In a groundbreaking study, scientists have discovered that eukaryotic cells, including those of humans, plants, and animals, evolved from a group of ancient microbes called Asgard archaea. Researchers found that Asgard archaea are closely related to eukaryotes and share many genes, suggesting a common ancestor that gave rise to both groups. The study suggests that complex life forms like ours originated from a simple microbe in hot environments.
The team analyzed DNA samples from various sediments and hydrothermal vents, recovering 63 new Asgard genomes. By comparing these genomes with those of eukaryotes, the researchers built evolutionary trees that show eukaryotes as a “well-nested clade” within Asgard archaea. This finding supports the idea that complex cells arose from within the archaeal domain rather than from a separate branch.
The study also reveals that the common ancestor of Asgard archaea and eukaryotes likely had a chemolithotrophic lifestyle, using inorganic carbon compounds to build organic molecules. Over time, this lineage shifted to heterotrophy, gaining energy from organic compounds. The predicted central carbon metabolism at different stages included pathways similar to those in modern eukaryotic cells.
The team’s findings provide new insights into the origins of complex life and suggest that studying simpler forms of life can reveal valuable information about themselves. With this discovery, scientists have shed light on the evolutionary history of eukaryotes and provided a fascinating glimpse into their ancient past.
Source: https://www.earth.com/news/humans-and-all-life-on-earth-may-have-spawned-from-asgard-archaea-eukaryotes