Comments by "Bo McGillacutty" (@Mrbfgray) on "Brazil's drought exposes ancient rock engravings on banks of Amazon River" video.

@darthheisenberg5983 There almost certainly were, they were in N. America well before 20k yrs ago and possibly WAY before that. White Sands footprints prove over 20k yrs.
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@voidisyinyangvoidisyinyang885 Depending on where on the river this is, ocean levels may or not have effected river levels. Since this lower level isn't about sea level dropping it's a good bet sea level isn't effecting it much.
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