The Forum for History of Human Science is pleased to award its essay prize for 2001 to Jorge Canizares Esguerra for his essay "New World, New Stars: Patriotic Astrology and the Invention of Spanish and Creole Bodies in Colonial Spanish America, 1600-1650," published in the American Historical Review in 1999. The essay, distinguished by its breadth of learning and originality of interpretation, shows how the settlers of Spanish America drew upon European traditions of theology, astrology, and astronomy to create novel explanations for racial differences, which justified the hierarchical order of their settlements. These schemes of racialized physiology developed by Spanish colonial intellectuals have not received scholarly attention because they had virtually no impact on later European models of scientific racism, but they provide significant insights into the mindset of the ruling class during the early modern period. In his essay, Canizares makes a distinctive contribution to the history of ideas about human differences--an exposition of the exploited possibilities of elaboration of seventeenth-century scientific notions--and also enriches the history of colonialism, showing the relationship between colonies and metropoles to have been far more complex than we have been accustomed to believe.