Within every muscle of every living species with a backbone, a protein called myosin tugs on a partner protein to generate a ...

The sympathetic nervous system, which enables the fight-or-flight response, was thought to be present only in jawed vertebrates. Analysis of a jawless vertebrate suggests that this system might be a ...

Archaea are often mistaken as bacteria, given that both are small, single-cell organisms. However, archaea are as genetically different from bacteria as humans are from bacteria. While archaea are ...

Vertebrates have extremely different brain sizes: even with the same body size, brain size can vary a hundredfold. As a rule, mammals and birds have the largest brains in relation to their body size, ...

Researchers have long assumed that a tube in the famous Pikaia fossil ran along the animal’s back. But a new study turned the fossil upside down. By Carl Zimmer Over the past 500 million years, ...

A team of herpetologists at the Universidade Estadual de Santa Cruz just reported that a tiny frog found only in a hilltop forest in southern Bahia, Brazil, may be the smallest vertebrate in the world ...

The researchers from the HiLIFE Institute of Biotechnology, University of Helsinki compared two central bearded dragon lizards (Pogona vitticeps): a normal one and a mutant with no body scales. They ...

Walking is a complex mechanism involving both automatic processes and conscious control. Its dysfunction can have multiple, sometimes extremely subtle causes, within the motor cortex, brain stem, ...

Scientists reveal clues about the evolutionary origin of jaws by studying the embryonic development of zebrafish -- an approach known as 'evo-devo.' Using imaging and cell tracing techniques in ...

Researchers report February 15 in the journal Cell that ancient viruses may be to thank for myelin—and, by extension, our large, complex brains. The team found that a retrovirus-derived genetic ...

Scientists have long puzzled over the gap in the fossil record that would explain the evolution of invertebrates to vertebrates. Vertebrates, including fishes, amphibians, reptiles, birds, mammals, ...