evolution


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Related to evolution: theory of evolution, Evolution of Man

evolution

 [ev″o-lu´shun]
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 environments.

ev·o·lu·tion

(ev'ō-lū'shŭn),
1. A continuing process of change from one state, condition, or form to another.
2. A progressive distancing between the genotype and the phenotype in a line of descent.
3. The liberation of a gas or heat in the course of a chemical or enzymatic reaction.
[L. e-volvo, pp. -volutus, to roll out]

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

(ĕv′ə-lo͞o′shən, ē′və-)
n.
1. A continuing process of change from one state, condition, or form to another.
2. Change in the genetic composition of a population during successive generations, often resulting in the development of new species. The mechanisms of evolution include natural selection acting on the genetic variation among individuals, mutation, migration, and genetic drift.

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, psychological, sociological, 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.

ev·o·lu·tion

(ev'ŏ-lū'shŭn)
1. A continuing process of change from one state, condition, or form to another.
2. A progressive distancing between the genotype and the phenotype in a line of descent.
[L. e-volvo, pp. -volutus, to roll out]

evolution

The theory that all living organisms have developed in complexity, from a simple life form. Evolution occurs by the natural selection of those who, by the fortune of spontaneous random changes (mutations), happen to be best suited to their contemporary environment, to survive and reproduce. It does not occur by the passing on to offspring of characteristics acquired during the lifetime of an individual. Characteristics are passed on by the transmission of DNA from parents to offspring and, unless mutation has occurred, this DNA is an identical copy of the DNA of preceding generations.

evolution

an explanation of the way in which present-day organisms have been produced, involving changes taking place in the genetic make-up of populations that have been passed on to successive generations. According to DARWINISM, evolutionary MUTATIONS have given rise to changes that have, through NATURAL SELECTION, either survived in better adapted organisms (see ADAPTATION, GENETIC), or died out. Evolution is now generally accepted as the means which gives rise to new species (as opposed to SPECIAL CREATION) but there is still debate about exactly how it has taken place and how rapidly changes can take place. See LAMARCKISM.

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 evolution

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.

More discussions about evolution
References in periodicals archive ?
Lunetta, who holds a master's degree in chemistry, said even with his decades of work in the science field he cannot accept the theory of evolution as accurate.
It is true that evolution is incompatible with some Christian interpretations, but it is not incompatible with all.
FAVORITE TARGET Evolution is the biological process by which populations of organisms acquire new, advantageous traits, pass them on to subsequent generations, and sometimes create new species.
The theory of evolution will not seem acceptable to you whenever it is not decisively in accord with the immediate creation of each and every human soul by God, and whenever it does not regard as decisively important for the fate of mankind the disobedience of Adam, the universal first parent.
Just before school opened this year, the Kansas Board of Education voted to delete any mention of the theory of evolution from the state's science curriculum.
Not every controversy over teaching evolution in the public schools becomes as famous as Dover's, which ultimately resulted in a major lawsuit (Kitzmiller v.
The controversy surrounding evolution, and those like Anderson who refute it, is rooted in convictions.
The Cobb County school system is the second largest public school district in Georgia, but in 2002, the board of education surrendered to a religious pressure campaign and announced its plan to warn students that evolution is "a theory, not a fact" and that it should be "critically considered.
But it emphasizes the idea that evolution is a "theory," not a "fact," and should be scrutinized as such.
First of all, let me say at the beginning that I have studied not only physics but also geology and paleontology at Harvard, and so it is with this background that I reject the ordinary understanding of the Darwinian theory of evolution even on scientific grounds.
The 14 chapters are grouped into 3 broad sections: general concepts in microbial evolution, environment and the evolution of microbial pathogens, and the evolution of selected pathogenic species and mechanisms.