Prehistoric sunflower (Helianthus annuus L.) domestication in Mexico

Early remains of Helianthus annuus L. unearthed at the San Andres site in t he Gulf Coast region of Tabasco, Mexico, constitute the earliest record of domesticated sunflower. Accelerator mass spectrometry (AMS) age determinati ons of a large domesticated seed and achene produced dates of 4130 +/- 40 y ears before the present (B.P.) and 4085 +/- 50 B.P., respectively. These di scoveries challenge the longstanding hypothesis that sunflower was domestic ated in eastern North America. Moreover, when considered with other recent discoveries on plant domestication, these data suggest a reconsideration of the idea that the eastern United States was an independent hearth for dome stication.