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Charmantier A, Sheldon BC.Charmantier A, et al. Among authors: sheldon bc.Trends Ecol Evol. 2006 Aug;21(8):417-9. doi: 10.1016/j.tree.2006.06.001. Epub 2006 Jun 16.Trends Ecol Evol. 2006.PMID: 16782227