Population Y revisited: found on the Pacific coast and in ancient Brazilian shell mounds, still contested (2021–2023)
Record: the document says itPattern: documents line upLens: our readingOpen: not yet provenDisputed: argued, often by a hostile witness
Year: 2021 · Places: South America
SUMMARYPopulation Y revisited: found on the Pacific coast and in ancient Brazilian shell mounds, still contested (2021–2023) [Connections: Genetics (honest), Nov 5, 2026]
RECORDCastro e Silva, Ferraz, Bortolini, Comas and Hünemeier, "Deep genetic affinity between coastal Pacific and Amazonian natives evidenced by Australasian ancestry," PNAS 118(14) (2021): the signal also appears in the Pacific coastal Chotuna (Mochica descendants), Guaraní Kaiowá and Xavánte; it was lost in Karitiana, Suruí and Guaraní Kaiowá when only unrelated individuals were tested; the authors call it still controversial and sensitive to sample choice, and propose it entered by a Pacific coastal route, which could explain its "absence" in the Central and North American populations studied. Ferraz et al., Nature Ecology & Evolution 7:1315–1330 (2023): genome-wide data from 34 ancient Brazilians, some at Jabuticabeira II and Cabeçuda shell mounds (sambaquis), show signals linked to Population Y
PATTERNthe signal is now seen in ancient bones, so it is not just a modern artifact, but its size and spread shift with which people are sampled. That is the Rule 14 problem in reverse: the sample decides the story
LENS (WW9)the shell-mound builders of Brazil carry it; the mound builders of the Southeast have not been asked
DISPUTEDstrength and distribution of the signal
OPENno test of Southeastern ancient or living people for this signal found
SOURCECastro e Silva et al. 2021 (PMC8040822); Ferraz et al. 2023, Nature Ecology & Evolution.