bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pairs and Harems in a Cichlid Fish, Lamprologus brichardi1
Authors: Limberger Dominique 
Published: August 2010

Abstract and SummaryL. brichardi is a substrate brooding cichlid with facultative polygamy. The social organization was studied in the field for a 6‐week period. The mating structure was examined in detail in the laboratory. Two types of social groupings are described:

Aggregations of sexually mature but nonterritorial fish, also frequently visited by territory holders in the vicinity.
Reproductive units (families) mainly consisting of the reproducing pair members and offspring from several broods. All family members defend a common territory around the shelter site. Occasionally a male has access to two females each with a separate territory (harem).

The factors influencing mating structure were investigated in the laboratory:

Females select breeding sites rather than partners.
Without competitors for breeding sites, and with an equal or nearly equal sex ratio, harems were established nearly as often as pairs.
Young males are physically able to mate and form a harem; but they are usually prevented from doing so by more competitive (larger) males.
Competition for breeding sites is not a prime influence on harem formation, although it is of great importance in determining the composition and size of the breeding population.
Just as many pairs as harems were formed with and without predators, even though, with predators, no young survived.
In L. brichardi the formation of harems is not predominantly determined by the distribution of suitable spawning sites. The monopolization of females is only slightly influenced by the distance between their territories.
In L. brichardi it is not necessary for harem formation that the male is bigger than the female.
Behavioural protocols and data on growth rates, as well as spawning intervals, did reveal any consistent difference between pairs and harmes.

Of the variables tested, male competition for females was therefore the sole determinant of who should mate.
Pineal Body and Magnetic Sensitivity: Homing in Pinealectomized Pigeons under Overcast Skies
Authors: Maffei Lamberto , Meschini Enrico , Papi Floriano 
Published: August 2010

Abstract and SummarySince birds use the earth's magnetic field for compass orientation when astronomical cues are lacking and it has recently been suggested that the pineal body is part of their magnetic compass, test releases have been performed in overcast conditions with pigeons deprived of the pineal body. On the whole, both experimental and control birds were capable of homeward orientation, though the bearings of experimental were rather more scattered. No differences in homing speed or success were recorded. Thus, the pineal body does not appear to play an important role in the homing of pigeons.
The Feeding Behaviour of Starlings (Sturnus vulgaris) in the Presence of ‘Eyes’
Authors: Inglis I. R. , Huson L. W. , Marshall M. B. , Neville P. A. 
Published: August 2010

Abstract and SummaryPrevious studies that have looked at the aversive properties of simple, predator‐related, eye‐like patterns presented in an artificial context, have yielded conflicting results. The aim of the present series of experiments was to investigate whether such stimuli had potential for use as bird scarers. The starling (Sturnus vulgaris) was the subject species. The experimental procedure was designed to provide a relevant and objective, interval scale of aversiveness based upon the ability of eye patterns to deter hungry birds from a feeding area.Each subject was deprived of food for 5 h and then tested in an apparatus which exposed an eye pattern over a food trough immediately after the bird alighted on that trough. 10 measures of the starlings' feeding behaviour were monitored over a 1‐h trial. It was predicted that five of these variables would be positively and five negatively correlated with an increase in the fear evoking properties of the stimulus. The 10 measures were analysed using principal component analysis and the first component in every experiment had the signs of the latent vectors of the variables exactly in the predicted pattern and therefore appeared to be an ‘aversiveness index’. The scores from this first component were then used in a Latin square ANOVA to distinguish subject, test order and stimulus effects.The main findings from the eight experiments are as follows. Simple eye‐like patterns can indeed deter hungry starlings from feeding in their vicinity. The presence of a pair of eyes painted on a white card caused an 88% reduction in time spent on the nearby food trough and a 65% reduction in actual feeding time. The presence of ‘pupils’ in the patterns is essential for simple circles alone are not significantly more aversive than the control card. Once a pattern has the ‘pupil/iris’ distinction then a circular outline becomes important although the shape of the ‘pupil’ appears relatively unimportant. Eyes with coloured irises are more effective than black and white patterns but the degree of contrast between the ‘pupil’ and ‘iris’ appears irrelevant. Increasing the number of simultaneously presented eyes from one to three is correlated with an increasing trend in aversiveness which is destroyed if the same stimuli are presented within the context of a simple head outline. Changing the orientation of a pair of eyes from horizontal to vertical only slightly reduces their aversiveness. The size of the patterns appears to be unimportant within the range tested. The aversive properties of eyespots and of broadcast starling distress calls are positively additive. The effectiveness of a stimulus combining all the important features mentioned is as aversive as is a realistic model of the head of an owl.
The Social Structure of Inachus phalangium, a Spider Crab Associated with the Sea Anemone
Authors: Wirtz Peter , Diesel Rudolf 
Published: August 2010

