scholarly journals Social behavior and feeding ability of two phenotypes of Gasterosteus aculeatus in relation to their spatial and trophic segregation in a temperate lake

1976 ◽  
Vol 54 (2) ◽  
pp. 107-121 ◽  
Author(s):  
Gary Lee Larson

Significant differences in morphology, behavior, spatial distribution, and feeding habits were found between limnetic and benthic forms of the threespine stickleback (Gasterosteus aculeatus) in a small British Columbia lake. The social behavior and feeding ability of each form were studied experimentally to provide a basis for determining the mechanisms of spatial and trophic segregation observed in the lake. The hypothesis that the benthic form was solitary, aggressive, and attracted to lake-bottom cover, and the limnetic form was gregarious, nonaggressive, and attracted to lake-surface cover was supported by the laboratory experiments. Furthermore, the hypothesis that the limnetic form could feed more successfully on zooplankton, and the benthic form on macrobenthos was supported by the experiments. The benthic form spent significantly more time in search of food in lake-bottom cover than did the limnetic form. It is suggested that the two forms of stickleback had undergone extensive adaptations to very different habitats in the lake, and therefore, their spatial and food segregation was not maintained entirely by interactions, but at least partially by inherent behavioral differences.

Behaviour ◽  
1973 ◽  
Vol 46 (3-4) ◽  
pp. 189-219 ◽  
Author(s):  
Sharon L. Smith ◽  
Elizabeth C. Oppenheimer ◽  
Jill G. De VILLA ◽  
W. John Smith ◽  
Frederick A. Ulmer

Abstract(I) A colony of black-tailed prairie dogs in the Philadelphia zoo is being used for long term studies of various aspects of social behavior including pattern of social organization, stylized means of communicating, and the effects of individual behavioral differences on communication and social structure. (2) This report deals with the annual cycle of social behavior manifested by the colony during the first three years of study. In gross outline an annual cycle can be described as follows: during the summer most individuals have "friendly" inter-relationships, and little organization is apparent. During autumn the animals gradually band into coterie groups and each group begins to defend a common territory, primarily through a highly ritualized procedure of "challenging" neighbors across a common boundary. By midwinter the adult males are very aggressive. With the advent of the winter breeding season, the females too become aggressive, and some establish territories that may subdivide coterie territories. In spring males and then females gradually become less aggressive, so that by about the time the pups emerge onto the surface the relaxed social relationships typical of summer are developing generally. (3) The shifting pattern of social organization is based on the division of individuals into classes on the basis of sex, age, dominance, and coterie and other bonds, and modified by the considerable inter-individual differencees in what may loosely be called "temperament." (4) Comparisons of the patterns of social organization shown by the zoo prairie dogs with those thus far described in the literature for wild populations show fundamental similarities, although the very high density and lack of opportunity for emigration in the zoo colony have lead to some modifications which are described and discussed. (5) The complexity of the social; organization of the black-tailed prairie dog is unusual for a rodent, and a model is proposed to account for its evolution from more widespread patterns of rodent social behavior. As the model emphasizes the role of the very open grassland habitat of the species in intensifying the natural selection potentially responsible for the evolution of this socal complexity, it suggests that habitat similarities may underlie evolutionary convergences in the social systems of black-tailed prairie dogs and savanna-dwelling primates.


2019 ◽  
Vol 60 (2) ◽  
pp. 303-305
Author(s):  
Valdir Leite da Silva ◽  
José Cândido ◽  
José Nelson Campanha ◽  
Doraci R. de Oliveira ◽  
Carla Gheler-Costa ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Renad Jabarin ◽  
Nina Levy ◽  
Yasmin Abergel ◽  
Joshua H. Berman ◽  
Amir Zag ◽  
...  

