Shopping cartBehaviour
Volumes & issues:
-
System Interaction of Dummy-Elicited Behavior in the Jewel Cichlid, Hemichromis Bimaculatus Gill
- + Show Description - Hide Description
-
The responses of male Hemichromis bimaculatus toward stationary dummies presented for time intervals of 15-60 minutes were studied. The following results were obtained: I) The fish responded to the dummies with many of the same activities shown during encounters with live conspecifics. 2) At low frequency or duration activities directed toward the dummy were often diverse but at relatively high levels certain activities dominated behavior during dummy presentation. The latter led to categorization of behavior into response types, biting-, quivering-, fluttering-, and finrest-dominated, which are negatively correlated with each other at high levels. 3) A male which previously responded to a dummy with a quivering-dominated response while unpaired switched to a biting-dominated response to the dummy when paired with a live female. 4) Certain activities, namely lateral display and tailbeating, occurred during both biting-dominated and quivering-dominated responses but gradually decreased during the course of an observation period. It was concluded that each response type reflects a dominance of corresponding tendencies or systems in the fish's behavior and that certain activities associated with these systems are mutually inhibitory. Furthermore, there is evidence suggesting that two of these systems (fluttering and finrest) comprise behavior that is usually regarded as a single system. Lateral display, tailbeating and quivering are considered in terms of interaction between systems.
-
Les Relations Sociales Chez Le Cobaye Domestique MaleI. Etude De La Hierarchie Sociale
- + Show Description - Hide Description
-
I. La hiérarchie sociale établie entre les mâles de plusieurs groupes de Cobayes domestiques a été étudiée. Un indice hiérarchique basé sur le rapport du nombre des agressions exercées et subies par un même animal permet de déterminer avec précision le rang de chaque individu. 2. La hiérarchie observée est strictement linéaire et sa stabilité est bonne. Toutefois les périodes d'activité sexuelle correspondant à l'oestrus des femelles peuvent être à l'origine de renversements hiérarchiques entre mâles proches. 3. quantitative précise montre un maximum d'agressivité chez les mâles a et , ce dernier étant aussi le plus agressé. Les mâles les plus inférieurs sont peu agressifs et moins agressés que l'on pouvait le supposer. La hiérarchie tend à s'estomper à leur niveau. De plus, chaque mâle agresse de manière privilégiée son subordonné immédiat. Les postures ambivalentes sont observées seulement entre a et entre lesquels la compétition s'établit à son maximum. 4. Les séquences de comportements montrent une ritualisation importante des postures utilisées mais varient selon les couples de mâles qui s'opposent. Ceci permet de penser que les mâles d'un groupe ont une certaine connaissance de la situation hiérarchique de chacun d'eux. 5. Cette modulation des patterns comportementaux apporte confirmation du rôle de la situation dans les séquences de communication et de l'adaptation des réponses en fonction de l'expérience passée et de l'environnement immédiat.
-
Les Relations Sociales Chez Le Cobaye Domestique Male
- + Show Description - Hide Description
-
Nous avons étudié les réactions comportementales de Cobayes mâles dominants placés en présence d'un étranger, sur le territoire de ce dernier ou sur leurs propres territoires. 1. Il est possible de décomposer les affrontements en trois phases: - Une phase d'approche et de prise de contact. - Une phase d'affrontement pendant laquelle les animaux vont établir des relations de dominance. - Une phase finale où les relations préétablies se confirment, chaque animal subissant en quelque sorte son propre statut. 2. L'analyse de la deuxième phase permet d'obtenir de longues séquences comportementales. Il apparaît que le dominant présente dix fois plus de SAS offensifs que défensifs alors que le dominé possède une balance comportementale équilibrée. 3. Le comportement d'un animal apparaît déterminé de manière statistique par: - Le comportement de l'adversaire, - Le comportement antérieur de l'individu lui même. Premièrement, les actions offensives entraînent préférentiellement une réponse défensive, chez les deux animaux, les actions défensives du dominé entraînent les réponses offensives du dominant. Néanmoins, les postures ambivalentes offensives provoquent généralement des réponses offensives de même type. Deuxièmement, en plus de ce déterminisme externe, une tendance générale à l'escalade aggressive se manifeste chez les deux opposants, ainsi qu'une tendance à l'escalade défensive chez le dominé seulement. Il se confirme ainsi que l'affrontement est l'expression d'un conflit agression-fuite dont le point d'équilibre est constitué chez le Cobaye par la Posture Offensive Oblique. 4. La comparaison entre la hiérarchie de groupe et les affrontements permet de penser que ceux-ci sont un moyen de résolution du conflit et d'établir des relations de dominance par sélection des réponses adaptées à la situation c'est-à-dire en définitive aux réactions de l'adversaire. L'ontogénèse sociale et l'affrontement parviendraient ainsi au même résultat par des moyens fort différents. Le comportement, loin d'être stéréotypé, serait alors l'expression d'une situation instantanée (séquences interindividuelles) et de la mémoire de l'animal (expériences préalables, comportements antérieurs). Cette dernière serait susceptible au niveau du système nerveux de provoquer une modification adaptative des réponses observées. 5. Enfin, la nature des deux combattants apparaît prédominante sur le lieu de la rencontre, ce qui laisse supposer l'existence d'une variabilité agressive individuelle dont l'origine est encore imprécisée.