Abstract and SummaryThe behaviour of the spider crab Inachus phalangium (Fabricius, 1775), which lives in association with the sea anemone Anemonia sulcata (Pennant), was studied in the field.The crab was found in the littoral zone of the Mediterranean Sea near Banyuls sur Mer, France, in the whole depth range studied (0.5–25 m). The crabs had a long‐lasting association with individual Anemonia sulcata, occasionally with Aiptasia mutabilis. Most crabs were found in association with the same anemone for several days, some crabs were found in association with the same anemone for longer than one month.In the areas studied, on average 65 Inachus phalangium were found on 100 anemones.Crabs released in the vicinity of anemones moved towards them and entered them. Inachus phalangium could walk between the tentacles of Anemonia sulcata and Aiptasia mutabilis without eliciting feeding reactions of the anemone. The crabs left the anemones for moulting. After moulting masking material was removed from the exuvia and used again. The animals returned into an anemone while still soft. Material used for masking, usually algae, could be picked off the body and eaten. Masking material may be a food reservoir in addition to providing camouflage.Anemones were left only during night‐time. The crabs left their anemone to moult, to feed in the vicinity, fleeing from larger conspecifics, and to migrate to a different anemone.Outside the anemone's protection Inachus was eaten by several species of fish.Individuals appeared to avoid each other. 57% of all animals were found alone on an anemone. Large males and females were more frequently found alone than were small males and females. Fights were observed between members of the same and of the opposite sex. During fights, legs and claws could be torn off.Adult males migrated more often between anemones and moved over larger distances when migrating than did adult females. Adult males probably migrated in search of sexually mature females. Such a roving strategy is evolutionarily stable only when the higher costs (in terms of energy expenditure and mortality) are compensated for by a higher number of offspring than produced in the alternative, pair‐bonding strategy.
A Study of the Behaviour of the Australian Field Cricket Teleogryllus commodus (Walker) (Orthoptera: Gryllidae) in the Field and in Habitat Simulations
Authors: EVANS A. R. 
Published: August 2010

Abstract and SummaryThe behaviour ofT. commodus(Walker) in the field and in simulated natural habitats is described. Regular predictable sequences of behaviour are represented by an ethogram.Most behaviour was centred around burrows or sheltered sites. Burrows appeared to be a limiting resource and there may be behavioural dimorphism in ♂ ♂ (burrower and non‐burrower strategies).Individuals were found to form gregarious clusters and appeared to be attracted to areas already occupied by crickets. Territorial spacing and other social interactions occurred within these clusters.♂ ♂ and ♀ ♀ were found to be mobile, and moved continually between sites. The movement of ♂ ♂ and ♀ ♀ between burrows (calling sites) was measured. Adult ♂ ♂ never remained at a burrow for longer than two days. In simulated natural habitats ♂ ♂ moved in response to two factors: first, and most common, as a result of eviction by other ♂ ♂ second, as a response to the absence of ♀ ♀. When cricket density was increased in habitat simulations crickets clustered at calling sites.The adaptive significance ofT. commodusbehaviour is discussed.
Effects of Prey Movement and Prey Odor on Feeding in Garter Snakes
Authors: BURGHARDT GORDON M. , DENNY DALLAS 
Published: August 2010

