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The Cambrian explosion (also known as Cambrian radiation [1] or Cambrian diversification) is an interval of time beginning approximately in the Cambrian period of the early Paleozoic, when a sudden radiation of complex life occurred and practically all major animal phyla started appearing in the fossil record.
By the middle of the following Cambrian Period, a very diverse fauna is recorded in the Burgess Shale, including some which may represent stem groups of modern taxa. The increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life. [30] [31]
Awramik (1973) suggested that the appearance about 700 million years ago of protists (single-celled eukaryotes) that "cropped" microbial mats greatly expanded food chains, and thus allowed rapid diversification, which led to the Cambrian explosion, [7] but "cropping" is now thought to have arisen before 1 billion years ago, as stromatolites ...
The earliest evidence for life on Earth includes: 3.8 billion-year-old biogenic hematite in a banded iron formation of the Nuvvuagittuq Greenstone Belt in Canada; [30] graphite in 3.7 billion-year-old metasedimentary rocks in western Greenland; [31] and microbial mat fossils in 3.48 billion-year-old sandstone in Western Australia.
A new study says complex life began 1.5 billion years ... complex life likely formed during the Ediacaran Period some 600 million years ago—right on the cusp of the well-known Cambrian Explosion.
The Precambrian dates from around 3850 to 542 million years ago. The Neoproterozoic is characterized by a large glaciation event, followed by the appearance of the first multicellular body plans before the Cambrian Explosion. Until the late 1950s, the Precambrian was not believed to have hosted multicellular organisms.
Exceptionally well preserved 500m year old fossils show Cambrian seas were more diverse than scientists had thought. Exquisite fossil finds shed new light on the 'Cambrian explosion', when oceans ...
The Cambrian is the first period of the Paleozoic Era and ran from 539 million to 485 million years ago. The Cambrian sparked a rapid expansion in the diversity of animals, in an event known as the Cambrian explosion , during which the greatest number of animal body plans evolved in a single period in the history of Earth.