bluuebunny/crossref_metadata_2025 huggingface dataset:
Sexual Interference and Sexual Defense in the Smooth Newt, Triturus vulgaris (Amphibia, Urodela, Salamandridae)
Authors: Verrell Paul A.
Published: August 2010

Abstract and Summary

When a male smooth newt encounters a ♀ who is already engaged in courtship, he may mimic her behaviour during the spermatophore deposition and transfer stages of the courtship. He thereby usurps the courting ♂ and may inseminate the ♀ himself. Such sexual interference depresses the short‐term, and perhaps long‐term, mating success of the courting ♂.

In the presence of a potential rival, the courting ♂ alters certain aspects of his sexual behaviour. He displays more intensely to the ♀ and attempts to draw her away from the rival by increasing the duration of his display. He may also “check” that it is the ♀, and not the rival, who will elicit the deposition of a spermatophore from him. These changes in the behaviour of the courting ♂ are interpreted as defense against sexual interference.

Female smooth newts may be multiply inseminated as a consequence of sexual interference; this may result in sperm competition. However, ♀♀ seem to find competitive interactions between ♂ ♂ “aversive”.

Sexual interference by ♀‐mimicry and associated defensive behaviour patterns are common in the urodele amphibians. Interference can be thought of as a “side‐payment” conditional mating strategy.
Wie richtet eine Flußseeschwalbenkolonie (Sterna hirundo) ihr Abwehrverhalten auf den Feinddruck durch Silbermöwen (Larus argentatus) ein?
Authors: Becker Peter H.
Published: August 2010

Abstract and Summary

How a Common Tern (Sterna hirundo) Colony Defends itself against Herring Gulls (Larus argentatus)

The subject of this study is the anti‐predator behaviour of a small common tern colony near a large herring gull colony on the island of Mellum, West Germany (Fig. 1). In 1980 the number of gulls crossing this tern colony increased during the terns' chick‐stage (Fig. 4). Observed predation of tern chicks was independent of tide and time of day (3., Fig. 5). The frequency of tern reactions corresponded to the number of herring gull crossings (Fig. 5, Table 1). The terns' responses increased between morning and evening (Fig. 8).

Tern up‐flights and attacks increased absolutely and as a percentage, with the advance of the breeding season (Fig. 3, 4). They were positively correlated with the observed chick predation and the number of pairs with chicks, most markedly with chicks older than 5 days (Figs. 3, 4; Table 1). This increased defence was maintained by fewer pairs as, by then, many had lost their own broods (Fig. 4). As the breeding season progressed, herring gulls increasingly became the main cause of tern up‐flights and the object of the attacks (Figs. 9–11). The up‐flights of the whole colony, which occurred frequently and spontaneously during incubation, were observed only rarely after hatching and were almost exclusively a response to herring gulls (Figs. 10, 12).

The lower herring gulls flew over the colony, the more frequently common terns flew up or attacked and the more individuals were involved in these responses (Figs. 6, 13, 14). During the breeding period, communal up‐flights and attacks by terns increased as a percentage (Figs. 12, 13, 15–17). Group‐attacks effected changes in the gulls' flying‐routes more often than did individual attacks (Fig. 18).

Despite the defence behaviour and its adaptation to the predation pressure, herring gulls often succeeded in robbing chicks. This is why the breeding success of the common tern was poor (< 0.4 chicks/nest). Possible reasons for this are discussed.
Large Scale Changes over 19 Years in Songs of Humpback Whales in Bermuda
Authors: Payne Katharine , Payne Roger
Published: August 2010

Abstract and Summary

163 songs of humpback whales (Megaptera novaeangliae) recorded near Bermuda during April and May of 13 years between 1957 and 1975 have been analysed as continuous sound spectrograms and compared. In each year's sample, all whales were singing basically the same song. However, the song was changing conspicuously and progressively with time so that songs separated by a number of years were very different in content. All the songs showed basic structural similarities so that it is possible to define a song form which characterizes songs from many years. We present some basic characteristics of the song form and consider the nature and extent of changes in content as a function of time. An analysis of the songs sung by groups of whales shows that normal singing continues even when whales are close enough, presumably, to hear each other. Such analysis demonstrates inter– and intra– individual variability, none of which is as great as the variation between songs of consecutive years. We do not understand the significance of changing songs. We know of no other non‐human animal for which such dramatic non‐reversing changes appear in the display pattern of an entire population as part of their normal behavior.