-
The Organization of Dustbathing Components in Bobwhite Quail (Colinus Virginianus)
- + Show Description - Hide Description
-
The components of dustbathing in 12 male and 12 female Bobwhite quail (Colinus virginianus) were described. These components form a sequence of entering the dust, pecking and scratching in the dust while standing, squatting in the dust, pecking and scratching in the dust while squatting, movements of the wings and feet to toss dust onto the ruffed plumage (dust toss), rubbing the head and side in the dust (head rub and side rub), rising, ruffling the feathers and vigorously shaking the dust out of the plumage (ruffle-shake), exiting the dust, and engaging in other behavior such as eating and drinking. Two tests were conducted at 1 day of deprivation of dust (to assess the reliability of both frequencies and sequences of components) and one test at 5 days of deprivation (to assess changes in these measures with increases in deprivation). The frequencies of seven of these components and the sequence in which the components first occurred had statistically significant reliability coefficients at both levels of deprivation. The frequencies of the components involved in driving dust into the plumage (dust toss, head rub, side rub) were significantly correlated. A statistic to measure the stability of these correlations was introduced. The frequencies of eight of the components showed significant increases with greater deprivation of dust. Male birds showed more of an increase with deprivation in the frequencies of the head and side rub components than did female birds. The sequence in which the components occurred was analyzed. The first occurrences of the dust toss, head rub, and side rub components were invariably in this order, for all of the birds tested at each deprivation level. The order of the first occurrences of the remaining components was variable. Individual components were generally repeated many times throughout a sequence; the order of each occurrence of each of the components was extremely variable between birds and tests. These results are discussed in terms of a lipid regulation model which suggests that dustbathing serves to remove lipid substances from the plumage.
-
A Description and Analysis of Agonistic Behavior Patterns in an Opisthobranch Mollusc, Hermissenda Crassicornis
- + Show Description - Hide Description
-
Observation of the encounters which occurred among pairs of Hermissenda crassicornis demonstrated the following: 1. Twenty percent of the encounters are agonistic, involving lunging or biting or both. 2. Agonistic behavior more often follows when the animals meet anterior-to-anterior than when they meet in any other configuration. 3. Initiators of encounters are more likely to win than non-initiators. They are larger than non-initiators and enter encounters head-first more frequently. Knowledge of either the position of the animals or the initiator allows relatively accurate predictions of the eventual winner. Additional knowledge of the size difference does not contribute to improved predictability. 4. The behavior patterns were recorded using I.5 second sampling periods. The sequence of behavior patterns is consistent with a first order Markovian model; this is primarily due to the strong tendency to repeat a pattern just displayed. One can predict the following behavior pattern with an accuracy of 1/3 to 1/4. 5. After removal of the repeated behavior patterns, the transitions between patterns are still consistent with a first order Markovian model. One can now predict the following behavior pattern with an accuracy of 1/5 to 1/6. There exists a greater possibility than before that higher orders of dependency might contribute to the sequence of behavior patterns. 6. The sequence of behavior patterns of agonistic encounters are more rigidly organized than the sequence of non-agonistic encounters. 7. It appears that winners and losers of encounters react in a similar manner to a given behavior pattern of the other.
