This daily feast-and-famine cycle in oxygen availability created an intense physiological challenge for early animals, ...

3 min read The Cambrian period, part of the Paleozoic era ... including many major animal groups alive today. Among them were the chordates, to which vertebrates (animals with backbones) such ...

Animals living about 500 million years ago spent time on mudflats that were periodically exposed to the air. The finding suggests that some of the earliest animals were able to survive outside of ...

Some of the best information about early animals comes from fossils dating back to the Cambrian period, which started around 541 million years ago. During this time, Earth experienced a burst of ...

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 ...

This discovery provides more insight into how animals evolved from single ... of that latter phenomenon is the Cambrian Explosion—the geologic period some 530 million years ago when Earth ...

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 ...

Some animals could likely tell the difference between light and dark, but they never knew whether that looming shadow was a friend or foe. Then, at the beginning of the Cambrian Period, life opened ...

visitors can follow fossil evidence tracing the evolution of life during the Cambrian period — the first geological period of the Paleozoic era — which lasted from 541 million to 485 million ...

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 ...