Recently Gongora et al. (1) stated that their analyses of chicken mtDNA and potential offsets for dietary marine carbon cast doubt on “claims for pre-Columbian chickens” in the Americas. We present additional data supporting the interpretation of Storey et al. (2) showing that evidence for pre-Columbian chickens at the site of El Arenal, Chile, is secure.
Gongora et al. (1) analyzed mtDNA of modern chickens only. They gave no consideration to the fact that both European and prehistoric Pacific chickens are ultimately Asian-derived and thus may be expected to share lineages. European stocks were further influenced by the 19th-century import of Chinese chickens to develop commercial and show breeds (3). The authors also imply that the Indian/Asian/European mtDNA signature identified in our ancient Pacific and Chilean samples would not have been available for dispersal to the prehistoric Pacific. This is refuted by linguistic, archaeological, and ethnohistoric evidence (4).
Ultimately, the question rests on the antiquity of the El Arenal chickens. We have directly dated and sequenced two additional chicken bones from the site, which is not a shell midden as claimed (1). Stable isotope determinations (δ 13C, δ 15N, and δ 34S) further confirm a terrestrial dietary signature; thus, no marine calibration of the dates is required (Table 1). All dates obtained from the site are securely pre-Columbian (even at 2σ), consistent with the stratigraphic and artifactual evidence. Therefore, the most parsimonious explanation continues to be that chickens were first introduced to South America by Polynesian voyagers as part of a well-documented eastward expansion.
Table 1.
Radiocarbon and isotope data for archaeological chicken bones and associated thermoluminescence dates obtained from pottery from the El Arenal-1 site in Chile
| Sample no. | Lab no. | Material | Date | Calibrated age (2σ) | δ 13C, ‰ | δ 15N, ‰ | δ 34S, ‰ | P, Gy | D, Gy/year |
|---|---|---|---|---|---|---|---|---|---|
| CHLARA001 | NZA 26115 | Chicken bone | 622 ± 35 BP | AD 1304–1424 | −20.9 | ND | ND | ||
| CHLARA003 | NZA 28271 | Chicken bone | 510 ± 30 BP | AD 1427–1459 | −19.85 | 2.6 | 2.16 | ||
| CHLARA004 | NZA 28272 | Chicken bone | 506 ± 30 BP | AD 1426–1457 | −19.45 | 3.5 | ND | ||
| EA1-001 | UCTL 1617 | Pottery | 650 ± 65 BP | AD 1285–1415 | 1.14 ± 0.11 | 1.76 × 10−3 | |||
| EA1-002 | UCTL 1618 | Pottery | 610 ± 55 BP | AD 1335–1445 | 0.96 ± 0.11 | 1.58 × 10−3 |
Footnotes
The authors declare no conflict of interest.
References
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