Abstract and SummaryThe role of prey movement in feeding behavior was investigated in 10 garter snakes (Thamnophis sirtalis) repeatedly presented with paired stationary and continuously rotating sections of earthworm (Lumbricus terrestris). Additionally, prey odor intensity and source were varied and the performance of a tongueless snake was compared to normal animals.Experiment 1 showed that garter snakes will selectively attack rotating over nonmoving sections of earthworm across a wide range of speeds (1–2048 rpm) with an optimum between 16 and 256 rpm. However, blocking the odor from the sections and presentation of speeds greater than 500 rpm decreased response to moving sections. Experiment 2 showed that at 22–32 rpm moving sections were selected over stationary sections when odor from both was blocked.Experiment 3 assessed the effects of varying ambient odor conditions upon selection of artificial moving and stationary prey. Ambient earthworm odor resulted in a sustained high rate of tongue‐flicking while, with no odor present, snakes showed a gradually increasing rate of tongue‐flicking that declined within a few minutes.Experiments 4 and 5 studied the effects of tongue removal upon the selection of moving and nonmoving prey. Gross changes in the feeding sequence were noted. A long‐term tongue‐less adult fed by opening her mouth and thrashing about her cage when presented with earthworm odor and only preferred moving prey at 32 rpm; a control showed the normal stalk‐and‐strike sequence. The tongueless snake was less attracted to the moving earthworm at a distance than were normal snakes and the use of vision seemed less integrated rather than compensably improved.The results are discussed in reference to the critical flicker‐fusion frequency, klepto‐parasitism, and escape tactics of prey.
Social Stress in the Fieldvole: Differential Causes of Death in Relation to Behaviour and Social Structure
Authors: Rasa O. Anne E. , van den Höövel H. 
Published: August 2010

Abstract and SummaryThe fieldvole (Microtus arvalis) undergoes population density fluctuations associated with mass deaths at high densities. The causes of these mass deaths have not yet been fully explained although hypoglycaemic shock can account for a proportion of them. The study investigates another social stress induced disease, uraemia, and its relationship with social status, sex and behaviour in this species. Behavioural parameters together with blood sugar and blood nitrogen levels were measured in 8 captive groups of 8 animals each over an 8‐day period and the dominance status and sex of animals that died were recorded. In ♀♀ there was a strong negative correlation between attacks received, the frequency of fleeing and blood sugar levels. In ♂♂, attacks received and flight were correlated with elevated blood nitrogen and decreased weight despite increased feeding. Females died showing symptoms typical of hypoglycaemic shock while, in ♂♂, the symptoms were typical for uraemia. The differential causes of death are probably related to the sex‐based differences found in social behaviour and social structure.ZusammenfassungDie Todesursachen von Feldmäusen unter hoher Populationsdichte sind noch nicht völlig erklärt. Bei einigen kann hypoglykämischer Schock die Todesursache sein, aber nicht bei alien. Hier wird untersucht, ob auch Urämie, eine andere durch sozialen Streß ausgelöste Krankheit, eine Rolle spielen könnte.An Gruppen von 8 Feldmäusen, je 3 ♂♂ und 5 ♀♀, in einem großen Käfig unter halbnatürlichen Bedingungen gehalten, wurde das Verhalten beobachtet und Gewicht, Blutzucker und Blutharnstoffgehalt über 8 Tage hinweg gemessen. Die Gruppen stabilisierten sich innerhalb von 24 h; das größte ♂ und alle ♀♀ taten sich zusammen und schlossen die beiden kleineren ♂ ♂ aus. Mehr als 50% der kleinen ♂ ♂ starben, ebenso 25% der kleinen ♀♀. Die ♀♀ starben innerhalb von 4 Tagen, die ♂ ♂ zwischen dem 4. und 8. Tag. Erduldete Angriffe und Flucht korrelierten hoch negativ mit dem Blutzuckerspiegel der ♀♀. Bei den ♂ ♂ korrelierten erduldete Angriffe und Flucht mit einem erhöhten Harnstoff‐ und Zuckergehalt des Blutes und mit — trotz erhöhtem Fressen —abnehmendem Gewicht.Die ♀♀ starben mit Symptomen, die typisch sind für einen hypoglykämi‐schen Schock; die ♂ ♂ zeigten typische Symptome einer Urämie. Beobachtungen des Sozialverhaltens zeigten, daß kleine ♀♀ während der ersten 4 Tage kurz‐zeitigem Streß durch häufige Attacken der großen ♀♀ ausgesetzt waren und dann von den Gruppen aufgenommen wurden. Untergeordnete ♂ ♂ wurden in gleichbleibend hohem Maße von dem dominierenden ♂ angegriffen und niemals in die Gruppe aufgenommen — ein Langzeitstreß‐Syndrom. Die unter‐schiedlichen Todesursachen der kleinen ♂ ♂ und ♀♀ sind wahrscheinlich auf geschlechtsspezifische Unterschiede im Sozialverhalten und in der Sozialstruktur zurückzuführen.
Vigilance Behaviour and Alarm Calls in a Captive Group of Meerkats, Suricata suricatta
Authors: Moran Greg 
Published: August 2010

