Character displacement in some Cnemidophorus lizards revisited: A phylogenetic analysis

摘要

Ecological studies have demonstrated the role of competition in structuring communities; however, the impor- tance of competition as a vehicle for evolution by natural selection and speciation remains unresolved. Study systems of insular faunas have provided several well known cases where ecological character displacement, coevolution of competitors leading to increased morphological separation, is thought to have occurred (e.g., anoline lizards and geospizine finches). Whiptail lizards (genus Cnemidophorus) from the islands of the Sea of Cortez and the surrounding mainland demonstrate a biogeo- graphic pattern of morphological variation suggestive of char- acter displacement.