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2. 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.

3. 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 ...

4. Life: A Natural History of the First Four Billion Years of ...

   en.wikipedia.org/wiki/Life:_A_Natural_History_of...

   Fortey used this book to explain how life has evolved over the last four billion years. He discusses evolution, biology, the origin of life, and paleontology. Under its various titles Fortey's book has become a best-seller; according to WorldCat , it is in over a thousand public libraries in the United States alone.

5. Abiogenesis - Wikipedia

   en.wikipedia.org/wiki/Abiogenesis

   Starting in 1985, researchers proposed that life arose at hydrothermal vents, [237] [238] that spontaneous chemistry in the Earth's crust driven by rock–water interactions at disequilibrium thermodynamically underpinned life's origin [239] [240] and that the founding lineages of the archaea and bacteria were H 2-dependent autotrophs that used ...

6. Earliest known life forms - Wikipedia

   en.wikipedia.org/wiki/Earliest_known_life_forms

   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 ...

7. Biology - Wikipedia

   en.wikipedia.org/wiki/Biology

   Biology is the scientific study of life. [1] [2] [3] It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. [1] [2] [3] For instance, all organisms are composed of at least one cell that processes hereditary information encoded in genes, which

8. Introduction to evolution - Wikipedia

   en.wikipedia.org/wiki/Introduction_to_evolution

   The age of the Earth is about 4.5 billion years. [1] [2] [3] The earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago. [4] [5] [6] Evolution does not attempt to explain the origin of life (covered instead by abiogenesis), but it does explain how early lifeforms evolved into the complex ecosystem that we see ...

9. Biogeographic realm - Wikipedia

   en.wikipedia.org/wiki/Biogeographic_realm

   The realms delineate large areas of Earth's surface within which organisms have evolved in relative isolation over long periods of time, separated by geographic features, such as oceans, broad deserts, or high mountain ranges, that constitute natural barriers to migration. As such, biogeographic realm designations are used to indicate general ...