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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 ...
[10] [11] The 9,000-year history of village life in South Asia traces back to the Neolithic (7000–4300 BCE) site of Mehrgarh in Pakistan, [12] [13] [14] and the 5,000-year history of urban life in South Asia to the various sites of the Indus Valley Civilization, including Mohenjo Daro and Harappa. [15] [16]
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 ...
A secondary palate enables the animal to eat and breathe at the same time and is a sign of a more active, perhaps warm-blooded, way of life. [21] They had lost gastralia and, possibly, scales. 260-230 Ma Cynognathus. One subgroup of therapsids, the cynodonts, lose pineal eye and lumbar ribs and very likely became warm-blooded.
Earth is the only place in the universe known to harbor life, where it exists in myriad environments. [8] [9] The origin of life on Earth was at least 3.5 billion years ago, possibly as early as 3.8-4.1 billion years ago. [2] [3] [4] Since its emergence, life has persisted in several geological environments.
12 November: East Pakistan: The Bhola cyclone devastates East Pakistan and Eastern India, resulting in extreme loss of life. [ 105 ] 300,000 to 500,000 people are killed. 7 December: 1970 Pakistani general election were held on 7 December 1970, although the polls in East Pakistan, originally scheduled for October, were delayed by disastrous ...
Formerly dated to 15 kya, the date modern human presence in Tibet has been pushed back to at least 38 kya based on genetic evidence. Archaeological evidence from the bank of the Salween River in the southeastern Tibetan Plateau was dated between 32 and 39 kya. [48] [49] [50] Asia, South Asia: Sri Lanka: 34: Fa Hien Cave