Results 71 to 80 of about 140 (95)

Evidence that gastropod torsion is driven by asymmetric cell proliferation activated by TGF-β signalling

Evidence that gastropod torsion is driven by asymmetric cell proliferation activated by TGF-β signalling
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The Adaptive Significance of Gastropod Torsion

Evolution, 1966
Unique among mollusks, the Gastropoda are characterized by a curious asymmetry, resulting from a rotation of the visceral hump and shell. Thus in the earlier stages of their embryonic development, gastropods have the same arrangement of parts as other mollusks, with the rudiments of the mantle cavity, gills, coelomic ducts, and associated structures at
Michael T. Ghiselin
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Larval Muscle Contraction Fails to Produce Torsion in a Trochoidean Gastropod

The Biological Bulletin, 2001
The causes and effects of ontogenetic torsion in gastropods have been debated intensely for more than a century (1-19). Occurring rapidly and very early in development, torsion figures prominently in shaping both the larval and adult body plans. We show that mechanical explanations of the ontogenetic event that invoke contraction of larval retractor ...
Michael G. Hadfield, Carole S. Hickman
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Muscle morphogenesis in primitive gastropods and its relation to torsion

Proceedings of the Zoological Society of London, 1955
SSummaryInHaliotis tuberculata, Patella vulgata and Patina pellucidathe young are hatched at an early trochophore stage and remain only a few days in the plankton, but inCalliostoma zizyphinumthe whole of this phase takes place within the egg membranes and the larva is plantigrade from the time of hatching.In all four genera the larval retractor muscle
Doris R. Crofts
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Gastropod ontogenetic torsion: Developmental remnants of an ancient evolutionary change in body plan

Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, 2003
AbstractA dramatic morphogenetic movement (‘ontogenetic torsion’) during the development of gastropods has been proposed as a recapitulation of the original developmental departure that established the novel gastropod body plan. Nevertheless, speculative literature about ontogenetic torsion and its evolutionary significance has far outstripped ...
Louise R. Page
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Ontogenetic torsion in two basal gastropods occurs without shell attachments for larval retractor muscles

Evolution & Development, 2002
SUMMARY Results of this study on two species of vetigastropods contradict the long‐standing hypothesis, originally proposed by Garstang (1929), that the larval retractor muscles power the morphogenetic movement of ontogenetic torsion in all basal gastropods.
Louise R. Page
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Spawning, larval development and settlement behaviour of Gibbula cineraria (Gastropoda: Prosobranchia) with a reappraisal of torsion in gastropods

Marine Biology, 1972
Cultures of developing larvae of Gibbula cineraria (L.) were obtained from adults spawning in the laboratory, and these cultures were reared to settlement of the larvae at 9 days. Dispersal of the outer jelly coat of the egg appeared to be delayed in the presence of spermatozoa.
A.J. Underwood
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GARSTANG'S HYPOTHESIS AND GASTROPOD TORSION

Journal of Molluscan Studies, 1987
C. B. Goodhart
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Gastropod torsion: predation and the opercular imperative

Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 1982
Steven Stanley
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