evolution

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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

(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.

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.

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.

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References in periodicals archive ?
Adaptive change in Charles Darwin's theory of evolution occurs over successive generations.
It is simple enough to be understood by the dullest chemistry student, it does not require any complicated tables of values determined through painstaking observation, it is broadly applicable to the phenomenon it seeks to explain, and its theoretical foundation is so apparently plausible that many are likely to have remarked of VSEPR theory as Thomas Huxley did of Darwin's theory of evolution: "Why didn't I think of that?"'
Which in turn adds to Darwin's theory of evolution: little finch, tiny snail, brilliantly designed by no one.
CHARLES Darwin's theory of evolution struck at the heart of the Christian belief that God - a supernatural being - created all life as we see it today.
Joseph University, Kaslik, Jesuit University, Lady of Loueizy, La Sagesse and Antonine University in conjunction with the International Center for Cultural Dialogue and Getting Togetherness "Faith and Sciences" on the 150th jubilee of Darwin's theory of evolution and the 400th birthday of Galileo
According to Darwin's theory of evolution, sheep would become larger over time, since size offers a competitive advantage against the cold.
IDA, a 47-million-year-old fossil, has been acclaimed as a missing link in the Tree of Life that proves Darwin's Theory of Evolution.
BILL HAYES, Marton DARWIN'S theory of evolution remains just a theory.
Can Darwin's theory of evolution and natural selection be true?
The heavyweight bout was probably T.H Huxley v Bishop Wilberforce slugging it out over Darwin's theory of evolution in 1860.