Charting the Evolutionary History of Life

The synthesis of all known species into one tree of life has been avoided by the scientific community—until now. In an effort spanning three years, researchers from thirteen institutions collaborated to complete the first draft of a comprehensive new tree of life that depicts the evolutionary sequence of 2.3 million species as they emerged from one another over time.

“Despite decades of effort and thousands of phylogenetic studies on diverse clades, we lack a comprehensive tree of life, or even a summary of our current knowledge,” the researchers note. With an estimated 15,000 new species identified each year, they speculate the lack of a universal tree has been due to the daunting nature of the task and the lack of appropriate data collection. Researchers found that only one in six studies publish data in a downloadable format appropriate for their diagram. As a result, some aspects of the tree remain a mystery. On the bright side, this comprehensive tree of life uses an automated digital format which allows the researchers to bring already published trees together in order to describe the interconnected evolutionary history of animals, plants, and microbes. In a Reddit AMA (“Ask Me Anything”), researcher Karen Cranston writes, “One of the things that we hope this research will do is highlight how much of our phylogenetic knowledge is not digitally available and motivate people to publish their data.” To promote this, researchers created the Open Tree of Life, a community-driven project that allows users to continuously update the tree of life database as new sub-trees become available through data sharing and comment forms. Researchers hope that this effort will reveal significant gaps in sampling, demonstrate the importance of electronic data, and provide a valuable resource. Researcher Cody Hinchliff explains:

Understanding these relationships allows us to think about how the evolutionary process may have occurred, and we can combine this understanding with other information (such as the environmental conditions we think were happening at the time) to start making educated guesses about why evolution may have worked in certain ways. This in turn allows us to start making predictions about how evolution may work in general. In specific cases such as viral evolution, we may even be able to think about how to take advantage of our knowledge in order to design more effective treatments. In the case of higher taxa, understanding the evolutionary process helps us think more clearly about the way Earth’s biodiversity has accumulated, which is important for conservation.

The rate at which species go extinct has increased 1,000 times since humans came into the picture, with future extinction rates projected to reach 10,000 times greater. With this in mind, it is important to be reminded of our shared evolutionary history and our not-so-distant relationship with other forms of life. The Open Tree of Life provides a stunning resource that allows us to communicate with the history of biodiversity and serves as a reminder that we are not the center (in fact, there is no circle) of life.Tags: evolution