In 13 Jahren (1957–1975) wurden bei Bermuda, jeweils von April bis Mai, 163 Gesänge von Buckelwalen aufgenommen und analysiert. In jedem Jahr sangen alle Wale im Grunde denselben Gesang. Über die Jahre änderten sich diese Gesänge deutlich; Gesänge, zwischen denen mehrere Jahre lagen, waren deutlich verschieden.

Alle Gesänge haben den gleichen Grundaufbau, an dem sich Änderungen über die Zeit aufzeigen lassen. In Walgruppen treten Gesänge auch dann auf, wenn die Tiere in Hörweite voneinander sind. Intra– und interindividuelle Unterschiede waren kleiner als die Unterschiede zwischen aufeinanderfolgenden Jahren.

Die Bedeutung der Gesangsänderung ist unbekannt. Von keinem anderen Tier ist solche Weiterentwicklung eines Signalverhaltens einer ganzen Population berichtet worden.
The Role of Song and Vocal Imitation among Common Crows (Corvus brachyrhynchos)
Authors: Brown Eleanor D.
Published: August 2010

Abstract and Summary

The song of the common crow (Corvus brachyrhynchos) is examined as an intragroup bonding mechanism. The song repertoires of 3 social groups (4 tame siblings, 2 tame individuals, and one wild family of 6 birds) were studied over a 2½–year period. Data include information on group‐specific differences, changes during ontogeny, and contexts in which song occurs. Differences among song repertoires were correlated with membership in specific social groups; within one captive social group of siblings, sharing of song sounds changed over time and was related to social bonds between particular individuals. Use of song in various contexts indicated that it reduced aggression and facilitated affiliative behaviors among group members. Vocal imitation resulted in convergent repertoires subsequent to the introduction of previously unfamiliar birds. The possible significance of song and vocal imitation is discussed in relation to crow social structure.

Das Gesangsrepertoire der Krähe Corvus brachyrbynchos wurde in drei sozialen Gruppen (4 zahme, handaufgezogene Geschwister; 2 zahme Individuen; eine freilebende, aus 6 Individuen bestehende Familie) über 2½ Jahre hinweg untersucht. Unterschiede im Gesangsrepertoire waren mit der Mitgliedschaft in einer bestimmten Gruppe korreliert: einzelne Elemente wurden von mehreren Individuen gesungen. In der Geschwistergruppe änderten sich die Gemeinsamkeiten im Laufe der Zeit, abhängig von den Sozialbeziehungen zwischen bestimmten Individuen. Aus dem Kontext, in welchem Gesang auftrat, läßt sich schließen, daß Gesang Aggression vermindert und Sozialbeziehungen innerhalb der Gruppe fördert. Wenn bislang fremde Krähen mit unterschiedlichem Gesangsrepertoire zusammengebracht wurden, war die Integration in die Gruppe zeitlich mit der Nachahmung von Gesangselementen korreliert und resultierte in einem gemeinsamen Gesangsrepertoire. Die mutmaßliche Bedeutung von Gesang und Gesangsnachahmung für die Sozialstruktur der Krähen wird besprochen.
Ichneumia alhicauda and the Evolution of Viverrid Gregariousness
Authors: Waser Peter M. , Waser Mary Sue
Published: August 2010

Abstract and Summary

Ichneumia are nocturnal, insectivorous, solitary, but in high‐density populations live in clans within which several females and their offspring forage independently in common home ranges. It is likely, though as yet unproven, that clans are matrilines and are formed when some female offspring fail to disperse from the natal home range. The social structure of Ichneumia suggests that social groups in other viverrids arose when selection simultaneously favored two independent behavioral tendencies: (1) natal philopatry (failure of some young to disperse), and (2) gregariousness. Prey characteristics are likely to have favored the former, safety from predators the latter. In this view, only the former process has been operative in Ichneumia.

Lamprecht (1981, p. 178), summarizing data bearing on the advantages of group hunting in canids, felids, and hyaenids, has recently concluded that even among larger carnivores groups are sometimes “adapted to problems quite unconnected with hunting and feeding, such as protection from predators, or competing for territories or mates”. Evidently, his generalization fits group‐living viverrids as well. Ichneumia social structure suggests a route by which selection might have produced more complex viverrid societies.

