Rapid evolution of a native species following invasion by a congener

In recent years, biologists have increasingly recognized that evolutionary change can occur rapidly when natural selection is strong; thus, real-time studies of evolution can be used to test classic evolutionary hypotheses directly. One such hypothesis is that negative interactions between closely related species can drive phenotypic divergence. Such divergence is thought to be ubiquitous, though well-documented cases are surprisingly rare. On small islands in Florida, we found that the lizard Anolis carolinensis moved to higher perches following invasion by Anolis sagrei and, in response, adaptively evolved larger toepads after only 20 generations. These results illustrate that interspecific interactions between closely related species can drive evolutionary change on observable time scales.,
Exp.PerchHeight_19951998_Data.Acarolinensis
This .Rdata file contains an object (Exp.PerchHeight19951998_Data_Acarolinensis) that contains perch height (cm), island (small, medium, or large), sex, and treatment (0=control, 1=treatment) information for Anolis carolinensis. These data were used to create Figure 1. Mixed models R-code for two-way interaction (package nlme) which includes the pre introduction data mixed.phl.2way.b <- lme(sqrt(PH)~ as.factor(Treat)*as.factor(Event) + Sex, random =~Sex | as.factor(Island), na.action=na.omit) Mixed models R-code for two-way interaction (package nlme) which does not include the pre introduction data mixed.phl.2way.no.pre <- lme(sqrt(PH)~ as.factor(Treat)*as.factor(Event) + Sex, random =~Sex | as.factor(Island), na.action=na.omit)
 

Exp.PerchHeight_19951998_Data_Asagrei
This .Rdata file contains an object (“x”) that contains perch height (cm), island/treatment (small treatment, medium treatment, or large treatment), and sex (0=f, 1=m) i...,