An article published in the journal “Nature” reports a study that relaunches the idea that the Homo sapiens species emerged not from a single population that had e linear evolution but from different groups of genetically similar hominins that diversified and then interbred again. A team of researchers led by Brenna Henn of the University of California-Davis, USA, and Simon Gravel of McGill University in Montreal, Canada, conducted a genetic analysis and a comparison with early Homo sapiens fossils to try and locate the origin of modern humans. The researchers tested different evolutionary and migratory models and the one that best matches the data points to ramifications of African populations that subsequently interbred again until they merged.
An article published in the journal “Current Biology” reports a study on exceptionally preserved Rotadiscus grandis fossils. A team of researchers led by Dr Imran Rahman of the Natural History Museum in London offered many new insights into these animals dating back to the Lower Cambrian period, about 518 million years ago. Previous studies had left a number of questions about their classification and lifestyle. The new study assigns them to the large Ambulacraria group, which includes the Echinoderms and Hemicordata phyla and is part of the superphylum Deuterostomia together with the phylum of Chordates. If this classification is correct, it indicates that certain characteristics of later animal species emerged independently several times.
An article published in the journal “Nature” reports a study on archaea that belong to the proposed superphylum called Asgard and in particular on their characteristics that make them a possible evolutionary missing link with eukaryotes. A team of researchers formed by the collaboration of the working groups of Christa Schleper of the Austrian University of Vienna and Martin Pilhofer of ETH Zurich was successful in cultivating a species belonging to this group of microorganisms to study them in the laboratory. This allowed conducting thorough examinations of their cellular structures such as the extensive cytoskeleton.
An article published in the journal “Nature” reports the identification of a precursor of the tetrapods that lived on today’s Ellesmere Island, in Canada, in the Devonian period, about 375 million years ago. A team of researchers named it Qikiqtania wakei and illustrated similarities and differences with Tiktaalik roseae, the possible ancestor of today’s tetrapods. The anatomical characteristics of Qikiqtania wakei indicate that it descended from the precursors of the tetrapods that ventured to the mainland but unlike Tiktaalik roseae it went back to the water, where it developed fins suitable for aquatic life.
An article published in the journal “Nature” reports the results of a research on the correlation between climate changes that occurred over the last two million years and the evolution of human beings. A team of researchers led by Axel Timmermann, director of the IBS Center for Climate Physics (ICCP) at Pusan National University, South Korea, used ICCP’s Aleph supercomputer to simulate climate history. The results were compared with the largest database of human fossils and archaeological artifacts built under the direction of Pasquale Raia of the University of Naples Federico II, Italy. The result was that the best habitats for the human species that existed in these two million years match the climatic changes caused by the oscillation of the Earth’s axis and the periodic changes in the shape of the Earth’s orbit.