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- Cambrian - Wikipedia
Currently the boundaries of the Cambrian System, three series and six stages are defined by global stratotype sections and points [1] The lower boundary of the Cambrian was originally held to represent the first appearance of complex life, represented by trilobites
- Cambrian Period | Definition, Plants, Animals | Britannica
Cambrian Period, earliest time division of the Paleozoic Era, extending from 538 8 million to 485 4 million years ago
- Cambrian Period—541 to 485. 4 MYA - U. S. National Park Service
The Cambrian Period marks an important point in the history of life on Earth; it is the time when many kinds of invertebrates and the first vertebrates—fishes—appeared in the fossil record
- The Cambrian Period
The Cambrian world was bracketed between two ice ages, one during the late Proterozoic and the other during the Ordovician During these ice ages, the decrease in global temperature led to mass extinctions
- Cambrian Period: When Life Learned to Experiment - FossilEra
From insects and mollusks to fish, reptiles, and mammals, the roots of modern life trace back to those shallow Cambrian seas Preserved in layers of shale and limestone, the Cambrian fossil record captures the moment when life stopped merely surviving and began truly evolving
- Cambrian Period | Natural History Museum
The Cambrian* Period begins the Phanerozoic Eon, the last 542 million years during which fossils with hard parts have existed It is the first division of the Paleozoic Era (542Ma -251Ma)
- Cambrian explosion - Wikipedia
Opabinia made the largest single contribution to modern interest in the Cambrian explosion
- Cambrian Period - Fossils, Rocks, Animals | Britannica
Cambrian rocks have a special biological significance, because they are the earliest to contain diverse fossils of animals These rocks also include the first appearances of most animal phyla that have fossil records
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