Oral Paper

         Systematics

Cleaning the variable mess: a population genomics approach to understanding the evolutionary history of a complicated plant group

Presenting Author
Claire Marino
Description
The Solanum dioicum clade, which is a group of Australian bush tomatoes consisting primarily of species native to Western Australia and the Northern Territory, is a set of taxa whose species delimitations tend to be quite unclear. Since the publication of David Symon’s monograph A Revision of the Genus Solanum in Australia in 1981, little additional progress has been made in determining these relationships. In this project, a population genomics approach was used to analyze the relationships and delimitations between three species within the S. dioicum clade: Solanum dioicum, S. carduiforme, and S. ossicruentum. The use of population genomics methods is advantageous to understanding the fine-scale genetic diversity and population structures of species, especially given that phylogenetic approaches have not been successful in the past, and morphological approaches are not feasible. To complete this project, DNA extractions from different populations of the three aforementioned species were conducted prior to DNA sequencing, assembly, and data analyses that allowed the interpretation of these relationships. This project allows a continued and improved understanding of the relationships and delimitations between species within the S. dioicum clade. Our results indicate that there is a clear separation between the three studied species, and multiple genetic clusters within the S. dioicum populations, some of which may be their own independent taxa. In the context of global climate change, documenting species populations, particularly those which are rare or previously undocumented, helps regions that need extra protection get the resources they need, thereby protecting the biodiversity and stability of these habitats. It is extremely difficult to obtain the necessary resources to protect species if they have not been named or correctly described.