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Dominance Relationships (dominance + relationships)

Distribution by Scientific Domains

Life Sciences	80%

Selected Abstracts

Dominance relationships among one-male units in a provisioned free-ranging band of the Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains, China

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2008
Peng Zhang
Abstract We studied the dominance relationships among one-male units (OMUs) in a provisioned free-ranging band of the Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains of central China from 2001 to 2005. The band was composed of 6,8 OMUs that stayed in the band for several years. Linear dominance orders could be detected using displacement interactions with directional asymmetry among OMUs in 82.3±5% of interactions, and ambiguous and reversed interactions in 17.7±5%. The dominance rank of OMUs was positively related with the duration of their stay in the band, and this may be attributed to the association of the resident male with adult females, rather than the fighting ability of resident males, as males do not fight seriously with each other. Subordinate units were observed to merge with dominant units resulting in an elevation of their rank order. The linear dominance relationship among OMUs in the Sichuan snub-nosed monkeys may have evolved as a result of competition for preferred food trees. Am. J. Primatol. 70:634,641, 2008. © 2008 Wiley-Liss, Inc. [source]

Memory of Social Partners in Hermit Crab Dominance

ETHOLOGY, Issue 3 2005
Francesca Gherardi
We investigated the possibility that invertebrates recognize conspecific individuals by studying dominance relationships in the long-clawed hermit crab, Pagurus longicarpus. We conducted three sets of laboratory experiments to define the time limits for acquiring and maintaining memory of an individual opponent. The results reveal two characteristics that make individual recognition in this species different from standard associative learning tasks. Firstly, crabs do not require training over many repeated trials; rather, they show evidence of recognition after a single 30-min exposure to a stimulus animal. Secondly, memory lasts for up to 4 d of isolation without reinforcement. A third interesting feature of individual recognition in this species is that familiar opponents are recognized even before the formation of a stable hierarchical rank. That is, recognition seems to be relatively independent of repeated wins (rewards) or losses (punishments) in a dominance hierarchy. The experimental protocol allowed us to show that this species is able to classify conspecifics into two ,heterogeneous subgroups', i.e. familiar vs. unfamiliar individuals, but not to discriminate one individual of a group from every other conspecific from ,a unique set of cues defining that individual'. In other words, we demonstrated a ,binary', and not a ,true', individual recognition. However, 1 d of interactions with different crabs did not erase the memory of a former rival, suggesting that P. longicarpus uses a system of social partner discrimination more refined than previously shown. [source]

Age-Related Microhabitat Segregation in Willow Tit Parus montanus Winter Flocks

ETHOLOGY, Issue 11 2000
Lluís Brotons
It is expected that through flexibility in behaviour, flock living birds respond to the asymmetries in resource access derived from dominance relationships. We analysed the microhabitat use of willow tits in winter flocks and assessed possible factors which shape habitat segregation between adults and juveniles in different temperature regimes. When foraging in mild conditions (ambient temperature >,0°C), flocks split up into subgroups with adults foraging in inner parts of trees more often than juveniles. However, no differences were recorded in the vertical position occupied in trees. In harsh conditions (< , 4°C), flocks re-united and juveniles further moved to outer parts of trees, increasing horizontal segregation between age classes. In mild conditions, vigilance behaviour was not related to the position of birds in trees, but in harsh conditions, scanning frequency was higher in outer parts of trees only for adults. In mild weather, juvenile position in trees was associated with body size and mass. The foraging microhabitat segregation detected in harsh conditions fits the age-related hoarding distribution previously described in the same population. This supports the hypothesis that hoarded food is important in determining future foraging habitat use. Adult preference and intraspecific competition for safer or richer inner parts of trees as foraging sites during harsh conditions seems to determine the habitat segregation between adults and juveniles. Furthermore, we suggest that in mild weather, when foraging in the absence of adults, juveniles balance the costs of using a potentially dangerous microhabitat with the benefits of building energetically cheap and large food reserves through hoarding. The expected patterns of microhabitat segregation may differ in parids, depending on whether predation risk or other factors such as food availability are the main factors controlling habitat quality. [source]

International value versus growth: evidence from stochastic dominance analysis

INTERNATIONAL JOURNAL OF FINANCE & ECONOMICS, Issue 3 2009
Abhay Abhyankar
Abstract We investigate the value versus growth investment strategies from the perspective of stochastic dominance analysis. Using G7 country data on value and growth stocks, we find that value stocks stochastically dominate growth stocks only for the US, Canada, and Japan, while there are no significant stochastic dominance relationships between value and growth portfolios for the UK, France, Germany, and Italy. Our results imply that the value premium may be country and sample specific. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Absence of a dominance hierarchy confirms territorial organization in male bushbuck (Tragelaphus scriptus Pallas, 1766)

