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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 .
A life form (also spelled life-form or lifeform) is an entity that is living, [1] [2] such as plants , animals , and fungi . It is estimated that more than 99% of all species that ever existed on Earth, amounting to over five billion species, [3] are extinct. [4] [5] Earth is the only celestial body known to harbor life forms. No form of ...
Edward Hitchcock's fold-out paleontological chart in his 1840 Elementary Geology. Although tree-like diagrams have long been used to organise knowledge, and although branching diagrams known as claves ("keys") were omnipresent in eighteenth-century natural history, it appears that the earliest tree diagram of natural order was the 1801 "Arbre botanique" (Botanical Tree) of the French ...
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 (or Ga) according to biologically fractionated graphite inside a single zircon grain in the Jack Hills range of Australia. [2]
A team of international researchers has challenged the long-held belief that complex life forms first emerged on Earth 635 million years ago, presenting findings that show life may have existed ...
The therapsids had temporal fenestrae larger and more mammal-like than pelycosaurs, their teeth showed more serial differentiation, their gait was semi-erect and later forms had evolved a secondary palate. 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 ...
Date/Time Thumbnail Dimensions User Comment; current: 03:50, 24 October 2018: 905 × 701 (732 KB): Nesnad: oops: 03:48, 24 October 2018: 905 × 701 (732 KB): Nesnad: Trying to correct the three errors pointed out in the image notes
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 ...