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evolution |
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evolution /evo·lu·tion/ (ev″ah-loo´shun) a developmental process in which an organ or organism becomes more and more complex by differentiation of its parts; a continuous and progressive change according to certain laws and by means of resident forces. convergent evolution the appearance of similar forms and/or functions in two or more lines not sufficiently related phylogenetically to account for the similarity. organic evolution the origin and development of species; the theory that existing organisms are the result of descent with modification from those of past times.
evolution [ev′əlo̅o̅′shən] Etymology: L, evolvere, to roll forth 1 a gradual, orderly, and continuous process of change and development from one condition or state to another. It encompasses all aspects of life, including physical, psychologic, sociologic, cultural, and intellectual development, and involves a progressive advancement from a simple to a more complex form or state through the processes of modification, differentiation, and growth. 2 a change in the genetic composition of a population of organisms over time. 3 the appearance over long periods of time of new taxonomic groups of organisms from preexisting groups. Kinds of evolution are convergent evolution, determinant evolution, emergent evolution, organic evolution, orthogenic evolution, and saltatory evolution. evolutionist, n. evolution the process of development in which an organ or organism becomes more and more complex by the differentiation of its parts; a continuous and progressive change according to certain laws and by means of resident forces. convergent evolution the development, in animals that are only distantly related, of similar structures or functions in adaptation to similar environment. divergent evolution the development of different characteristics in animals that were closely related in response to being placed in different environments. Patient discussion about Evolutionary theorist. Q. How the bacterias are produced? A. The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals. (The name comes from the Greek bakterion, meaning small staff.) Bacteria are ubiquitous in every habitat on Earth, growing in soil, acidic hot springs, radioactive waste,[2] water, and deep in the Earth's crust, as well as in organic matter and the live bodies of plants and animals. There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water; in all, there are approximately five nonillion (5×1030) bacteria on Earth,[3] forming much of the world's biomass.[4] Bacteria are vital in recycling nutrients, with many important steps in nutrient cycles depending on these organisms, such as the fixation of nitrogen from the atmosphere and putrefaction. http://en.wikipedia.org/wiki/Bacteria Hope this helps. Read more or ask a question about Evolutionary theoristHow to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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Gould's primary academic focus was evolution, particularly his concept of punctuated equilibrium--now an influential viewpoint among evolutionary theorists. In the 1960s, evolutionary theorist George Williams argued that benefits to the group are too weak a force to be invoked as an evolutionary explanation. Of all the evolutionary theorists currently writing she is one of the principle voices arguing for empirical verification through detailed cross-cultural data sets. |
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