Scientists redesign the tree of life to add a thousand species
Apparently, it's bacteria's world, and we're just living in it.
Scientists have been having a hard time figuring out where newly discovered organisms, such as giant viruses, fit in the tree of life. That's especially true for a particular group of researchers who unearthed 1,011 new species within the course of 15 years. In order to accommodate the new organisms they found -- and since life on Earth turned out to be more diverse than what previous generations of scientists thought -- they've decided that it's time to reinvent the evolutionary tree. Besides the 1,011 organisms they discovered, the team also studied the DNA of 2,072 known species to be able to get an accurate representation of nature's diversity.
The resulting diagram shows how the different types of Bacteria vastly outnumber those that fall under Archaea and Eukaryota, which includes humans. There's even a new and major branch under Bacteria called Canditate Phyla Radiation that's composed of microorganisms that lead symbiotic lifestyles, including parasites and those that benefit their hosts.
Jill Banfield, a UC Berkeley professor and the study's lead author, identified all these new bacteria with her colleagues by piecing together the genomes they gathered from the environment. They got their samples from meadow soils, water geysers, deserts and even from the mouth of a dolphin. They might not have seen these organisms yet, much less grown them in a lab, but they already know their DNA makeup.
The team believes their work could benefit not just microbiologists, but also biochemists looking for novel genes, as well as researchers studying evolution. Co-author Brett Baker said "[t]his incredible diversity means that there are a mind-boggling number of organisms that we are just beginning to explore the inner workings of that could change our understanding of biology."
