Diversity through multiculturality: Assessing migrant choice policies in an island model.
Lourdes Araujo, Juan J. Merelo.
IEEE Transactions on Evolutionary Computation, 15(4), pp. 456-469 (2011).

The natural mate-selection behavior of preferring
individuals which are somewhat (but not too much) different
has been proved to increase the resistance to infection of the
resulting offspring, and thus fitness. Inspired by these results
we have investigated the improvement obtained from diversity
induced by differences between individuals sent and received
and the resident population in an island model, by comparing
different migration policies, including our proposed multikulti
methods, which choose the individuals that are going to be
sent to other nodes based on the principle of multiculturality;
the individual sent should be different enough to the target
population, which will be represented through a proxy string
(computed in several possible ways) in the emitting population.
We have checked a set of policies following these principles
on two discrete optimization problems of diverse difficulty for
different sizes and number of nodes, and found that, in average
or in median, multikulti policies outperform the usual policy of
sending the best or a random individual; however, the size of this
advantage changes with the number of nodes involved and the
difficulty of the problem, tending to be greater as the number
of nodes increases. The success of this kind of policies will be
explained via the measurement of entropy as a representation of
population diversity for the policies tested.