If you have always wondered where we all come from, get ready to have your curiosity sated. According to a team of scientists, Luca is quite possibly the oldest ancestor of all living beings in the history of the planet. Referred to as the “last universal common ancestor“, it likely resided near a hydrothermal vent on the ocean floor some 4 billion years ago.
Recently published in the Nature journal, the research marks the first time that scientists have attempted to figure out the organism’s genetic structure. For the study, the team had to go through as many as 6 million genes, of which 355 seemed to belong to Luca. It is a well-known fact that genes undergo predictable changes over time.
Comparing the genome of living things, therefore, reveals information about organisms that have long ceased to exist. As part of the current project, scientist William Martin from Germany’s Heinrich Heine University and his team studied the genes of archaea and bacteria. These, according to the team, are two of the largest groups of single-celled beings.
If a particular gene is present in at least two bacterial groups as well as two groups of archaea, then it is highly likely that it belonged to our oldest common ancestor, Luca. Based on their research, the team concluded that Luca survived without oxygen, relying instead on hydrogen and carbon dioxide for energy. Furthermore, it was capable of withstanding very high temperatures, and also depended on metals for its survival.
Hydrothermal vents have long held the interest of scientists investigating the origin of life. This is because the seawater in such places is constantly heated by hot magma, thereby allowing a variety of unusual organisms to thrive. Despite its unique characteristics, Luca possesses only a handful of tools needed to build the essential nucleotides and amino acids.
According to the researchers, however, determining the exact period during which Luca existed has proved difficult. As pointed out by the team, further research is necessary to unravel the mysteries surrounding the earliest lifeforms.
Via: Tech Insider