Comparative Ultrastructure and Systematics of the Colpodida (Ciliophora): Structural Differentiation in the Cortex of Colpoda simulans

1976 ◽  
Vol 95 (4) ◽  
pp. 581 ◽  
Author(s):  
Denis H. Lynn
Keyword(s):  
Structural Differentiation ◽  
Ultrastructure And Systematics ◽  
Comparative Ultrastructure

Comparative ultrastructure and systematics of the Colpodida. An ultrastructural description of Colpoda maupasi Enriquez, 1908

1976 ◽  
Vol 54 (3) ◽  
pp. 405-420 ◽  
Author(s):  
Denis H. Lynn
Keyword(s):  
Structural Variation ◽  
Ciliated Protozoa ◽  
Biological Organization ◽  
Present Scheme ◽  
Ultrastructure And Systematics ◽  
Different Levels ◽  
Comparative Ultrastructure

Structural variation at different levels of biological organization is considered important to the systematics of ciliated protozoa. Analysis of the ultrastructural literature on ciliates led to the structural-conservatism hypothesis, which has been formulated to account for the variation of ultrastructural components, primarily microtubular, in the cortex of diverse ciliate genera. The hypothesis proposes that the conservation of structure through time is inversely related lo the level of biological organization. This study presents a light microscopic and ultrastructural description of Colpoda maupasi Enriquez, 1908. Comparison of C. maupasi with other species of the Colpodida supports the structural-conservatism hypothesis. With this hypothesis, several relational inconsistencies are demonstrated in the present scheme of classification of the ciliates.

The Intertwined Histories of Personality and Social Psychology

2018 ◽  
pp. 10-34
Author(s):  
Thomas F. Pettigrew
Keyword(s):  
Social Psychology ◽  
World War I ◽  
Bounded Rationality ◽  
World War ◽  
Structural Differentiation ◽  
Interaction Models

Personality and social psychology histories have been closely intertwined for more than a century. Several critical differences have at times acted to separate the fields. One such divergence involved their models of humans—whether largely irrational (personality emphasis) or largely rational (social emphasis). This difference has subsided with their joint acceptance of a “bounded rationality.” More important has been their difference in focus—the microlevel of the person versus the mesolevel of the group and situation. Now, both fields largely agree on a variety of interaction models that include both the person and the situation. We trace these tensions between the two fields across eras: (a) origins through World War I (1890–1919); (b) early developments (1920–1935); (c) war influences (1936–1950); (d) structural differentiation and slow acceptance (1951–1965); (e) dual crises (1966–1985); (f) coming back together again (1986–2000); and (7) continued fusion (2001–present).

scholarly journals Structural comparison of the rostra of two species of weevils coexisting on Ailanthus altissima: the response to ecological demands of egg deposition

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ganyu Zhang ◽  
Wenjuan Guo ◽  
Xiaoyi Wang ◽  
Qian Wang ◽  
Jin Cui ◽  
...  
Keyword(s):  
Adaptive Radiation ◽  
Egg Laying ◽  
Ailanthus Altissima ◽  
Structural Comparison ◽  
Structural Differentiation ◽  
Functional Potential ◽  
Egg Deposition ◽  
Adductor Muscles ◽  
Structural Differences ◽  
Oviposition Sites

Abstract Background Elongated rostra play an important role in the egg-laying of weevils, and its emergence plays a key role in the adaptive radiation of weevils. Eucryptorrhynchus scrobiculatus Motschulsky and E. brandti Harold co-occur on the same only host Ailanthus altissima, while their oviposition sites are different. In order to understand the adaptation between the rostra of the two weevils and their oviposition sites, the structural differentiation of the rostra in E. scrobiculatus and E. brandti was compared. Results The present study reveals that: (1) The rostra length of E. scrobiculatus and E. brandti was found to be correlated with body size, larger weevils have a correspondingly longer rostrum. The increase of rostra length may be a byproduct of larger weevils. (2) There were significant differences in the external shape of the two rostra, especially the shape of the mandibles of the mouthparts at the apex of the rostra used to excavate an oviposition cavity. (3) There was no difference in the size of the abductor muscles that control the extension of the mandibles, but there were significant differences in the size of the adductor muscles that control the contraction of the mandibles. Conclusions These structural differences reflect the functional potential ovipositional tactics of rostra, which is considered to be a response to the ecological demands of egg deposition, and also provide new insights into the coexistence of two weevil species in the same host A. altissima.

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