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单词 mutation
释义 mutation|mjuːˈteɪʃən|
[a. F. mutacion (13th c. in Littré), -ation, ad. L. mūtātiōn-em, n. of action f. mūtāre to change: see mutate and -ation.]
1. a. The action or process of changing; alteration or change in form or qualities.
c1374Chaucer Boeth. Pr. vi. 18 (Camb. MS.), ffor-thi wenestow þat þise Mutacyouns of fortune fletyn with-owte gouernor.1426Lydg. De Guil. Pilgr. 3280 To maken..That merveyllous mutacion, Bred in-to flesshe, wyn in-to blood.c1430Pilgr. Lyf Manhode i. xli. (1869) 24 Al mutacioun that is doon in haste j hate.c1522Bp. Fox in Ellis Orig. Lett. Ser. ii. II. 4 Thestate & condicion of the Toune & Marches of Calis & other Fortryses within the same, & of theyr ruynes, decayes, mutacyons, and alteracions, fro the auncyent estatuz and ordinances [etc.].1523Ld. Berners Froiss. I. clv. 187 It is come to the kynges knowledge, howe that his subgettes ar sore greued by reason of the mutacyon of y⊇ moneys.1605Shakes. Lear iv. i. 11 O world! But that thy strange mutations make vs hate thee Life would not yeelde to age.1655G. S. in Hartlib Ref. Commw. Bees 21, I took the pain to observe and collect the Generation of several Insects, with their various mutations from kind to kind.1776Burney Hist. Mus. (1789) I. iv. 54 The Mutations or changes incident to melody which in modern music we should call..modulation.a1849Hor. Smith Addr. Mummy ix, Since first thy form was in this box extended We have above ground seen some strange mutations.1892Stevenson & L. Osbourne Wrecker vi, More than three years had intervened almost without mutation in that stationary household.
b. Changeableness. Obs.
a1548Hall Chron., Edw. IV (1550) 23 Suche is y⊇ mutacyon of the common people, lyke a rede wyth euery wind is agitable and flexible.
c. Change in government, revolution. Also, ? revolt, insurrection. Obs.
In the sense ‘revolt’ the word may be a. OF. meutacion, f. meute riot, uproar (see mute n.3).
a1470Tiptoft Cæsar x. (1530) 12 He douted lest in his absence there shuld arise some chaunge or mutacyon in Fraunce.1660Milton Free Commw. Wks. 1851 V. 432 We had bin then by this time firmly rooted past fear of Commotions or Mutations.1737Whiston Josephus, Hist. i. xvi. §5 He..exacted the tribute..as a penalty for the mutations they had made in the country.
2. concr. (Roman Antiq.) As rendering of L. mutatio (see quot. 1610). Obs.
1610Holland Camden's Brit. i. 65 Also Mutations; for so they called in that age, the places where strangers, as they journeied did change their post-horses [etc.].1677Plot Oxfordsh. 326 Pillars of stone, whereon they inscribed the distances from the regal Cities, Stations, and Mutations.
3. Mus.
a. In mediæval solmization: The change from one hexachord to another involving a change of the syllable applied to a given note.
1597Morley Introd. Mus. Annot., Mutation is the leauing of one name of a note and taking another in the same sound.1609Douland Ornith. Microl. 16 To a Musitian..Mutation is..the putting of one concord for another in the same Key.1760Phil. Trans. LI. 743 The author is speaking of the sixth division of harmonic, which was mutation.1807Robinson Archæol. Græca v. xxiii. 534 In music the Greeks distinguished..rhythmus, mutations, and melopœia.
b. mutation stop: a stop whose pipes produce tones one-fifth or a major third above the proper pitch of the key struck, or above one of its octaves. So mutation rank.
1855Hopkins Organ 110 Mutation or Filling-up Stops do not give a sound corresponding with the key pressed down; but some sound g on the C key, others e.1881C. A. Edwards Organs 153 The proper balancing of the foundation and mutation ranks.
c. In violin-playing: ‘The shifting of the hand from one position to another’ (Cent. Dict. 1890).
4. Gram.
a. In the Celtic languages, a change of an initial consonant, depending on the grammatical (or, prehistorically, on the phonetic) character of the preceding word.
1843Proc. Philol. Soc. I. 124 That remarkable system of initial mutations of consonants which distinguishes the Celtic languages from all others in Europe.1904Athenæum 5 Nov. 621/3 If Welsh loses its mutations as South Wales is doing slightly, we shall be sorry.
b. = umlaut.
1875–6H. Sweet in Trans. Philol. Soc. 558 The mutation of original ā, which is written æ in WS.Ibid. 567 The most marked distinction between A[nglo-] F[risian] and O[ld] S[axon] is the want of ‘umlaut’ or mutation in the latter.1887Skeat Princ. Eng. Etymol. Ser. i. 211 In many instances, the original vowel of the root has suffered both mutation and gradation.
Comb.1892Sweet Eng. Gramm. I. 315 The following mutation-plurals are still in common use.
5. Law.
a. In French law (see quot. 1856). Also Comb. (in Canada) mutation-fine.
1825Act 6 Geo. IV, c. 59 §5 Every..droit de lods et ventes, and mutation fine of every description [Lower Canada].1856Bouvier Amer. Law Dict. (ed. 6) II. 195 Mutation, French law... Applied to designate the change which takes place in the property of a thing in its transmission from one person to another... It is nearly synonymous with transfer.
b. mutation of libel (see quot. 1856).
1685Consett Pract. Spirit. Courts iii. i. §2 (1700) 82 We now come to the other part of Mynsinger his purpose (Scil.) the mutation or changing of Libels; mutare Libellum, to change the Libel, is to vary and alter the substance of it.1856Bouvier Amer. Law Dict. (ed. 6) II. 195 Mutation of libel, practice. An amendment allowed to a libel, by which there is an alteration of the substance of the libel.
