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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 Plesiadapiformes very likely contain the ancestor species of all primates. [24] They first appeared in the fossil record around 66 million years ago, soon after the Cretaceous–Paleogene extinction event that eliminated about three-quarters of plant and animal species on Earth, including most dinosaurs. [25] [26]
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 ...
All life on Earth can be traced back to a Last Universal Common Ancestor, or LUCA. A new study suggests that this organism likely lived on Earth only 400 million years after its formation.
While the Cambrian Explosion kickstarted complex life in a major way some 530 million years, the true timeline of life on Earth is much longer. For years, scientists have estimated that LUCA ...
List of timelines; Chronology; See calendar and list of calendars for other groupings of years. See history, history by period, and periodization for different organizations of historical events. For earlier time periods, see Timeline of the Big Bang, Geologic time scale, Timeline of evolution, and Logarithmic timeline
For decades, scientists have theorized that volcanic lightning on an early Earth played a crucial role in kickstarting life on the planet by breaking molecules into useful, biological components.
A variation of this analogy instead compresses Earth's 4.6 billion year-old history into a single day: While the Earth still forms at midnight, and the present day is also represented by midnight, the first life on Earth would appear at 4:00 am, dinosaurs would appear at 10:00 pm, the first flowers 10:30 pm, the first primates 11:30 pm, and ...