Schmidtiellus reetae (Image courtesy Brigitte Schoenemann et al.)

An article published in the journal “Proceedings of the National Academy of Sciences” describes the discovery of the oldest compound eye yet. It belongs to a trilobite of the species Schmidtiellus reetae that lived about 530 million years ago in today’s Estonia. The researchers were able to examine the structure of its eyes and also that of a specimen belonging to another species of trilobites called Holmia kjerulfi, about 2 million years younger. Both trilobites have an eye structure similar to that of many modern arthropods.

Reconstruction of Halszkaraptor escuilliei (Image courtesy Lukas Panzarin and Andrea Cau)

An article published in the journal “Nature” describes the discovery of a species of dinosaur related to Velociraptor but with semi-aquatic habits that lived about 75 million years ago in today’s Mongolia. Called Halszkaraptor escuilliei, it had physical characteristics and a life style closer to those of modern swans than to its cousins โ€‹โ€‹of the time. For this reason, a team of researchers led by Andrea Cau of the University of Bologna believes that it was part of a new group of dinosaurs.

Anchiornis huxleyi reconstruction (Image courtesy Rebecca Gelernter)

An article published in the journal “Palaeontology” describes a research on Anchiornis huxleyi, a small feathered dinosaur that lived about 160 million years ago in today’s China. Evan Saitta and Jakob Vinther of the British University of Bristol revealed new details on these animals’ plumage by examining a very well preserved specimen. Their conclusion is that this species had a fluffier look than the aerodynamic one of modern flying birds.

Oxygen increase measured in the Shingle Pass Limestone Formation (Image courtesy Cole Edwards)

An article published in the journal “Nature Geoscience” describes a research on the evolutionary radiation, in the sense of the quick diversification of new species, that happened in the Ordovician period, between 445-485 million years ago. Known as the Great Ordovician Biodiversification Event (GOBE), it led to a huge growth in the number of species and according to a team of researchers it was caused also by an 80% increase in oxygen levels in the air.

Jablonskipora kidwellae fossil (Photo courtesy Paul Taylor/London's Natural History Museum)

An article published in the journal “Papers in Palaeontology” describes the discovery of a species of bryozoan called Jablonskipora kidwellae which constitutes an evolutionary missing link. These are the first modern bryozoans that grew in a structure and their study could help shed light on the evolution of these small invertebrates that live in colonies and are part of a phylum that emerged in the Cambrian period, about 500 million years ago.