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The theory of panspermia speculates that life on Earth may have come from biological matter carried by space dust [93] or meteorites. [94] While current geochemical evidence dates the origin of life to possibly as early as 4.1 Ga, and fossil evidence shows life at 3.5 Ga, some researchers speculate that life may have started nearly 4.5 billion ...
The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites
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 ...
From its earliest appearance at about 1.9 Ma, H. erectus is distributed in East Africa and Southwest Asia (Homo georgicus). H. erectus is the first known species to develop control of fire, by about 1.5 Ma. H. erectus later migrates throughout Eurasia, reaching Southeast Asia by 0.7 Ma. It is described in a number of subspecies. [38]
The Precambrian (/ p r i ˈ k æ m b r i. ə n,-ˈ k eɪ m-/ pree-KAM-bree-ən, -KAYM-; [2] or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon.
A new study suggests that cloud-to-ground lightning likely provided the necessary material for the first organisms on Earth to form. ... early Earth life forms, and provide a template for how life ...
The earliest widely agreed upon evidence of life — and fresh water — comes from stromatolites, fossilized microbes that formed mounds in hot springs 3.5 billion years ago, Gamaleldien said.
c. 4,300 Ma – Nectarian Era begins on Earth. c. 4,250 Ma – Earliest evidence for life, based on unusually high amounts of light isotopes of carbon, a common sign of life, found in Earth's oldest mineral deposits located in the Jack Hills of Western Australia. [4] c. 4,100 Ma – Early Imbrian Era begins on Earth.