User:Mblick2/sandbox

In cladistics, a homoplasy or a homoplastic character state is a trait (genetic, morphological etc.) that is shared by two or more taxa because of convergence, parallelism or reversal.[2] In other terms, homoplasy is the evolution of similar traits in unrelated organisms. These traits can be both physical and behavioral (Rendall et al. 2007, Sanerson et al. 1989). Physically, homoplasy can be seen both at the macro and micro levels. Molecular homoplasy can be seen in the similarity among the proteins in plant chloroplasts (Kallersjo et al. 1999) while physical homoplasy can be seen when comparing the wings of birds and bats. Homoplastic characters typically arise from the processes or convergence, parallelism, and reversal. Convergence is when the same trait arises independently in two organisms (Hall 2003). The traits may arise from the same gene or genetic pathway or be completely unrelated, but have developed separately in each organism’s lineage. Parallelism is similar, but is the development of traits in related organisms. These traits generally follow similar developmental pathways in each organism (Hall 2003). The third category, reversals, are when a feature is similar to an ancestral feature. Such features may have been lost and regain in the organisms’ lineage, and does not necessarily come from the same genetic pathway each time (Hall 2003)