Weißschwanzmangusten sind nachtaktive Insektenfresser und leben solitär. Bei hoher Populationsdichte jedoch schließen sich mehrere Weibchen mit Nachkommen zu Clans zusammen und gehen zwar getrenntaber im gleichen Streifgebiet auf Nahrungssuche. Vermutlich sind diese Clans matrilinear verwandt und entstehen, wenn einige Töchter nicht aus dem mütterlichen Gebiet abwandern.

Die Sozialstruktur der Weißschwanzmanguste läßt vermuten, daß die festen Sozietäten anderer Viverriden entstanden, wenn die Selektion Gruppen prämiierte und das Abwandern der Nachkommen erschwerte; Feindvermeidung scheint für das erstere, Nahrungserwerb für das letztere verantwortlich. Bei der Weißschwanzmanguste wirkt nur der Nahrungsfaktor.

Wie weit Viverriden in ein allgemeines Gruppenbildungs‐Schema der Carnivoren passen, wird erörtert.
A Comparison of Frequency of Intra‐colony Aggressive Behaviours among Five Species of Polistine Wasps (Hymenoptera: Vespidae)
Authors: Itô Yosiaki
Published: August 2010

Abstract and Summary

Social behaviours among adult females on multifemale‐nests of five paper wasp species were observed in Panama and Okinawa. Polistes Canadensis females showed, during the pre‐emergence period, severe overt dominance or aggressive behaviours at a rate significantly higher than four other species. The interrelationship among females of Ropalidia fasciata was notably mild during the pre‐emergence period. In Mischocyttarus angulatus and M. basimacula the relationships were also mild during the pre‐emergence period but became aggressive in the post‐emergence period. Polistes versicolor maintained its mild relationship through post‐emergence period. Typical depressive posture shown by subordinates of P. Canadensis is considered to be a ritualized behaviour which diminishes intracolony aggression. Evolution of pleometrosis (multiple egg‐layers on a nest) with rudimentary caste differentiation in social wasps through mutualism and parental manipulation was discussed.

An fünf Faltenwespenarten wurde das Sozialverhalten adulter Weibchen in Vielweibchennestern in Panama und in Okinawa beobachtet. Während der Vorschlupfphase zeigten Polistes canadensis‐Weibchen deutliches Dominanzoder aggressives Verhalten signifikant häufiger als bei den anderen vier beobachteten Arten. Weibchen der Art Ropalidia fasciata sind während der Vorschlupfphase untereinander auffallend unaggressiv. Ebenso unaggressiv war die Beziehung unter den Weibchen der Arten Mischocyttarus angulatus und M. basimacula; sie wurden jedoch während der Nachschlupfphase aggressiv. Polistes versicolor blieb während der Nachschlupfphase unaggressiv. Die typische Beschwichtigungsgebärde von subdominanten P. canadensis‐Weibdien sehen wir als ritualisiertes Verhalten an, das die Aggression innerhalb der Kolonie verringert. Die Evolution von Pleometrosis (d. i. mehrere Weibchen legen in ein Nest) bei sozialen Wespen mit rudimentärer Kastendifferenzierung durch Mutualismus und elterliche Manipulation wird diskutiert.
The Pooling Fallacy: Problems Arising when Individuals Contribute More than One Observation to the Data Set
Authors: Machlis L. , Dodd P. W. D. , Fentress J. C.
Published: August 2010

Abstract and Summary

In ethological studies it is common practice to obtain multiple observations on each individual in a sample and to Pool these observations into one data set for statistical analysis. In this paper we argue that this procedure reflects a fundamental error in the logic underlying random sampling since it implicitly assumes that the purpose of data gathering in ethology is to obtain large “samples of behaviour” rather than samples of behaviour from a large number of individuals. That is, it is assumed that the reliability of estimates of population parameters can be increased by obtaining additional observations on individuals already in the sample rather than by increasing the number of individuals observed. Using a Monte Carlo simulation we show that when such Pooled data sets are analysed statistically, the probability of rejecting a true null hypothesis is almost always substantially greater than the stated alpha level.

