Scientists discovered a new microbe that could represent a missing link in the evolution of life as we know it at the bottom of the sea.
The study provides insight into how the complex cell types make up living beings evolved from simple microbes billions of years ago, Uppsala University reported.
The origin of these complex cell types has been a long-standing mystery, but the discovery of this new group of organisms could reveal the transition from simple to complex cells.
In the 1970s, the biologist Carl Woese identified a group of organisms called the Archaea, and demonstrated they represented a separate branch in the Tree of Life. The archaeal cells were small and simple, but were more closely related to organisms with complex cell types called eukaryotes. Scientists didn't understand how complex cell types from eukaryotes emerged from simple Archaea cells. This new microbe, dubbed Loki, may fill in the curious missing link. The organisms were discovered in sediment near super-hot deep sea vents.
"The puzzle of the origin of the eukaryotic cell is extremely complicated, as many pieces are still missing. We hoped that Loki would reveal a few more pieces of the puzzle, but when we obtained the first results, we couldn't believe our eyes. The data simply looked spectacular," said Thijs Ettema at the Department of Cell and Molecular Biology, Uppsala University, who lead the scientific team that carried out the study. "By studying its genome, we found that Loki represents an intermediate form in-between the simple cells of microbes, and the complex cell types of eukaryotes."
In the future the researchers hope to find more evidence of early cell evolution in future studies.
"In a way, we are just getting started. There is still a lot out there to discover, and I am convinced that we will be forced to revise our biology textbooks more often in the near future," Thijs Ettema concluded.
The findings were published in a recent edition of the journal Nature.
