 The name Pima was applied in honor of the Pima Indians, who helped raise the cotton on USDA experimental farms in Arizona in the early 1900s.The first clear sign of domestication of this cotton species comes from the Early Valdivia phase site of Real Alto on the coast of Ecuador (4400 BCE; calibrated radiocarbon dates) and from Ancon, on the Peruvian coast, where cotton bolls dating to 4200 BCE were found.According to other accounts, Real Alto cotton is dated to 3500–3000 BCE (uncalibrated radiocarbon years), and the oldest Cueva de Guitarrero in Anchash, Peru cotton is dated 8000 BCE.