Artistic representation of a Pentecopterus decorahensis (Image courtesy Patrick Lynch / Yale University. All rights reserved)

An article in the journal “BMC Evolutionary Biology” describes the discovery of fossils of Pentecopterus decorahensis, a sea scorpion that lived in the Ordovician period, about 467 million years ago, in Iowa. It was huge by arthropods standards because it’s estimated that its length could reach 180 cm (almost 6 feet). It’s in fact one of the largest arthropods ever lived and according to James Lamsdell, the lead author of this study, was part of a group of important predators in the Paleozoic era.

Catopsbaatar catopsaloides, an ancient mammal that belonged to the multituberculates order

An article published in the journal “Current Biology” describes a research showing that there was a rapid evolution of mammals during the Jurassic period, between 200 and 145 million years ago. That period and in general the Mesozoic era, between 252 and 66 million years ago, were the dinosaurs era so we tended to think that mammals lived in their shadow, in ecological niches, such as nocturnal insectivores. Instead, the discovery of new fossils in recent years showed a series of adaptations with a previously unknown diversification.

Aegirocassis benmoulai fossil and scheme

An article recently published in the “Journal of the Geological Society” describes a research on the fossils of the Lower Fezouata formation in the south-east of Morocco, a deposit discovered only five years ago. These fossils shed light on the evolution of many families of animals in the Ordovician period, between 485 and 444 million years ago. In particular, it shows that some of the oldest animals survived millions of years longer than it was inferred from previously found fossils.

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.