One of the most profound ideas to emerge in modern science is Charles Darwin's concept that all of life, from the smallest microorganism to the largest vertebrate, is connected through genetic relatedness in a vast genealogy. This "Tree of Life" summarizes all we know about biological diversity and underpins much of modern biology, yet many of its branches remain poorly known and unresolved.
To help scientists discover what Darwin described as the tree's "everbranching and beautiful ramifications," the National Science Foundation (NSF) has awarded $17 million in "Assembling the Tree of Life" grants to researchers at more than 25 institutions. Their studies range from investigations of entire pieces of DNA to assemble the bacterial branches; to the study of the origins of land plants from algae; to understanding the most diverse group of terrestrial predators, the spiders; to the diversity of fungi and parasitic roundworms; to the relationships of birds and dinosaurs.
"Despite the enormity of the task," said Quentin Wheeler, director of NSF's division of environmental biology, which funded the awards, "now is the time to reconstruct the tree of life. The conceptual, computational and technological tools are available to rapidly resolve most, if not all, major branches of the tree of life. At the same time, progress in many research areas from genomics to evolution and development is currently encumbered by the lack of a rigorous historical framework to guide research." Scientists estimate that the 1.75 million known species are only 10 percent of the total species on earth, and that many of those species will disappear in the decades ahead. Learning about these species and their evolutionary history is epic in its scope, spanning all the life forms of an entire planet over its several billion year history, said Wheeler.
Why is assembling the tree of life so important? The tree is a picture of historical relationships that explains all similarities and differences among plants, animals and microorganisms. Because it explains biological diversity, the Tree of Life has proven useful in many fields, such as choosing experimental systems for biological research, determining which genes are common to many kinds of organisms and which are unique, tracking the origin and spread of emerging diseases and their vectors, bio-prospecting for pharmaceutical and agrochemical products, developing data bases for genetic information, and evaluating risk factors for species conservation and ecosystem restoration.
The Assembling the Tree of Life grants provide support for large multi-investigator, multi-institutional, international teams of scientists who can combine expertise and data sources, from paleontology to morphology, developmental biology, and molecular biology, says Wheeler. The awards will also involve developing software for improved visualization and analysis of extremely large data sets, and outreach and education programs in comparative phylogenetic biology and paleontology, emphasizing new training activities, informal science education, and Internet resources and dissemination.