But no such adaptive change is seen in collections of hoverflies made over the course of the past two centuries, suggesting that the imperfect mimics are stable in evolutionary terms.

ECONOMIST: Insects and mimicry

And yet the relation between economic data - which are often imperfect, and can only represent the state of an economy as it was some time in the past - and the future is tenuous at best.

BBC: A Point of View: And all shall worship money

"A few misguided appellate court decisions are threatening the imperfect but delicate balance of Hatch-Waxman, one that has yielded enormous benefits for consumers over the past 20-plus years, " Leibowitz said in prepared remarks.

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