So the distribution of mimetic species should be one of local clusters of good mimics, against a wider background of poor ones which may mean that a poorly mimetic species outnumbers a good one.

ECONOMIST: Insects and mimicry

Under a new local policing model, safer neighbourhood teams will focus on clusters of wards, Local Police Areas.

BBC: Met Police plan outlines targets and confirms closures

Such investments have stimulated clusters of high-tech local firms.

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