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.

Speciman of gray bichir, also known as the Senegal bichir or Cuvier's bichir, formally Polypterus senegalus senegalus

The research on the evolution of the fish that gave rise to the tetrapods gradually adapting to life on land are generally carried out by examining fossils such as the Tiktaalik roseae, a species dating back to the Devonian period, about 375 million years ago. Instead, a study published in the journal “Nature” was conducted by three scientists from McGill University in Montreal, Canada, studying modern fishhes, the gray bichir, also known as the Senegal bichir or Cuvier’s bichir (scientific name Polypterus senegalus), studying their behavior on land.

Reconstruction of Hallucigenia sparsa

Hallucigenia, an animal lived in the Cambrian period, between 520 and 505 million years ago, has been considered for decades a really weird animal, hence the name. It looked like it could be part of a family that got extinct but the discovery of new fossils allowed to study it better since the ’90s. Now according to a new research carried out at the University of Cambridge hallucigenia, or rather the hallucigenia genus, is a lobopode, related to modern velvet worms, part of the Onychophora phylum.