Scientists from different institutions worked altogether in creating a first draft of the "tree of life" showing nearly 2.3 million identified species in Earth.

The newly released tree of life shows different species of animals, plants, fungi and microbes, and their relationships that developed for the past 3.5 billion years ago.

Stephen Smith, study leader and an evolutionary biologist from the University of Michigan, worked with his colleagues in piecing together 484 published trees of life to make a single tree.

"This is the first real attempt to connect the dots and put it all together," Karen Cranston, principal investigator from Duke University, said in a university news release. "Think of it as Version 1.0."

It took the scientists 3 years to complete the new tree using software tools and algorithms to ensure balance and efficiency when merging hundreds of trees.

"Our software, which is called 'treemachine,' took a few days to generate the current draft tree of life on a moderately outfitted desktop workstation in Stephen's office. For comparison, other state-of-the-art methods we tried would have taken hundreds of years to finish on that kind of hardware," Cody Hinchliff, formerly a postdoctoral researcher in Smith's lab who is now at the University of Idaho, said.

The tree of life will be useful to scientists because it will help them better understand how different species are related to each other. Such knowledge will allow scientists to develop new drugs, new methods to increase the production of food, and stop the spread of infectious diseases such as HIV, Ebola, and influenza.

Smith is hoping that other researchers would contribute more information and share their studies to make the tree more complete. They developed a software that will allow researchers to update the tree with new data, especially that there are more species that are yet to be discovered.

"This is just the beginning," Smith said. "While the tree of life is interesting in its own right, our database of thousands of curated trees is an even more useful resource. We hope that this publication will encourage other researchers to contribute their own studies or to enter information from previously published sources."

The paper was published in the Sept. 19 issue of the Proceedings of the National Academy of Sciences.