In ethologischen Untersuchungen ist es üblich, von jedem Individuum einer Stichprobe mehrere Meßwerte zu gewinnen und für die statistische Analyse die Werte aller Individuen zu einer einzigen Stichprobe zu vereinigen („pooling”). Diesem Verfahren liegt, wie in der vorliegenden Arbeit gezeigt wird, ein fundamentaler Irrtum bezüglich der zufälligen Stichprobenauswahl zugrunde, da implizit davon ausgegangen wird, man müsse große Stichproben der Verhaltensweisen anstatt Stichproben des Verhaltens möglichst vieler Individuen sammeln. Damit wird angenommen, daß Populationsparameter zuverlässiger geschätzt werden können, wenn man mehr Beobachtungen am bereits in der Stichprobe vertretenen Individuen macht als wenn man zusätzliche Individuen beobachtet.

Mit einer Monte–Carlo–Simulation wird gezeigt, daß die statistische Analyse solcher zusammengesetzter („pooled”) Stichproben fast immer eine wesentlich großere als die angegebene Irrtumswahrscheinlichkeit für („type I error”) ergibt.
Social Behavior of the Huemul (Hippocamelus bisulcus) during the Breeding Season
Authors: Povilitis A.
Published: August 2010

Abstract and Summary

Behavior of the huemul, Hippocamelus bisulcus, was studied during the fall rut in 1980, 1982, and 1983 at the Rio Claro, Chile. Data were acquired on group size and composition and on social relationships among tour bucks and three does, identified by natural markings. A range of behaviors involving interactions between animals of different sex and age groups were described and quantified. Huemul bucks, in tending individual does over extended periods of time, seldom courted more than one female. Estrus dates for one doc were determined in 1982 and 1983.

Das Verhalten des Huemul (Hippocamelus bisulcus) in der Paarungszeit wurde 1980, 1982 und 1983 am Rio Claro, Chile, untersucht. Direkt beobachtet wurde über 400 h lang in einem 275 ha größen Gebiet, das von 9 Tieren bewohnt war.

71% der Gruppen bestanden aus Paaren mit jungen oder rangtiefen zusätzlichen Männchen; die Gruppen zählten 1–5 Tiere.

Männchen warben um Weibchen von Mitte Februar bis Mitte April, schwächer bis zur ersten Juniwoche. Männchen schnuppern heftig an den Weibchen, berühren und begatten sie, folgen ihnen, flehmen, treiben usw. Weibchen weichen zunächst im Zickzack aus, laufen hinter Hindernisse oder unter diesen durch. Männchen versuchen selten, ein Weibchen von der Annäherung an ein anderes Männchen abzuhalten.

Balzverhalten vor demselben Weibchen erreicht alle 10–12 Tage einen Höhepunkt, wohl im Zusammenhang mit der Follikelreifung. 22–16 Tage vor der Begattung warb ein dominantes Männchen ausschließlich um dieses Weibchen, später kamen andere Männchen dazu. Rivalen werden angegriffen und vertrieben; Drohungen oder Imponierstellungen sind wenig ausgeprägt, Ritualkämpfe selten. Männchen setzen Duftmarken, indem sie Gesicht und Kopf an Vegetation reiben.

Männchen und Weibchen bleiben lange beieinander, zur Kopula kommen vornehmlich die dominanten Männchen, „heimliche” Begattungen von rangtiefen Männchen kommen vor. Die Männchen scheinen polygyn zu sein, doch gibt es umständehalber — besonders wegen geringer Populationsdichte — monogame Paare.
Individual Recognition of Helpers by the Breeders in the Cichlid Fish Lamprologus brichardi (Poll, 1974)
Authors: Hert Eva
Published: August 2010

Abstract and Summary

In the cichlid Lamprologus brichardi young fish help to rear their parents' new broods and defend the territory. Parents must be able to distinguish these broodcare helpers from other young fish to guard against egg predators and reproductive parasites. Various possible means of helper identification are discussed.

Parents attacked their own helpers less often than strange young fish of the same size in standardized test conditions. Strange helpers were attacked more often than own helpers but less often than strange non‐helping young. Helpers behaved more submissively than other young of the same size not living in family groups. Simultaneous choice tests were carried out using one‐way reflecting foil to prevent exposed fish from seeing hence reacting to the breeding pair, yet the breeding pair obviously attacked its own helpers less often. Strange helpers and other strange controls were treated in the same way as each other. It was concluded that breeders recognize their helpers individually.

