WASHINGTON, (Reuters) – Deep beneath the Atlantic Ocean between Greenland and Norway, scientists have found microorganisms they call a missing link connecting the simple cells that first populated Earth to the complex cellular life that emerged roughly 2 billion years ago.
The researchers said on Wednesday a group of microorganisms called Lokiarchaeota, or Loki for short, were retrieved from the inhospitable, frigid seabed about 1.5 miles (2.35 km) under the ocean surface not too far from a hydrothermal vent system called Loki’s Castle, named after a Norse mythological figure.
The discovery provides insight into how the larger, complex cell types that are the building blocks for fungi, plants and animals including people, a group called eukaryotes, evolved from small, simple microbes, they said.
The Lokiarchaeota are part of a group called Archaea that have relatively simple cells lacking internal structures such as a nucleus. But the researchers found the Lokiarchaeota share with eukaryotes a significant number of genes, many with functions related to the cell membrane.
These genes would have provided Lokiarchaeota “with a ‘starter-kit’ to support the development of cellular complexity,” said evolutionary microbiologist Lionel Guy of Sweden’s Uppsala Univer-sity. Archaea and bacteria, another microbial form, are together known as prokaryotes.
“Humans have always been interested in trying to find an answer to the question, ‘Where do we come from?’ Well, now we know from what type of microbial ancestor we descend,” said Uppsala University evolutionary microbiologist Thijs Ettema, who coordinated the study.
