A new study casts new light on evolution and produces the largest phylogenetic tree of life for seed plants to date.
Credit: Wikimedia
LONDON: The largest genome-based 'tree of life' ever constructed for seed plants has revealed the evolutionary relationships between 150 species.
Understanding the processes involved in the evolution of different plant species can help scientists to identify the importance of certain genes in plants, and could be used in agriculture to improve the quality of seeds.
"Ever since Darwin first described the 'abominable mystery' behind the rapid explosion of flowering plants in the fossil record, evolutionary biologists have been trying to understand the genetic and genomic basis of the astounding diversity of plant species," said Rob DeSalle, a corresponding author on the paper published in PLoS Genetics today, and researcher at the American Museum of Natural History in New York.
"Having the architecture of this plant tree of life allows us to start to decipher some of the interesting aspects of evolutionary innovations that have occurred in this group."
Understanding evolution through genes
Phylogenetics is the study of evolutionary relationships between different species and populations of organisms based on gene analysis. The results are presented in the form of a schematic 'tree' where divisions into branches indicate how different species diverged in the course of evolution.
Previous studies have examined a limited set of genes to create phylogenetic trees, whereas the new research uses nearly the entire genome - consisting of several thousand genes - of 150 different plant species.
Analysing via supercomputers
Performing genetic studies on such a vast number of genes in many species requires the power of supercomputers. These are able to analyse large sets of genetic data using algorithms that allow researchers to group the species according to their evolutionary relationships.
The new study results provide an unequivocal evolutionary tree of seed plants, supporting numerous hypotheses about their evolutionary relationships. And more importantly, by knowing all of the genes contained in all of the plants in the new phylogenetic tree, scientists are now able to highlight the specific genes that were crucially different at the point of evolutionary divergence.
"This makes it possible to generate radical new hypotheses on drivers of evolutionary innovation, as well as on the innovations themselves", commented Terry Hedderson, researcher at the University of Cape Town in South Africa, and an expert in the field of evolutionary plant biology.
Tree of life gone public
The acquired data and the software used in the study are now available to the public and can be used for further analyses. One such analysis could be a correlation of the groups of genes with certain functional processes and features, such as seed development or disease resistance, which may have agricultural benefits ranging from food to clothing.
According to Hedderson, the impact of this novel, functional phylogenetic approach on the field of evolutionary biology could be large. "Having the ability to link evolutionary divergences or points of diversification to specific genes or gene families will revolutionise evolutionary biology. This is thus a potential turning point in our understanding of how evolution has yielded what we see today," he said.
The benefit of the findings does not stop at seed plants, but may one day influence a large range of research areas. "In principle the methodology can be applied at any taxonomic level and to any group of organisms. I see the method as one that enables researchers to generate hypotheses about key genetic changes. These will feed into a large range of fields that can provide appropriate tests of these hypotheses," Hedderson added.
