Ghost pepper

Another turtle-takeaway is the Ghost Population of Sonora. This broke from other New World genomes 22700 BC (where C-14 takes the pre-Los-Alamos baseline, I assume Y2k for genetics). That is of course long before muh Clovis and, more to the point, before that split in North America we were calling "ANC-A" and "ANC-B" back in 2018. This pre-A/B split looks VERY basal. But on the other side it came after Melanesia. This particular split, then, happened in northeast Siberia or Beringia.

The ghost makes up 28% of a genome from Sierra Tarahumara. That's where Gary Jennings put the Rarámuri, basically the Masai of northern Mexico - speaking an Aztecan language (but not Nahua) as of AD 1500. They are famed runners. Today it has spread as far as Brasil, presumed-unmediated by Spaniards. Dunno about the Caribs.

Meanwhile I do not find Melanesia anywhere in these early Norteño samples.

One possibility is a pre-ANC-A/B set of settlers. Another possibility - on the If It Happens Now It Happened Then principle - is that they are like the Navajo-Apache, rolling in from the northwest after the fact, subsequently blending in with the locals over millennia. This is a common pattern as witness the Mexica themselves who remember (accurately) coming in from the northwestern deserts. Yes, the [Pipil] Nahua got only as far as post-Ilopango El Salvador. Before 3000 BC even the Chibcha were not farmers so in less position to block migrants.

If we're looking north, as we should, I don't know how prevalent this ghost, in the great Bonneville basin pre-AD-100. There must have been a stronger (actual) Native presence in what is now a vast desert, ideal for preserving remains.