Spiders, crabs, and other arthropods evolved from a group of animals that underwent a burst of diversity around 500 million ...

part of the Paleozoic era, produced the most intense burst of evolution ever known. The Cambrian Explosion saw an incredible diversity of life emerge, including many major animal groups alive today.

Described in a study published in the journal Evolution & Development, this 555 million-year-old organism represents one of ...

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 ...

Until recently the fossils of organisms that lived earlier than the Cambrian period of 500 to 600 million years ago were rare. Now a wealth of such fossils has been found in South Australia ...

All animal evolution for the last half billion ... Recent research suggests that the period prior to the Cambrian explosion saw the gradual evolution of a "genetic tool kit" of genes that govern ...

Arthropods were the most diverse animal group in the Cambrian period and the Ordovician period that followed. The 452-million-year-old limestone slab shown here captures an Ordovician menagerie ...

During this period, simple trace fossils and tubular skeletons diversified. In the earliest Cambrian, organisms with hard ...

The history of life on Earth dates back more than 500 million years, when complex-structured organisms emerged during the Cambrian period. A recent discovery in the western Utah desert sheds light on ...

“Like many modern-day animal groups, ecdysozoans were prevalent in the Cambrian fossil record and we can see evidence of all three subgroups right at the beginning of this period, about 540 ...

data to show that continental clay export promoted organic carbon burial and thus atmospheric oxygenation during the Cambrian period.