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Birds extend their ranges northwards.
Zaller, J.G. and Arnone III, J.A. 1997. Activity of surface-casting earthworms in a calcareous grassland under elevated atmospheric CO 2 . Zaller, J.G. and Arnone III, J.A. 1999. Interactions between plant species and earthworm casts in a calcareous grassland under elevated CO 2 .