A genetic history of the pre-contact Caribbean.

Humans settled the Caribbean about 6,000 years ago, and ceramic use and intensified agriculture mark a shift from the Archaic to the Ceramic Age at around 2,500 years ago. Here we report genome-wide data from 174 ancient individuals from The Bahamas, Haiti and the Dominican Republic (collectively, Hispaniola), Puerto Rico, Curaçao and Venezuela, which we co-analysed with 89 previously published ancient individuals. Stone-tool-using Caribbean people, who first entered the Caribbean during the Archaic Age, derive from a deeply divergent population that is closest to Central and northern South American individuals; contrary to previous work, we find no support for ancestry contributed by a population related to North American individuals.

Association between Characteristics of Impostor Phenomenon in Medical Students and Step 1 Performance.

Impostor phenomenon (IP) is a widely recognized experience in which highly performing individuals do not internalize success. Self-doubt toward one's ability or intelligence is unexpectedly common. Prior research has associated IP with medical student perceptions, burnout, and demographic characteristics.