TY - JOUR A2 - Wang, Wen AU - Swithers, Kristen S. AU - Soucy, Shannon M. AU - Gogarten, J. Peter PY - 2012 DA - 2012/07/12 TI - The Role of Reticulate Evolution in Creating Innovation and Complexity SP - 418964 VL - 2012 AB - Reticulate evolution encompasses processes that conflict with traditional Tree of Life efforts. These processes, horizontal gene transfer (HGT), gene and whole-genome duplications through allopolyploidization, are some of the main driving forces for generating innovation and complexity. HGT has a profound impact on prokaryotic and eukaryotic evolution. HGTs can lead to the invention of new metabolic pathways and the expansion and enhancement of previously existing pathways. It allows for organismal adaptation into new ecological niches and new host ranges. Although many HGTs appear to be selected for because they provide some benefit to their recipient lineage, other HGTs may be maintained by chance through random genetic drift. Moreover, some HGTs that may initially seem parasitic in nature can cause complexity to arise through pathways of neutral evolution. Another mechanism for generating innovation and complexity, occurring more frequently in eukaryotes than in prokaryotes, is gene and genome duplications, which often occur through allopolyploidizations. We discuss how these different evolutionary processes contribute to generating innovation and complexity. SN - 2090-8032 UR - https://doi.org/10.1155/2012/418964 DO - 10.1155/2012/418964 JF - International Journal of Evolutionary Biology PB - Hindawi Publishing Corporation KW - ER -