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  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 ...

  3. Life - Wikipedia

    en.wikipedia.org/wiki/Life

    Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from matter that does not. It is defined descriptively by the capacity for homeostasis, organisation, metabolism, growth, adaptation, response to stimuli, and reproduction. All life over time eventually reaches a state of ...

  4. Earliest known life forms - Wikipedia

    en.wikipedia.org/wiki/Earliest_known_life_forms

    Earliest known life forms. 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 old (or Ga) according to biologically fractionated graphite inside a single zircon grain in the Jack Hills range of Australia. [2] The ...

  5. Early life - Wikipedia

    en.wikipedia.org/wiki/Early_life

    Zygote, at the start of an organism's life; Embryo, early in an organism's life; Foetus, early in an animal's life, occurring before birth; Larva, an early stage in many animal life forms before maturity; Child, early human life

  6. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    NASA's 2015 strategy for astrobiology aimed to solve the puzzle of the origin of life – how a fully functioning living system could emerge from non-living components – through research on the prebiotic origin of life's chemicals, both in space and on planets, as well as the functioning of early biomolecules to catalyse reactions and support inheritance.

  7. Timeline of the evolutionary history of life - Wikipedia

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

    The timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. Dates in this article are consensus estimates based on scientific evidence, mainly fossils . In biology, evolution is any change across successive generations in the heritable ...

  8. Charles Darwin - Wikipedia

    en.wikipedia.org/wiki/Charles_Darwin

    Charles Robert Darwin FRS FRGS FLS FZS JP [5] ( / ˈdɑːrwɪn / [6] DAR-win; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, [7] widely known for his contributions to evolutionary biology. His proposition that all species of life have descended from a common ancestor is now generally accepted and ...

  9. Meaning of life - Wikipedia

    en.wikipedia.org/wiki/Meaning_of_life

    The meaning of life pertains to the inherent significance or philosophical meaning of living (or existence in general). There is not a definitive answer, and thinking or discourse on the topic is sought in the English language through the question, "What is the meaning of life?"