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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
The History of Animals contains many accurate eye-witness observations, in particular of the marine biology around the island of Lesbos, such as that the octopus had colour-changing abilities and a sperm-transferring tentacle, that the young of a dogfish grow inside their mother's body, or that the male of a river catfish guards the eggs after ...
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 ...
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 ...
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.
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.
It also reduced CO 2 and oxidized H 2 (methanogenesis or acetogenesis) via acetyl-thioesters. [24] [25] By phylogenetic bracketing, analysis of the presumed LUCA's offspring groups, LUCA appears to have been a small, single-celled organism. It likely had a ring-shaped coil of DNA floating freely within the cell. Morphologically, it would likely ...
During this time, animals became bilateral and along with increasing complexity. [11] Many animals during this time fit into the annelid, arthropod, echinoderm, and cnidarian phyla. [11] Animals at this time developed bilateral symmetry with a clear anterior and posterior side, which included species like Spriggina, Charniodiscus and Yorgia. [10]