The Cambrian is a geologic period of the Paleozoic Era, spanning approximately 539–485 million years ago, characterized by a major diversification of multicellular life known as the Cambrian explosion. It follows the Ediacaran Period and precedes the Ordovician. Stratigraphically, its base is defined by the first appearance datum of complex trace fossils such as Treptichnus pedum, and it is subdivided into series and stages based on biostratigraphic markers, particularly trilobites and small shelly fossils. The Cambrian is critical for calibrating early Phanerozoic evolutionary, paleoenvironmental, and tectonic reconstructions.
The earliest evidence of spiders' fangs has been identified in a 518-million-year-old fossil by scientists at the University of Leicester and Yunnan University.
Evolution
Jul 1, 2026
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The way that Earth's first animals reproduced held back life's diversity for millions of years, until stress and competition led to the development of sexual reproduction, which in turn accelerated the pace of evolution.
Evolution
Jun 9, 2026
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Bryozoans are tiny, filter-feeding colonial invertebrates that thrive in the world's oceans today, yet for decades their origins presented a puzzling gap in the fossil record. While nearly every other major animal group made ...
Evolution
Jun 3, 2026
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Tracks left by some of the earliest complex animals are giving new insights into how they experienced the world. New research reveals how these creatures started to understand their surroundings, paving the way for animal ...
Evolution
Jun 2, 2026
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New research published in BMC Biology helps to fill in questions about the so-called "Furongian gap" from about 497 million to 485 million years ago, when paleontologists previously thought there were far fewer fossils than ...
Evolution
May 28, 2026
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From butterflies to blue whales, corals and worms, Earth is home to an incredible diversity of animals. How all of these animals evolved from earlier, simpler ancestors is one of the most exciting stories in the history book ...
Evolution
May 21, 2026
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More than 500 million years ago, during what is known as the Cambrian period, the seas and oceans on Earth were filled with a myriad of marine animals, many of which have now become extinct. This evolutionary burst in new ...
A reexamination of microfossils found in the Brazilian state of Mato Grosso do Sul shows that the marks previously interpreted as traces of worms or other small oceanic animals are actually communities of fossilized microscopic ...
Cell & Microbiology
May 11, 2026
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For decades, scientists have sought to explain the so-called "Cambrian Explosion," a pivotal period over 500 million years ago when a remarkable diversity of animal life appeared in the fossil record. But rather than a sudden ...
Evolution
May 5, 2026
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Scientists have uncovered the earliest fossil evidence of annelids (ringed worms) in Cambrian microfossils dating back approximately 535 million years ago. This discovery offers fresh insights into the origin and early evolution ...
Evolution
Apr 20, 2026
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