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  2. Timeline of the evolutionary history of life - Wikipedia

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

    The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites

  3. History of Animals - Wikipedia

    en.wikipedia.org/wiki/History_of_Animals

    The History of Animals contains a large number of eye-witness observations, in particular of marine biology, in sharp contrast to Plato's "symbolic zoology". Aristotle's style and precision can be seen in the passage where he discusses the behaviour and anatomy of the cephalopods, mentioning the use of ink against predators , camouflage , and ...

  4. 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 ...

  5. Timeline of zoology - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_zoology

    This was the last major animal to be tamed as a source of milk, meat, power, and leather in the Old World. Lascaux aurochs, Stone Age [2] 3500 BC. Sumerian animal-drawn wheeled vehicles and plows were developed in Mesopotamia, the region called the "Fertile Crescent." Irrigation was probably done using animal power.

  6. Tree of life (biology) - Wikipedia

    en.wikipedia.org/wiki/Tree_of_life_(biology)

    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 ...

  7. History of zoology (1859–present) - Wikipedia

    en.wikipedia.org/wiki/History_of_zoology_(1859...

    This article considers the history of zoology since the theory of evolution by natural selection proposed by Charles Darwin in 1859. Charles Darwin gave new direction to morphology and physiology , by uniting them in a common biological theory: the theory of organic evolution.

  8. Evolution of mammals - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_mammals

    Figure 1:In mammals, the quadrate and articular bones are small and part of the middle ear; the lower jaw consists only of dentary bone.. While living mammal species can be identified by the presence of milk-producing mammary glands in the females, other features are required when classifying fossils, because mammary glands and other soft-tissue features are not visible in fossils.

  9. Animal - Wikipedia

    en.wikipedia.org/wiki/Animal

    The word animal comes from the Latin noun animal of the same meaning, which is itself derived from Latin animalis 'having breath or soul'. [6] The biological definition includes all members of the kingdom Animalia. [7] In colloquial usage, the term animal is often used to refer only to nonhuman animals.