Beim Cichliden Lamprologus brichardi beteiligen sich Jungfische an der Aufzucht von Gelegen ihrer Eltern und an der Revierverteidigung. Eltern müssen diese Brutpflege‐Helfer von anderen Jungfischen unterscheiden können, um sich vor Eiräubern und Fortpflanzungsparasiten zu schützen. Verschiedene Möglichkeiten für die Helfer‐Identifizierung werden diskutiert.

Unter standardisierten Testbedingungen griffen Eltern ihre eigenen Heifer weniger an als gleichgroße fremde Jungfische. Fremde Heifer wurden zwar mehr als eigene, aber weniger als andere fremde Jungfische angegriffen. Heifer verhielten sich aber auch submissiver als gleichgroße Jungfische, die nicht in Familienverbänden lebten. In Simultan‐Wahl‐Experimenten wurde mit Hilfe von einseitig verspiegelten Folien die Sicht der Testfische zum Brutpaar versperrt. In dieser Situation unterschieden sich die Testfische in ihrem Verhalten nicht voneinander. Das Brutpaar griff dennoch den eigenen Heifer deutlich seltener an. Zwischen fremden Helfern und fremden Kontrollfischen unterschied es nicht mehr. Daraus wurde geschlossen, daß Brutpaare ihre Heifer individuell erkennen.
Two Modal Action Patterns with a Continuous Temporal Distribution
Authors: Bond Alan B. , Barlow George W. , Rogers William
Published: August 2010

Abstract and Summary

Most methods of quantitative analysis of animal behavior assume that action patterns can be unambiguously classified into discrete, exclusive categories. This is not invariably the case. The digging behavior of the Midas cichlid (Cichlasoma citrinellum), for example, exhibits two functionally distinct modalities, scoop and pick, that intergrade continuously in form but are separable probabilistically. We present a technique for analyzing such behaviors that provides a reliable basis for formulating and verifying categories and allows a quantitative assessment of functional dissimilarity.

Die meisten Methoden quantitativer Verhaltensanalysen setzen eindeutige Klassifizierung der Verhaltensweisen in sich wechselseitig ausschließende Kategorien voraus. Die sind aber nicht immer gegeben. Das Graben des Midas‐Cichliden Cichlasoma citrinellum wird in zwei funktional verschiedenen Weisen ausgeführt, „Schaufeln” und „Picken”, die der Form nach ineinander übergehen und nur statistisch unterscheidbar sind. Eine Analysetechnik für solche Fälle wird vorgestellt, die eine verläßliche Basis für eine Kategorienbildung bietet und eine quantitative Einschätzung der funktionalen Unterschiede dieser Verhaltensweisen erlaubt. Die nachfolgende Faktorenanalyse bestätigte die funktionale Unterscheidung der beiden Endhandlungen (Modal Action Patterns). Das Verfahren scheint allgemein anwendbar.
Initial Orientation and Homing in Workers of Polistes gallicus (L.) (Hymenoptera, Vespidae)
Authors: Ugolini Alberto
Published: August 2010

Abstract and Summary

Workers of Polistes gallicus were displaced in transparent plexiglass test tubes, which allowed them sight of the sky, sun and landscape and then released, in a series of trials at various distances from the nests, in the open and in confined conditions (using an arena) to assess their ability of initial orientation and homing.

Results show that the workers are able to show the correct homeward direction independently of release distance, vision of the surrounding landscape and motivation. Homing times and homing performance, on the other hand, depend on release distance and motivation. The possibility that information gained during displacement plays a part in initial orientation is also discussed.

Arbeiterinnen von Feldwespen (Polistes gallicus) wurden in verschiedenen Abständen vom Nest (50, 200, 1000, 1500, 2000 m) sowohl frei als auch in einer kreisförmigen Arena so aufgelassen, daß sie nur Sicht auf den Himmel hatten. Sie fanden auch ohne Sicht der Landschaft gut (statistisch gesichert) nach Hause. Heimkehrzeiten und Zahl der heimkehrenden Wespen waren sowohl von der Entfernung wie auch von der Motivation abhängig. Vermutlich sammelt das Tier während der Versetzung Informationen, die für seine zielgerichtete Orientierung am Auflaßort wichtig sind.
Interspecific Differences in the Ontogeny of Feeding Behaviour in Two Species of Centrarchid Fish
Authors: Brown Joseph A. , Colgan Patrick W.
Published: August 2010

