Competition, predation and natural selection in island lizards

Arising from R. Calsbeek & R. M. Cox 465, 613-616 (2010); Calsbeek and Cox replyDiscerning the relative influence of competition and predation as selective forces is an important goal of evolutionary ecology. Calsbeek and Cox argue that intraspecific competition outweighs predation as an agent of natural selection on island populations of the lizard Anolis sagrei. However, we identify several problems with the design and analysis of the Calsbeek and Cox study that we believe render its results uninterpretable. © 2011 Macmillan Publishers Limited. All rights reserved.