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1.
Hiroshi Ihobe 《Primates; journal of primatology》1989,30(1):17-25
When the individual Japanese macaques of the Koshima troop feed on natural food, they usually feed alone. In situations where
animals usually feed without other animals, there is a possibility that subordinate animals may avoid feeding sites at which
dominant animals are feeding. This paper examines whether social relationships such as kinship or dominance exert any influence
on an animal's choice of feeding sites, by analyzing episodes in which an animal approached and climbed into a tree where
other animals were. As a result, it was found that social relationships did not influence whether an animal climbed into a
tree where other animals were feeding, and that no particular age-sex pair co-fed. Agonistic interactions frequently occurred
when the inter-individual distance was less than 1 m. From these findings, the feeding sites were divided into two spaces:
(1) a tolerance feeding space, and (2) an intolerance feeding space. It is presumed that animals can feed without entering
others' intolerance feeding spaces when food is abundant, as it was in the present study period. Thus social relationships
do not influence an animal's choice of feeding sites in such a situation. 相似文献
2.
The changes of dominance rank among female Japanese monkeys of the Koshima group over a period of 29 years from 1957 were
studied. The dominance rank order was relatively stable in the early population growing phase, while large scale-changes of
dominance rank order occurred successively in the phase of population decrease brought about by the severe control of artificial
feeding after 1972. Nevertheless, the rank order of several females of the highest status was stable. Furthermore, the reproductive
success of these highest status females was high (Mori, 1979a;Watanabe et al., in prep.). Divergence of the dominance rank order fromKawamura's rules (Kawamura, 1958) was observed in the following respects: (1) Some females significantly elevated their rank depending on the leader
males. (2) If mothers died when their daughters were still juveniles or nulliparous, the dominance rank of some of these offspring
females was significantly lower than the mother's one. However 55% of daughters which lost their mothers at a young age inherited
the mother's rank. (3) Dominance among sisters whose mother had died when at least one of the daughters was under 6 years
old followed the rule of youngest ascendancy in 60% (Kawamura, 1958), and in 80% when both of the daughters were nulliparous at the mother's death.
The mean rate of aggressive interactions for each female with subordinates to her was calculated by dividing the total aggressive
interactions between the female in question and her subordinates by the number of subordinate females to the female in question.
A female which showed a high rate of aggressive interactions with her subordinates was categorized as an “Attacker”, and a
female showing a lower rate was categorized as a “Non-attacker”. Similarly, categories of “Attacked”, and “Non-attacked” were
distinguished by using the rate of aggressive interactions with dominant females. Several females which were once categorized
in one category in a year were repeatedly categorized in the same category over different years. The “Attacked” tended to
be females of higher rank, and “Non-attackers” tended to be females of lower rank. “The second-higher-status females”, were
“Attacked”, and their rank was unstable. In particular, females of lower rank within the lineage of the highest rank suffered
this kind of severe status. Most of the daughters of these females showed a sharp drop of rank, and died when they were still
at a young age, i.e. “the second-higher-status females” displayed low fitness. “Non-attackers” were significantly “Non-attacked”;
i.e. they were females which showed a non-social attitude. Females which underwent a drop of rank tended to be “Non-attackers”.
The most important factor which determined the females' rank was the memory of their dominance relations under the influence
of their mother [dependent rank (Kawai, 1958)] in their early life during development. This finding corresponds well with the results in baboons obtained byWalter (1980); the target females of aggressive interactions by adolescent females were determined by the rank of the mothers when
these adolescent females were born. 相似文献
3.
Dominance among male chimpanzees in the Mahale Mountains National Park,Tanzania: A preliminary study
Hitoshige Hayaki Michael A. Huffman Toshisada Nishida 《Primates; journal of primatology》1989,30(2):187-197
Dominance relationships among male chimpanzees in the Mahale Mountains National Park, Tanzania, were analyzed. Although all
adolescent males were unequivocally subordinate to all adult males, dominance relationships within the age classes were much
less clear. Especially among adolescent males, few pant-grunts or agonistic interactions occurred. While adolescent males
frequently pant-grunted at adult males, these latter males, except the alpha and the youngest, rarely pant-grunted to one
another. This suggests that a difference of social status exists between adolescent and adult males. Adult males rarely display
overt dominance to one another probably because the presence of other males affects their interactions. Moreover, they seem
to try to keep their dominance relationship ambiguous when making it overt is not advantageous to them. This may be a political
way for males to coexist with one another in a unit-group. 相似文献
4.
The regeneration of canopy and subeanopy species in a mid-elevation, primary rain forest in the Coastal Range of Isla de Chiloé (42°30S), in the cold-temperate region of Chile, was studied by comparing seedling and sapling abundances under the forest canopy, and within 36 tree-fall gaps. The forest was dominated byAmomyrtus luma andLaurelia philippiana (33 and 32% of the main canopy individuals), and two subcanopy species (Myrceugenia ovata, andMyrceugenia planipes) were also important. Uncommon species in the canopy wereDrimys winteri, Amomyrtus meli, andRaphithamnus spinosus. Tree-fall gaps were created generally by the fall of several trees, and the main canopy species were the principal gap-makers. Gap sizes varied between 28 and 972 m2, with a mean of 197 m2. Seedling and sapling abundances indicate that the dominant species are capable of regenerating below the canopy, but they also germinate and show enhanced growth within small light gaps. For one of the common subcanopy species (M. planipes) and the two infrequent canopy species (D. winteri, andA. meli) regeneration seems to depend entirely on tree-fall gaps. Thus, in this forest, light gaps allow the persistence of infrequent canopy species, but seem less important for the regeneration and maintenance of dominant canopy species. 相似文献
5.