AFRICAN JOURNAL OF ECOLOGY, Issue 3 2009
Torsten Wronski
Abstract It has been suggested that all species of spiral-horned antelopes (Tragelaphini) lack territoriality. Furthermore, some authors suggested that bushbuck (Tragelpahus scriptus) males form dominance hierarchies. In this study, we investigated the dominance relationships in two groups of free-ranging bushbuck males in Queen Elizabeth National Park, Uganda. Adult males dominated young-adult bachelors and subadult males, but no distinct dominance relationships were found among adult males. Landau,s index of linearity revealed no linear dominance hierarchy in the study populations. Our results support the idea that adult males are territorial, and overt aggression is directed almost exclusively towards bachelors that challenge territory holders. Résumé On a suggéré que toutes les espèces d'antilopes à cornes spiralées (Tragelaphineae) ne montraient pas de territorialité. Qui plus est, certains auteurs ont suggéré que les mâles Guib harnaché (Tragelaphus scriptus) formaient des hiérarchies par dominance. Dans cette étude, nous avons cherché les relations de dominance dans deux groupes de mâles Guib harnaché vivant en liberté dans le Parc National Queen Elizabeth, en Ouganda. Les mâles adultes dominaient les jeunes mâles célibataires et les mâles sub-adultes, mais on n'a trouvé aucune relation de dominance distincte entre les mâles adultes. L'index de linéarité de Landau n'a révélé aucune hiérarchie linéaire de dominance dans les populations de l'étude. Nos résultats soutiennent l'idée que les mâles adultes sont territoriaux, et toute agression manifeste est dirigée presque exclusivement vers les jeunes célibataires qui défient ceux qui détiennent un territoire. [source]

Secondary sexual coloration and CSF 5-HIAA are correlated in vervet monkeys (Cercopithecus aethiops sabaeus)

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2007
M.S. Gerald
Abstract Background, Identifying indirect markers of the physiology or neuroendocrinology of a primate can provide a powerful tool to scientists. Anecdotal descriptions and recent experimental evidence suggests that the colorful sexual skin in adult male vervet monkeys (Cercopithecus aethiops sabaeus) might be sensitive to social changes, including dominance relationships, which could be related to serotonergic activity. The present study examined whether individual differences in scrotal coloration were related to cisternal cerebrospinal fluid concentrations of 5-hydroxyindoleacetic acid (CSF 5-HIAA) in a captive population of vervet monkeys. Results, Darkly colored males had relatively higher CSF 5-HIAA concentrations than paler males, and scrotal color hue was also related CSF 5-HIAA concentrations. Conclusions, These preliminary data are compatible with the hypothesis that scrotal coloration serves as an indirect marker of serotonergic activity. These findings suggest that color assessments might be useful to consider for study design, as well as for animal welfare and captive management. [source]

Dominance relationships among one-male units in a provisioned free-ranging band of the Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains, China

Female dominance in captive gray mouse lemurs (Microcebus murinus)

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2001
Ute Radespiel
Abstract Female dominance or female feeding priority seem to be characteristic for many lemur species, but are rare traits in other primates and mammals in general. The nocturnal lemur species, however, are underrepresented in the quantitative studies on social dominance. The aim of this study is to investigate the pattern of intersexual dominance relationships in the gray mouse lemur (Microcebus murinus), a species that is generally thought to possess a number of ancestral lemur traits. The context, distribution, and outcome of intersexual conflicts are analyzed in four captive groups of gray mouse lemurs. Intersexual conflicts occurred in the study groups in different behavioral contexts and were mostly spatial interactions (chasing/fleeing, approach/avoidance). The majority of conflicts were decided, and were in all but one case won by females. This is the first evidence suggesting unconditional female dominance in a cheirogaleid primate. The existence of female dominance in most families of the Lemuriformes suggests it is an ancient trait that evolved in their common ancestor. Am. J. Primatol. 54:181,192, 2001. © 2001 Wiley-Liss, Inc. [source]

Estimation of dominance genetic variances for reproductive traits and growth traits of calves in Japanese Black cattle

ANIMAL SCIENCE JOURNAL, Issue 4 2004
Takafumi ISHIDA
ABSTRACT The dominance genetic effects for reproductive and calf growth abilities in the practical Japanese Black populations were examined using average information (AI) algorithm restricted maximum likelihood (REML) under animal models. The reproductive traits were observed in Japanese Black cattle maintained at Tottori and Okinawa prefectures, and growth traits of calves were observed in cattle at Okinawa. The average of dominance relationships in Tottori ranged from 0.2 to 0.4%, while the level in Okinawa was lower and sparse compared with Tottori. The proportions of the dominance variances to sum of additive and dominance variances () were all 0.02 for reproductive traits in Tottori. In contrast, the proportion was 0.02,0.64 in Okinawa regardless of the level of dominance relationships. These proportions suggested that the dominance might affect the expression of calving interval, days open and gestation length in Okinawa, where breeding units were spread over many islands. Although the dominance variances could not estimate birthweight, w as 0.34 for calf market weight and 0.27 for average daily gain from birth to calf market in Okinawa. These values also suggested that the dominance might affect the early growth of calves. In the near future, genetic relationships will become more complicated with continuation of the current selection and mating systems. Therefore, genetic evaluation accounting for dominance effects would be necessary for particular traits and populations. [source]