Abstract and SummaryAt least one member of captive groups of meerkats (Suricata suricatta) typically is situated in a prominent, elevated location. This study provides an initial description of this pattern of behaviour and evidence to suggest that it serves a vigilance function. While on the ledges, animals behaved in an alert and watchful fashion and emitted two particular classes of vocalization in response to potential dangers to the colony. Other group members responded to these alarm vocalizations with a range of alerting and retreating patterns. The vigilance behaviour system provides a useful model for the investigation of several sociobiological hypotheses and of a sophisticated alarm vocalization network.ZusammenfassungIn jeder gefangen gehaltenen Gruppe von Erdmännchen (Suricata suricatta) gab es mindestens ein Tier, das sich gewöhnlich auf eine erhöhte Stelle mit guter Aussicht setzte.In jeweils halbstündigen Beobachtungen, die in drei Serien von je 20mal über 3 Jahre verteilt waren, saß im Mittel in über 95 % der Zeit mindestens ein Tier auf solchem Posten. Ausnahmen betrafen Zeiten nach dem Tod eines Koloniemitglieds.Alle Tiere saßen häufig auf solchen Posten, aber in den letzten beiden Beobachtungsperioden vor allem das erwachsene Männchen. Es verharrte in den beiden letzten Jahren auch jeweils für längere Zeit auf diesem Posten als die anderen Tiere.Die auf dem Aussichtsposten befindlichen Tiere verbrachten mehr Zeit aufgerichtet und die Umgebung musternd als die Tiere, die sich anderswo aufhielten.Die meisten Alarmrufe kamen von Tieren auf dem Aussichtsposten. Sowohl die Alarmrufe der Individuen wie die Reaktionen der anderen darauf sind verschieden. Auf Tonbandrufe reagieren die Tiere zunächst mit Deckungsuche, doch verliert sich die Reaktion mit häufigerer Wiederholung.Das Sitzen an erhöhter Stelle scheint ein wichtiger Bestandteil der Sozialstruktur zu sein und als Wächter‐Amt zu dienen. Wachesitzen ist unverträglich mit Fressen und anderem Selbsterhaltungs‐Verhalten. Das Wächter‐Amt der Surikaten weist auf einen hohen Verwandtschaftsgrad innerhalb der Gruppen hin.
The Effect of Early Experience on the Development of “Aggressive” Behaviour in Formica lugubris Zett. (Hymenoptera: Formicidae)1
Authors: Moli Francesco Le , Mori Alessandra 
Published: August 2010