Changes in brain serotonergic activity during hierarchic behavior in Arctic charr (Salvelinus alpinus L.) are socially induced 总被引:1,自引:0,他引:1
Svante Winberg Göran E. Nilsson K. Håkan Olsén 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1992,170(1):93-99
Summary The experiment was performed in two phases. During the first phase (phase 1) the dominance hierarchy was determined in 4 groups of Arctic charr (Salvelinus alpinus L.), each group consisting of 4 fish. Phase 2 was started by rearranging phase 1 fish into 4 new groups. Group 1 consisted of previously dominant fish and groups 2, 3 and 4 of fish that previously held rank 2, 3 and 4, respectively. After phase 2 telencephalon and brain stem were analyzed with regard to their contents of serotonin (5-hydroxytryptamine, 5-HT) and 5-hydroxyindoleacetic acid (5-HIAA), the principle metabolite of 5-HT. No correlation was found between the social rank (measured as dominance index) during phase 1 and the brain serotonergic activity (measured as the ratio 5-HIAA/5-HT) determined after phase 2. However, most important, the 5-HIAA/5-HT ratio was significantly correlated with the last experienced social rank, i.e. that acquired during phase 2. These results shows that the difference in brain serotonergic activity between dominant and subordinate fish develops through social interactions. Further, we found that previous subordinate experience inhibited aggressive behavior, an effect which, in the light of available information on stress and 5-HT, could be related to the increase in brain serotonergic activity. We hypothesize that stress induces an increased serotonergic activity which in turn inhibits the neuronal circuitry which mediates aggressive behavior.Abbreviations
5-HT
serotonin (5-hydroxytryptamine)
-
5-HIAA
5-hydroxyindoleacetic acid 相似文献
6.
Osamu Katano 《Environmental Biology of Fishes》1992,35(4):343-350
Synopsis Paired males of the dark chub, Zacco temmincki, buried released eggs by vibrating their anal fin, but this behavior was prevented and eggs were cannibalized when many satellites (males and females) were present. A number of satellite males also caused a loss to paired males in sperm competition on spawning grounds far from shelters. Paired males followed repeating tactics, which were defined as successive spawning acts at the same redd, in most cases, but occasionally did shifting tactics which refer to spawning acts conducted successively at different redds. The proportion of the shifting tactic was not correlated with the dominance status of paired males. The shifting tactic was not advantageous in performing spawnings frequently. The calculation of the total advantage of both tactics indicated that the shifting tactic itself was not more beneficial than the repeating tactic at any density of satellites. Since a number of satellites stayed around the redd when no spawning pair was present, or pursued a pair or a single dominant male moving between spawning grounds, the occasional shifting tactics of paired males functioned to confuse and disperse satellites. The spawning tactics of paired males apparently reflected potential fitness costs of satellites. Paired males mainly spawned at the redds near shelters, despite the fact that more satellites were present to devour eggs, presumably because they could obtain many females and monopolize fertilizations. 相似文献
7.
L. P. Jones W. A. Compton 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,70(3):318-321
Summary The use of several S1 individuals to represent an S0 individual permits the use of a Design II mating scheme for plants with only one pistillate flower per plant. Estimates of additive (V
A
) and dominance (V
D
) variance from this mating scheme will be biased upwards, when a small number (10) of individuals of each S1 line are used. This bias can be computed, and the additive and dominance estimates can be corrected. Of particular interest is the observation that the additive genetic variance contributes to bias in estimates of V
D
. When S0 plants are non inbred and their selfedprogeny (S1 lines) are used to represent them in developing families for use in the Design II,
where m1 is the number of individuals used to represent an S1 line in developing half sib-families and m2 is the number of individuals used to represent the S1 line in making up full sib-families. For example, in a 3×3 Design II, with about 10 individuals used to represent each S1 line in each cross, m2 = 10 and m1 = 30. When m1 = m2 = 1,
and
Joint contribution from Department of Agronomy, University of Nebraska 68583, and the S. S. Cameron Laboratory, Werribee, Victoria 3030, Australia. Published as paper No. 7395, Journal Series 相似文献
8.
Angela Meder 《Primates; journal of primatology》1990,31(1):51-63
Studies of the behaviour of 26 (12 males and 14 females) captive infant and juvenile lowland gorillas showed clear sex differences.
Females showed greater interest in young infants and were more active in nest building as well as in solitary and social grooming.
Males were more active in locomotive, dominance, and aggressive behaviour and in social play. Hand-rearing further increased
aggression. Males were more aggressive when they lived with only one partner, and they rose in rank even above older females,
a pattern that has not been observed in naturally reared gorillas. 相似文献
9.
Dario Maestripieri 《Primates; journal of primatology》1994,35(4):443-453
Data from over 400 hr of observation of mother-infant rhesus macaques indicate that during the first 12 weeks of lactation
infants are at risk from other group members and that mothers use aggression as well as restraining to protect them. Maternal
aggression was negatively correlated with infant restraining. High-ranking mothers reacted aggressively to individuals handling
their infants more than did middle- and low-ranking mothers. Conversely, middle- and low-ranking mothers restrained their
infants more than did high-ranking mothers. Maternal aggression did not vary with infant age. Maternal aggression was directed
toward a higher proportion of higher-ranking adult females and their immature offspring and was more likely to be followed
by counter-aggression than nonmaternal aggression, i.e. aggression not related to interactions involving the infant. Middle-and
low-ranking mothers suffered higher costs in terms of retaliation than high-ranking mothers. It is argued that the occurrence
and distribution of maternal aggression among species and individuals should depend on the risk posed to infants by conspecifics
as well as on the characteristics of the social structure (e.g. degree of asymmetry of agonistic contests) and of the mother
(e.g. her dominance rank) which may affect the probability of retaliation. 相似文献
10.