Evolution

Hydrothermal vents at Loki's Castle where Lokiarchaeota were found (Photo courtesy R.B. Pedersen, Centre for Geobiology (University of Bergen, Norway). All rights reserved)

In an article published in the journal “Nature”, an international team of researchers described the discovery of new microbes that constitute a missing link in the evolution of complex cells, those of eukaryotes. They were called Lokiarchaeota because they were found in a hydrothermal vent in the depths of the Atlantic Ocean between Greenland and Norway called Loki’s Castle.

An article published in the journal “Genome Biology” shows that many animals, including humans, acquired genes from microorganisms present in their environment in ancient times. This occurred through horizontal gene transfer (HGT), which transfers genetic material to cells that are not their descendants. The analysis of the genes of various species confirmed 17 genes previously identified as acquired in this way and identified another 128 in the DNA of humans.

Horizontal gene transfer has been known for a long time especially among microorganisms. It’s been identified in primitive multicellular creatures such as nematode worms and even in insects. Only in recent years studies started to assess it among complex plants and animals.

A rock containing 2.3 billion years old bacteria fossils, visible in dark areas (Image courtesy J. William Schopf/UCLA Center for the Study of Evolution and the Origin of Life. All rights reserved)

An international team of researchers discovered a type of deep-sea microorganism that appears to have remained unchanged for over 2 billion years. There are many species considered living fossils because they remained very similar in the course of many million of years but this is a really extreme case. Those are sulfu-cycling microorganisms that are now found in mud off the coast of Chile and are indistinguishable from fossils that date back to different past eras.

Fossil of Archaeopteryx lithographica at the Muséum national d'Histoire naturelle in Paris

The biggest project of genetic study of birds, called Avian Phylogenomics Consortium, has started giving results. 29 articles have been published of which 8 on a special issue of the journal “Science” and the other 21 in “Genome Biology”, “GigaScience” and other magazines. This project engaged for four years over two hundred scientists in many institutes of twenty nations that digged deep as never before with the study of the evolution of birds showing how there was a sort of Big Bang after the extinction of the dinosaurs.

A reconstruction of various species that belong to the phylum Vetucolia

A group of researchers at the University of Adelaide and the South Australian Museum in Australia published in the journal “BMC Evolutionary Biology” an article that explains why vetulicolians, which are those belonging to the phylum Vetulicolia, could be the strangest relatives of humans.

These creatures had lived in the Cambrian, 500 million years ago, and their fossils were discovered for the first time more than a century ago, in 1911, but their taxonomic status remained uncertain. After this new research, things could change.