AbstractIn this study we tested the hypothesis that pharmacological modulation of glutamatergic neurotransmission could rescue behavioral deficits exhibited by mice carrying a specific mutation in the Iqsec2 gene. The IQSEC2 protein plays a key role in glutamatergic synapses and mutations in the IQSEC2 gene are a frequent cause of neurodevelopmental disorders. We have recently reported on the molecular pathophysiology of one such mutation A350V and demonstrated that this mutation downregulates AMPA type glutamatergic receptors (AMPAR) in A350V mice. Here we sought to identify behavioral deficits in A350V mice and hypothesized that we could rescue these deficits by PF-4778574, a positive AMPAR modulator. Using a battery of social behavioral tasks, we found that A350V Iqsec2 mice exhibit specific deficits in sex preference and emotional state preference behaviors as well as in vocalizations when encountering a female mouse. The social discrimination deficits, but not the impaired vocalization, were rescued with a single dose of PF-4778574. We conclude that social behavior deficits associated with the A350V Iqsec2 mutation may be rescued by enhancing AMPAR mediated synaptic transmission.


2021 ◽  
pp. 1-82
Author(s):  
Joseph Cesario

Abstract This article questions the widespread use of experimental social psychology to understand real-world group disparities. Standard experimental practice is to design studies in which participants make judgments of targets who vary only on the social categories to which they belong. This is typically done under simplified decision landscapes and with untrained decision makers. For example, to understand racial disparities in police shootings, researchers show pictures of armed and unarmed Black and White men to undergraduates and have them press "shoot" and "don't shoot" buttons. Having demonstrated categorical bias under these conditions, researchers then use such findings to claim that real-world disparities are also due to decision-maker bias. I describe three flaws inherent in this approach, flaws which undermine any direct contribution of experimental studies to explaining group disparities. First, the decision landscapes used in experimental studies lack crucial components present in actual decisions (Missing Information Flaw). Second, categorical effects in experimental studies are not interpreted in light of other effects on outcomes, including behavioral differences across groups (Missing Forces Flaw). Third, there is no systematic testing of whether the contingencies required to produce experimental effects are present in real-world decisions (Missing Contingencies Flaw). I apply this analysis to three research topics to illustrate the scope of the problem. I discuss how this research tradition has skewed our understanding of the human mind within and beyond the discipline and how results from experimental studies of bias are generally misunderstood. I conclude by arguing that the current research tradition should be abandoned.


1973 ◽  
Vol 36 (3) ◽  
pp. 735-738 ◽  
Author(s):  
Joaquin F. Sousa-Poza ◽  
Robert Rohrberg ◽  
Ernest Shulman

Some characteristics of the social behavior of field-dependents as well as their superior recognition of ambiguous social stimuli led to the hypothesis that they would show greater self-disclosure than field-independents. This hypothesis was tested by administering the 60-item Jourard Self-disclosure Questionnaire (JSDQ) to 13 field-dependent and 13 field-independent Ss. In terms of total self-disclosure scores, field-dependents showed significantly (.025) higher levels than field-independents. Results are discussed in light of personality theories which emphasize the role of self-conceptual transactions in the development of the self.


1989 ◽  
Vol 67 (6) ◽  
pp. 1599-1602 ◽  
Author(s):  
Vital Boulé ◽  
Gerard J. Fitzgerald

Female threespine sticklebacks (Gasterosteus aculeatus) spend only 9–15 days on the spawning grounds, an intertidal salt marsh at Isle Verte, Quebec, during a 2-month breeding season. Individuals average only one spawning. However, in the laboratory they lay clutches of several hundred eggs every 3–5 days for several months. We designed laboratory experiments to determine (i) whether daily temperature fluctuations similar to those encountered in the marsh affect reproduction (number of clutches, number of eggs per clutch, and size of eggs) and (ii) whether the amplitude of the fluctuations encountered by the fish affects reproduction. We compared the reproduction of females held in fluctuating temperatures with that of females kept at 20 °C. Fish kept under fluctuating conditions produced more eggs per clutch but had longer interspawning intervals than those at 20 °C. Total seasonal egg production and egg size did not differ between the two groups. Fish in fluctuating temperatures survived longer and were in better condition than those at 20 °C. We conclude that the amplitude of the fluctuations is less important than mean temperature in determining reproductive performance. Fluctuating temperatures on the spawning grounds are not responsible for the short residency there.


1959 ◽  
Vol 201 (4) ◽  
pp. 128-140 ◽  
Author(s):  
John A. King

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