Abstract and SummaryThe possible rôle of early experience in the development of aggression in Formica lugubris Zett. was examined by setting up artificial colonies containing young workers hatched on the same day. Group 1 consisted of young workers hatched in the presence of homospecific adults, and so having “normal” experience. Group 2 young workers were reared from hatching with Formica rufa L. adults, and so had “altered” experience. Group 3 had young workers drawn from cocoons and reared in isolation from adults. Intra‐ and interspecific aggressive behaviour of the young workers in the three categories were analysed and quantified 16 and 30 days after hatching, after staging fights with F. lugubris and F. rufa.In group 1 no conspecific aggression was evident, but attacks were almost always recorded in heterospecific encounters. In group 2 there was no tolerance of homospecifics, initial contact frequently being followed by immediate over attack with all elements of aggressive behaviour. The reverse applied for F. lugubris with “altered” learning and F. rufa workers, there was mutual recognition and acceptance, as they were ants of the same colony. The young workers reared in isolation (group 3) fought in 60 % of homospecific encounters on the 16th and 40% on the 30th day; disturbance of conspecific recognition was clear. Nevertheless combat occurred in almost all heterospecific encounters.This work demonstrates that differences in early experience may influence the amount and direction of aggression in F. lugubris ant‐workers at 16 and 30 days of age. This may explain the existence of slave‐workers in natural dulotic societies.ZusammenfassungDer Einfluß früher Erfahrungen auf die Entwicklung der Aggression bei der Ameise Formica lugubris wurde in künstlichen Kolonien an Arbeiterinnen geprüft, die am jeweiligen Tag geschlüpft waren, und zwar in Gruppe 1 unter Artgenossen, in Gruppe 2 unter Erwachsenen von Formica rufa; Arbeiterinnen der Gruppe 3 waren aus Kokons geholt und handaufgezogen. Inner‐ und zwischenartliches Angriffsverhalten wurden am 16. und 30. Tag nach dem Schlupf analysiert. In Gruppe 1 gab es keine deutliche Aggression zwischen Artgenossen, wohl aber beim Zusammentreffen mit F. rufa. — In Gruppe 2 gab es bei den ersten Kontakten mit Artgenossen häufig sofort Angriffe und alle Elemente aggressiven Verhaltens; hingegen waren die aus derselben Kolonie stammenden F. lugubris und F. rufa friedlich miteinander. — Isoliert aufgezogene Arbeiterinnen kämpften am 16. Tag in 60%, am 30. Tag in 40% der Begegnungen mit Artgenossen, aber auch in fast allen Begegnungen mit Artfremden.Frühe Erfahrung hat also einen Einfluß auf das spätere Aggressions‐verhalten. Das dürfte bei Sklavenhalter‐Ameisen eine Rolle spielen.
The Breeding System of the Acorn Woodpecker in Central Coastal California
Authors: Koenig Walter D. , Mumme Ronald L. , Pitelka Frank A. 
Published: August 2010

Abstract and SummaryThe breeding system of the acorn woodpecker in California is detailed, and evidence supporting the occurrence of both cooperative polygamy (polygynandry) and nonbreeding by group offspring still living in their natal territory (helping) is presented. Both these phenomena occur independently and often simultaneously within the population. Although groups almost invariably consist of close relatives, incest is avoided, apparently by the recognition of close relatives. However, 10 cases of known or probable inbreeding have been recorded, resulting both from philopatry and from breakdowns in the usual pattern of incest avoidance. The latter appears to occur when the cost of attracting an unrelated mate is unusually high; the overall extent and significance of inbreeding in the acorn woodpecker remain to be determined.ZusammenfassungEichelspechte leben in Gruppen, die aus einem “Brüterzentrum” (bis zu 4 Männchen und 2 Weibchen) bestehen und den nichtbrütenden Helfern; das sind bis zu 10 Nachkommen beiderlei Geschlechts aus mehreren Vorjahresbruten der Gruppe. Brutgruppen entstehen, indem sich eine Gruppe von Schwestern und eine Gruppe ihnen verwandtschaftlich nicht nahestehender Brüder zusammenschließen. Hinzu kommen dann Zuwanderer und die eigenen Nachkommen. Diese brüten in der Familie nicht, es sei denn ein andersgeschlechtiger Elter stirbt und wird durch einen Fremden ersetzt. In diesem Falle können Nachkommen brüten, obwohl ihr gleichgeschlechtiger Elter noch in der Gruppe ist. Sterben alle Brüter eines Geschlechts, wandern andere Individuen dieses Geschlechts ein; Zuwanderer gibt es aber auch zusätzlich.Zuwanderer sind 1. Geschwister von Brütern, 2. Gruppennachkommen, die nach einem erfolglosen Brutversuch außerhalb wieder daheim Heifer werden, 3. Gruppennachkommen, die kein Auswandererglück hatten und im heimatlichen Revier brüten, nachdem ihr andersgeschlechtiger Elter starb. Als Folge dieser Brüt‐Ordnung wird Inzest weitgehend vermieden, offenbar zum Teil durch Verwandtschaftserkennen. Dennoch sind 10 Fälle von Inzucht beschrieben; 5 davon nach einem Zusammenbruch des Verwandtschaftserkennens, 5 aus Ortstreue. Inzucht scheint aufzutreten, wenn die Kosten für das Anwerben eines unverwandten Partners ungewöhnlich hoch sind. Wie häufig das vorkommt und welche Folgen es für das Sozialverhalten hat, bleibt zu untersuchen.