Search results
Results from the WOW.Com Content Network
History of Animals (Greek: Τῶν περὶ τὰ ζῷα ἱστοριῶν, Ton peri ta zoia historion, "Inquiries on Animals"; Latin: Historia Animalium, "History of Animals") is one of the major texts on biology by the ancient Greek philosopher Aristotle, who had studied at Plato's Academy in Athens. It was written in the fourth century BC ...
539 Ma – present. The Phanerozoic Eon (Greek: period of well-displayed life) marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, with major mass extinctions at division points.
The evolution of cetaceans is thought to have begun in the Indian subcontinent from even-toed ungulates (Artiodactyla) 50 million years ago (mya) and to have proceeded over a period of at least 15 million years. [2] Cetaceans are fully aquatic mammals belonging to the order Artiodactyla and branched off from other artiodactyls around 50 mya.
The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period. It includes brief explanations of the various taxonomic ranks in ...
Saber-toothed predator. From top and from left to right, Inostrancevia, Hoplophoneus, Barbourofelis, Smilodon, Machaeroides and Thylacosmilus. A saber-tooth (alternatively spelled sabre-tooth) is any member of various extinct groups of predatory therapsids, predominantly carnivoran mammals, that are characterized by long, curved saber -shaped ...
Tinbergen's four questions. Tinbergen's four questions, named after 20th century biologist Nikolaas Tinbergen, are complementary categories of explanations for animal behaviour. These are also commonly referred to as levels of analysis. [1] It suggests that an integrative understanding of behaviour must include ultimate (evolutionary ...
The Ediacaran (/ ˌiːdiˈækərən /; formerly Vendian) biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (c. 635–538.8 Mya). These were enigmatic tubular and frond-shaped, mostly sessile, organisms. [1][2] Trace fossils of these organisms have been found ...
e. Evidence of common descent of living organisms has been discovered by scientists researching in a variety of disciplines over many decades, demonstrating that all life on Earth comes from a single ancestor. This forms an important part of the evidence on which evolutionary theory rests, demonstrates that evolution does occur, and illustrates ...