses are clearly related to Spanish horses. I agree the oral traditions are untrustworthy. That web site links to a page with a woman who looks about as Indian as Elizabeth Warren.

Link to the paper: Early dispersal of domestic horses into the Great Plains and northern Rockies