 Moreover, McKenzie and Rapoport also observe that the presence of migrant networks drives self-selection, with Mexican communities with strong migrant networks "sending" typically less educated members to the US compared with communities with weaker networks, in line with Borjas (1987) and Chiquiar and Hanson (2005).Another nexus of McKenzie's research on migration has been migration in the Pacific.In work with John Gibson, McKenzie notably found that the desire to maximize income cannot explain migration patterns among the very highly skilled, with many potential emigrants - especially those more risk averse, impatient or inept at foreign languages - deciding not to emigrate despite very high returns to migration, whereas many emigrants - especially those with strong ties to homebound family or who didn't emigrate for reasons of lifestyle - choose to return even though doing so implies forgoing large sums of income.