For over half a billion years, evolution has sculpted the nervous systems of bilaterian animals, equipping them with ...

The Cambrian Explosion saw an incredible diversity of life emerge, including many major animal groups alive today. Among them were the chordates, to which vertebrates (animals with backbones ...

This animation created for Evolution: "Great Transformations" depicts creatures whose fossils were found at the Burgess Shale. As alien as these creatures seem, they are also surprisingly familiar.

dramatically. It was the time of the Cambrian Explosion, an eruption of life when Earth’s very first animals began appearing in the fossil record — the ancestors of all major animal groups ...

Worminess wasn’t the only factor that brought oblivion to the Ediacarans and triggered the Cambrian explosion—there also were changes in ocean chemistry that allowed animals to acquire hard ...

Dr María Herranz noted, "The emergence of paired nerve cords likely facilitated greater coordination of movement, particularly in segmented animals. During the Precambrian-Cambrian transition ...

Patches of photosensitive cells were probably common long before the Cambrian, allowing early animals to detect light and sense what direction it was coming from. Such rudimentary visual organs ...

Dr. María Herranz noted, "The emergence of paired nerve cords likely facilitated greater coordination of movement, particularly in segmented animals. During the Precambrian-Cambrian transition ...

“The emergence of paired nerve cords likely facilitated greater movement coordination, particularly in segmented animals. During the Precambrian-Cambrian transition, changes in the nervous and ...

Dr María Herranz noted, “The emergence of paired nerve cords likely facilitated greater coordination of movement, particularly in segmented animals. During the Precambrian-Cambrian transition, changes ...