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Evidence of possibly the oldest forms of life on Earth has been found in hydrothermal vent precipitates. [1]The earliest known life forms on Earth may be as old as 4.1 billion years (or Ga) according to biologically fractionated graphite inside a single zircon grain in the Jack Hills range of Australia. [2]
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.
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
A team of international researchers has challenged the long-held belief that complex life forms first emerged on Earth 635 million years ago, presenting findings that show life may have existed ...
Stromatolites are a major constituent of the fossil record of the first forms of life on Earth. [24] They peaked about 1.25 billion years ago (Ga) [22] and subsequently declined in abundance and diversity, [25] so that by the start of the Cambrian they had fallen to 20% of their peak.
Artist's conception of Hadean Eon Earth, when it was much hotter and inhospitable to all forms of life. The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to ...
The Burgess Shale was first discovered in 1909 by Charles D. Walcott, secretary of the Smithsonian Institution in Washington, DC. The 508 million-year-old site is a gold mine of well-preserved ...
The Ediacaran (/ ˌ iː d i ˈ æ k ər ə n /; formerly Vendian) biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (c. 635–538.8 Mya). These were enigmatic tubular and frond-shaped, mostly sessile, organisms.