atavism


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atavism

(ăt`əvizəm), the appearance in an individual of a characteristic not apparent in the preceding generation. At one time it was believed that such a phenomenon was thought to be a reversion of "throwback" to a hypothetical ancestral prototype. The term is seldom used today since science has shown that such abnormal characteristics can be explained by the inheritance of a pair of recessive genesgene,
the structural unit of inheritance in living organisms. A gene is, in essence, a segment of DNA that has a particular purpose, i.e., that codes for (contains the chemical information necessary for the creation of) a specific enzyme or other protein.
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. See MendelMendel, Gregor Johann
, 1822–84, Austrian monk noted for his experimental work on heredity. He entered the Augustinian monastery in Brno in 1843, taught at a local secondary school, and carried out independent scientific investigations on garden peas and other plants until
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.

Atavism

 

the appearance in organisms of features that are absent in their immediate ancestors but which did exist in very distant ancestors. An example of atavism could be the development of a caudal appendage in man, the appearance of two extra toes along the sides of the completely developed middle toe of the horse, or the development of pinnately compound leaves instead of phyllodes in the green wattle. Since to a certain degree individuals repeat the organizational features of their ancestors in the developmental process, a disturbance of normal development can lead to a situation in which the adult organism keeps for its entire life the ancestral features which normally appear in the embryo and usually disappear in the course of further development. An example of such atavism would be the appearance in man of a cervical fistula reminiscent of the gill slit of his mammalian ancestors, the fishes and amphibians. Polymastia in man (the formation of a larger than normal number of pairs of mammary glands), tridactylism in horses, and so forth, are also related to atavism. Atavism also includes the occurrence of features from distant ancestors in the regeneration of organs. In this instance, the organs regenerate with the features characteristic of the more ancient forms. Thus, in the regeneration of a lizard’s tail, the scale rings are sometimes formed in a more primitive shape. Upon regeneration of the anterior end of the body in certain annelids, head appendages are formed which are missing in the given form but which are inherent in its ancestors.

REFERENCE

Shimkevich, V. M. Biologicheskie osnovy zoologii. 5th ed., vols. 1–2. Moscow-Leningrad, 1923–25.

M. A. VORONTSOVA

atavism

[′ad·ə‚viz·əm]
(evolution)
Appearance of a distant ancestral form of an organism or one of its parts due to reactivation of ancestral genes.

atavism

the recurrence in a plant or animal of certain primitive characteristics that were present in an ancestor but have not occurred in intermediate generations
References in periodicals archive ?
In her third chapter, Seitler turns to the literary text to more fully flesh out the ways in which writers translate visual notions of atavism back into linguistic representations of such questions.
Indeed, Resu's fear of man's latent atavism seems to be borne out by the example of Furtivo, whose character has been vitiated and aninzalized by predatory lusts.
And perhaps Bram Stoker's Dracula (1897), almost despite itself, provides an appropriate model for this possibility of change, for, although recent literary criticism and indeed the novel itself have been keen to draw attention to the Count's atavism, his `child brain', and his `imperfectly formed mind' (21) that make him, as Van Helsing suggests, immediately recognizable to Max Nordau, the author of Degeneration, and Cesare Lombroso, the popularizer of criminal anthropology, as an atavistic case of arrested development, the novel also makes it very plain that over time this child-brain will develop and, indeed, has been developing into something much more significant and much harder to conquer.
Finally, if "Melanctha" provided Larsen with a foil for constructing Helga as a psychological subject, it was to Stribling's narrative that she turned to explore the tragic mulatto tradition's obsession with atavism through the trope of the birthright.
Their dancing in this well-crafted duet about atavism and evolution was brilliantly animalistic and acutely mutually attuned.
But Watson rightly points out that it was not at all a matter of Hibernian atavism.
Kolko, writing as the century nears its end, emphasizes the need for an historical approach because "the emergence of virulent nationalisms and ethnic turmoil make it imperative that we begin to diagnose our times far more profoundly lest the dragons of atavism and nationality once again wreak havoc on more and more of mankind.
Among the recreated odors A perfume arriving from some Distant atavism Will cause scenery like a dream to rise in the old-fashioned lighting Disconnected from anything real In which a girl a boy To judge from their costumes Are rolling on an abandoned scarf Searching for the trace the sweat the musk The passing of someone else Lover brother sister Themselves Their reason for being Their death.
This digital slide show (which was produced in collaboration with artist Andy Sharp of the musical and literary collective English Heretic) featured views of windswept coasts, a sunset over a silhouetted countryside, a rock cave, and much else that offered a glimpse of a disfigured naturalistic atavism.
Segregation or preference bestowed upon Ultra-Orthodox Jews was neither a new phenomenon nor an atavism in Israel.
Some of the excellent recent work on turn-of-the-century American narrative and science--work by Jennifer Fleissner, Daylanne English, Dana Seitler, and Jane Thraillkill--is absent, even though these scholars address issues (the gendered stalling of naturalist temporality, the long shadow cast by eugenic thought on fiction of the period, the recursive temporal subjectivity of atavism, and the relationship between realism, affect, and embodiment, respectively) that bear directly on some of Thurtle's claims.