6. Biol.
a. The process whereby detectable and heritable changes in genetic material arise; also, formerly, a process by which de Vries (Die Mutationstheorie (1901–3)) supposed a new species to be suddenly produced by a departure from the parent type (in contrast with variation).
b. A change of this kind in the genetic material.
c. An individual (or, more rarely, an assemblage of like individuals) which has been produced by this process; a mutant.
1894W. B. Scott in Amer. Jrnl. Sci. Nov. 372 Bateson's results..emphasize strongly the difference between variation and that steady advance along certain definite lines which Waagen called mutation.1901Jrnl. R. Microsc. Soc. 439 Quite distinct from these are those abrupt..variations..which sometimes occur, and of which de Vries records a remarkable instance in the genus Œnothera. For such variations de Vries proposes the term mutations.1904Westm. Gaz. 23 Apr. 12/3 It is with the origin of the minor species that the De Vries Mutation Theory is concerned.1905in Q. Jrnl. Geol. Soc. LXI. Proc. p. lxxiii, A mutation, in the palaeontological and original sense, may be defined as a contemporaneous assemblage of individuals united by specific identity of structure inter se, and by common descent from a known pre-existing species, from which they differ in some minute but constant character or characters.1907Athenæum 31 Aug. 242/1 The theory of mutation..assumes that a species has its birth, its lifetime, and its death, even as an individual, and that throughout its life it remains one and the same. By a mutation it does not change itself, but simply produces a new type. The mutation ‘is allied to its ancestor as a branch is to a tree’.1919Jrnl. Exper. Zool. XXVIII. 381 In our opinion, the attempted distinctions between ‘saltations’, ‘mutations’, and ‘variations of slight degree’ have led rather to confusion of thought than to clearer thinking. To us these are all a single class, ‘mutations’, and the term carries no restrictions of degree, covering the most extreme as well as the slightest detectable inherited variation.1925Genetics X. 117 If one thinks of mutations as being simply inherited changes, it becomes necessary to distinguish changes that involve whole chromosomes.., changes that involve several adjacent genes.., and what have been called ‘point-mutations’ or ‘gene-mutations’.1928,1930[see gene mutation s.v. gene1 2].1955Sci. News Let. 25 June 409 Many mutations are lethal. If man-made irradiation increases the mutation rate, the result is sure to be harmful.1955Sci. Amer. July 74/2 Reproduction is one of the two essential features of life. Mutation is the other.1957I. Asimov Naked Sun (1958) xi. 145 Even the best gene analysis of parents can't assure that all gene permutations and combinations will be favourable, to say nothing of the possibility of mutations. That's our big concern, the unexpected mutation.1965A. H. Sturtevant Hist. Genetics x. 62 It is ironic that few of the original mutations observed by de Vries in Oenothera would now be called mutations.1971J. Z. Young Introd. Study Man xxviii. 392 The cause of mutation is some faulty copying during replication of the DNA. This..will be inherited only if it occurs in the line of the germ cells. Mutations elsewhere in the body are called somatic mutations... The accumulation of somatic mutations may produce some of the diseases of old age.1972[see Mendelian n.].1974Sci. Amer. Sept. 82 (caption) One-gene mutation is responsible for the difference between the beta chain of a normal hemoglobin molecule..and that of hemoglobin S, the variant form responsible for sickle-cell anemia.
7. Special Comb.: mutation mink, a mink belonging to a mutant strain with a fur colour different from the normal; fur or a garment made from the skin of such a mink; mutation pressure, a tendency for recurring mutation (rather than selection) to alter the frequency of a particular allele within a population; mutation rate, the rate at which gene mutations occur (see quot. 1971); mutation theory, the theory of de Vries concerning the origin of new species (see 6 a).
1942H. Bock in Amer. Fur Breeder Oct. 14 (title) *Mutation mink and their use in coats.1945R. G. Hodgson Mink Book (ed. 2) 41 Mutation mink got their start in the United States..and the Silverblu..was the important mink to give the industry something to think about.1956J. G. Links Book of Fur 166 The mutation mink names Silverblu, Aleutian, Royal Pastel..each representing a different mutation which had been developed since the original Silverblu.1958Vogue Jan. 12 Natural pale beige mutation mink.1966R. Serjeant Mink on my Shoulder xi. 152 To the fur trade and perhaps also to the general public, the mutation mink means a mink of an abnormal colour or fur pattern that can be repeated at will.
1931Genetics XVI. 100 (heading) *Mutation pressure.1962D. J. Merrell Evol. & Genetics xxiv. 237 Theoretically mutation pressure alone could bring about evolution.
1930R. A. Fisher Genetical Theory Nat. Select. vi. 122 If..the *mutation rates..are high enough to maintain any considerable genetic diversity, it will only be the best adapted genotypes which can become the ancestors of future generations.1948Proc. R. Soc. B. CXXXV. 168 It follows that human mutation rates are about twice those of Drosophila per nuclear division, and about one two-hundredth of those of Drosophila per day.1971Levitan & Montagu Textbk. Human Genetics xvii. 649 Mutation rates are usually stated in terms of the number of changed genes per locus per generation.
1904*Mutation theory [see sense 6 above].1912Amer. Naturalist XLVI. 359 We can distinguish and trace the history of these quantitative variations from generation to generation only when the differences between them are of some size. This has led many to think that only variations of some size are inherited (the mutation theory) and others to deny that such variations can be increased in size by selection.1962D. J. Merrell Evol. & Genetics xxi. 213 In the very early days of genetics de Vries (1902) proposed the mutation theory of evolution as an alternative to the theory of natural selection.
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