Blogs about biology


An article published in the journal “Cell” describes a genetic research that focuses on the interbreeding between Homo Sapiens and Denisovans, a species of hominins known only thanks to a few bones that were preserved in conditions good enough to extract their DNA. A team of scientists at the University of Washington in Seattle compared the DNA of the Denisovans available with those of many modern humans from various different populations, concluding that there were at least two cases of interbreeding between the two species.

A female Eudorina colony with 32 large egg cells (Image courtesy Hiroko Kawai-Toyooka, University of Tokyo. All rights reserved)

An article published in the journal “Communications Biology” describes a research that offers new clues about the genetic origin of the two sexes. A team of researchers led by Dr. Hisayoshi Nozaki of the University of Tokyo studied the volvocine green algae, a group of algae that includes species that have been studied for years in the research on this topic. In this case the analyzes focused on species of the Yamagishiella and Eudorina genera, discovering a key gene in the differentiation between males and females.

Common raven (Corvus corax) (Photo National Park Service)

An article published in the journal “Nature Communications” brings evidence of an speciation reversal in two lineages of the species common raven (Corvus corax). A team of researchers examined genomic data from hundreds of ravens collected in North America in a study begun in 1999 concluding that this species diversified into three genetically distinct groups: the species Chihuahua raven (Corvus cryptoleucus) emerged from one of them but two of them are collapsing into one by a hybridization process.

Tupanvirus soda lake (Image Nature Communications)

An article published in the journal “Nature Communications” describes the discovery of two species of giant viruses that were called Tupanvirus, attributed to the Mimiviridae family, the same that includes other giant virus species discovered in recent years. A team of researchers from various international institutions discovered these two viruses that are larger than some bacteria and have some unusual characteristics for viruses, such as the genes for the synthesis of a lot of proteins.

Little skate - Leucoraja erinacea (Photo Andy Martinez/NOAA)

An article published in the journal “Cell” describes a research on the origin of the types of neurons needed to coordinate walking on the mainland. A team of researchers from the New York University School of Medicine focused in particular on the species little skate (Leucoraja erinacea), part of the most primitive vertebrate group, studying its neuromuscular and genetic development. The conclusion is that some fish started walking on the sea floor about 420 million years ago, about 20 million years before the early tetrapods started colonizing the mainland.