For evolutionary biologists, introductions can also be important to understand processes of evolution.
As stated in the "Introduction," evolutionary medicine is not a field, and I would not want the existence of these courses with that phrase in their titles to suggest as much.
For instance, the placement of Urochordate sequences offered little or no support for the proposed evolutionary scenario (see Introduction).
Invasive species with global distributions are interesting for studying evolution because the different introduced populations of global invaders can serve as natural replicates for studying the evolutionary responses to introduction.
Studies examining the plasticity of phenology in non-native species may also want to consider how much evolutionary change following introduction has contributed to this plasticity (e.g. Sultan et al. 2013), and how quickly species can genotypically adjust to more static phenological cues post-invasion.
Thus, a more gradual and explicit instructional focus on the development of foundational aspects of evolutionary reasoning before introduction of the use of complex graphical representations, such as phylogenetic trees in systematics problem-solving, might be required to help students effectively meet the "tree thinking challenge" (Baum et al., 2005).
Although R. ponticum is very long-lived, it was introduced 200 250 years ago, and there has been time for post-introduction evolutionary change.
As individuals from some of those field surveys were included in this common garden, it seems likely that these patterns are driven by environmental field conditions rather than post-introduction evolutionary change.
This may be a result of the phenotypic plasticity of the species (Chun 2011; Godoy et al. 2011), propagule pressure (the number of individuals released and the number of release events; Lockwood et al. 2005, but see Nuñez et al. 2011) and post-introduction evolutionary processes like inbreeding, drift, hybridization and response to novel selection pressures (Lee 2002; Prentis et al. 2008).
Evidence on the evolution of invasiveness in plants is still limited (Barrett et al. 2008; Prentis et al. 2008), but the consensus is that invasiveness in exotic species introduced outside their range can sometimes result from post-introduction evolutionary change (Schierenbeck and Ellstrand 2009).
