When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. History of life - Wikipedia

    en.wikipedia.org/wiki/History_of_life

    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 ...

  3. Timeline of the evolutionary history of life - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the...

    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.

  4. History of Earth - Wikipedia

    en.wikipedia.org/wiki/History_of_Earth

    The Paleozoic ("old life") era was the first and longest era of the Phanerozoic eon, lasting from 538.8 to 251.9 Ma. [105] During the Paleozoic, many modern groups of life came into existence. Life colonized the land, first plants, then animals. Two significant extinctions occurred.

  5. File:Original stories from real life 1796.pdf - Wikipedia

    en.wikipedia.org/wiki/File:Original_stories_from...

    The following other wikis use this file: Usage on en.wikisource.org Index:Original stories from real life 1796.pdf; Page:Original stories from real life 1796.pdf/1

  6. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    Early micro-fossils may have come from a hot world of gases such as methane, ammonia, carbon dioxide, and hydrogen sulfide, toxic to much current life. [230] Analysis of the tree of life places thermophilic and hyperthermophilic bacteria and archaea closest to the root, suggesting that life may have evolved in a hot environment. [ 231 ]

  7. Spontaneous generation - Wikipedia

    en.wikipedia.org/wiki/Spontaneous_generation

    Pier Antonio Micheli, c. 1729, observed that when fungal spores were placed on slices of melon, the same type of fungi were produced that the spores came from, and from this observation he noted that fungi did not arise from spontaneous generation. [42] In 1745, John Needham performed a series of experiments on boiled broths. Believing that ...

  8. Human evolution - Wikipedia

    en.wikipedia.org/wiki/Human_evolution

    The hominoids are descendants of a common ancestor.. Homo sapiens is a distinct species of the hominid family of primates, which also includes all the great apes. [1] Over their evolutionary history, humans gradually developed traits such as bipedalism, dexterity, and complex language, [2] as well as interbreeding with other hominins (a tribe of the African hominid subfamily), [3] indicating ...

  9. Existence - Wikipedia

    en.wikipedia.org/wiki/Existence

    Existence sets real entities apart from imaginary ones, [2] and can refer both to individual entities or to the totality of reality. [3] The word "existence" entered the English language in the late 14th century from old French and has its roots in the medieval Latin term ex(s)istere, which means "to stand forth", "to appear", and "to arise". [4]