-
A Comparative Study of Facial Expressions of Two Species of Pinnipeds
- + Show Description - Hide Description
-
Fur seals Arctocephalus forsteri and walruses Odobenus rosmarus show similar facial expressions in a variety of social and non-social contexts. In non-social settings, both species modify the facial appearance by erecting the mystacial vibrissae while grooming the forequarters, while yawning, and during olfactory/tactile investigation of objects. During naso-nasal greetings, vibrissae are often erected in fur seals, and are erected and moved against the interactant's mystacial pads in walruses. Highly submissive animals show: for A. forsteri, erection of the vibrissae, wide gape, relaxed lips, posterior retraction of the corners of the mouth, wide-eyed stare; for walruses, dorsomedial drawing up of the mystacial pads and erection of the vibrissae, imparting a 'pig snout' appearance. In high intensity threat, both species show facial expressions involving: for A. forsteri, slight lateral expansion of the mystacial pads, slight to moderate opening of the mouth, direct or oblique visual orientation from a head-up posture; for O. rosinarus, lateral and dorsoventral expansion of the mystacial pads, attendant exposure and stretching of the skin of the upper lip, especially around the bases of the tusks, and inflation of the rostrum posterolateral to the nostrils. The similarities of form and context of facial expressions used by the two species suggest common causation, but a greater number of those of A. forsteri is considered communicative, in agreement with known ecological and social characteristics of the two species.
-
Some Special Features of the Leaf-Rolling Technique of Byctiscus Populi L. (Coleoptera, Rhynchitini)
- + Show Description - Hide Description
-
Females of the weevil Byctiscus populi construct rolls from young poplar leaves. Within these rolls the eggs are deposited and the larvae develop by feeding upon the innermost leaf-coils. By boring a hole in a petiole or young twig, one or more leaves will fade, and are ready to be wrapped up. About 95% of the rolls constructed are preceded by the boring of a hole in a petiole (P-rolls) ; these rolls each consist of a single leaf. For the construction of the other rolls (5%), a hole is bored in a young twig; these rolls may contain a single (T-rolls) or a few leaves (TT-rolls). Only when one or more of the faded leaves droop within reach of a newly constructed T-roll, may the female wrap up one or more extra leaves into that roll and by so doing a TT-roll arises (in about 29% of the cases in which holes are bored in twigs). The construction of P-, T- and TT-rolls respectively is described and compared. T- and TT-rolls can almost only be made at the beginning of the reproductive season, when the shoots are still soft enough for the females to bore holes in them. In correspondence with the softness of the shoot, are the rolls made from very young soft leaves. Contrary to this, P-rolls can be made during the whole season (from May until the end of August) from slightly less soft young leaves. By eating from a selected leaf, the female is able to discriminate between very young leaves - followed by boring in twigs - and other young leaves - followed by boring in petioles. The size of the food supply for the larvae depends on the size of the wrapped up leaf. The leaves in P-rolls are generally larger than those in T- and TT-rolls, but the nutritional value of the leaves in T- and TT-rolls is greater than that of leaves in P-rolls. Nevertheless, relatively more reproductively fit weevils develop from P-rolls than from T-rolls, whereas TT-rolls resemble P-rolls in this respect. Hence, the more T-rolls are transformed into TT-rolls, the lower the reproductive disadvantage from the construction of T-rolls. In spite of the above reproductive disadvantage and of the fact that the construction of T- and TT-rolls requires more effort and time than that of P-rolls, at the beginning of the reproductive season the females preferably construct T- and TT-rolls. This apparent paradox is explained by the discovery that the boring in twigs in May results in the development of secondary shoots in July and August, by which the sharply diminished supply of leaves suitable to be wrapped up is highly increased again. The reproductive season is essentially prolonged by the development of these secondary shoots. Therefore, each of the three kinds of rolls has its own value for the survival of the species.
back to top