Abstract and Summary

We compared the ontogeny of feeding in two centrarchid species and hypothesised that the ontogeny of early feeding in the black crappie, Pomoxis nigromaculatus, would differ from that of the smallmouth bass, Micropterus dolomieui, and that the smaller black crappie fry would perform certain of the feeding MAPs (modal action patterns) at a higher frequency and for a longer period of time than the larger smallmouth bass fry. Under laboratory conditions crappie fry performed significantly more Fixates, Lunges, and Snaps than smallmouth fry. These three MAPs also remained in the feeding repertoire of the crappie two weeks longer than in the smallmouth repertoire. The size of the young fish at the onset of exogenous feeding influenced their early feeding behaviour.

Wir haben die Ontogenese des Fressens von zwei Sonnenbarsch‐Arten (Pomoxis nigromaculatus und Micropterus dolomieui) in Laboraufzuchten verglichen. Wir sagten voraus, daß die kleinere Fischbrut des dunklen Süßwasserbarsches bestimmte Verhaltensweisen häufiger und während längerer Zeit ausführen würde als der Flußbarsch. Die kleinere Brut des P. nigromaculatus zeigt bedeutend mehr Schnappen, Vorstoßen und Festhalten als die von M. dolomieui. Die drei Verhaltensweisen kommen bei P. nigromaculatus zwei Wochen länger vor als bei M. dolomieui. Die Größe der jungen Fische beeinflußt ihr Verhalten bei der Nahrungsaufnahme.
Compatibility of Male and Female Sexual Behaviour in Macaca arctoides
Authors: Linnankoski I. , Leinonen L. M.
Published: August 2010

Abstract and Summary

This report describes factors influencing the attainment of orgasm in the stump‐tailed macaque in the laboratory. In the male, penile stimulation during copulation was not a sufficient condition for orgasm to occur; successful copulation had to be preceded by a high level of excitement triggered by various psychosocial factors. In the female, stereotypic signs of high sexual excitement were invariably displayed during copulation at the time of male orgasm and also during homosexual interactions which did not provide genital stimulation. The observations suggest that female orgasm results from high responsiveness to the overall behaviour of the excited partner.

Dieser Bericht beschreibt Faktoren, die bei im Labor lebenden Stummelschwanz‐Makaken (Macaca arctoides) zum Orgasmus führen.

Beim Männchen war die Penisreizung während der Kopulation keine ausreichende Bedingung für das Auftreten eines Orgasmus; einer erfolgreichen Kopulation muß ein hoher Grad an Erregung, ausgelöst durch verschiedene psychosoziale Faktoren, vorausgehen. Das Weibchen zeigte gleichbleibend stereotype Zeichen hoher sexueller Erregung während der Kopulation zum Zeitpunkt des männlichen Orgasmus und ebenso während homosexueller Interaktionen ohne genitale Reizung. Die Beobachtungen scheinen darauf hinzuweisen, daß das Weibchen während der Kopulation infolge seiner hohen Empfänglichkeit für das Gesamtverhalten des erregten Partners mit der Ejakulation des Männchens einen Orgasmus erfährt.
Distance Call Duets in Bar‐headed Geese (Anser indicus): Co‐operation through Visual Relief of the Partner?
Authors: Lamprecht Jürg , Kaiser Alexander , Peters Anne , Kirchgessner Cordula
Published: August 2010

A new example of duetting is reported for a waterfowl species. Semi‐captive pairs of bar‐headed geese (Anser indicus), whose 2–9 days old young were removed, uttered short, coarse distance calls every 1 or 2 s while searching for them. The males often called a fraction of a s after their mates. The result was a duet. The females did not answer the males' calls.

The context in which these duets occur is also new: the parent birds remain within a few m of each other to call their goslings and stop calling as soon as they have found them. This, the behaviour of the goslings, the lack of observed mate‐changes and the fact that only the male responds make it unlikely that the function of these duets is territorial advertisement, avoidance of call overlap, mate‐guarding, strengthening of the pair‐bond or synchronization of activities, functions which have been suggested for various duets in birds and primates.

We suggest that male response to the female's distance calls relieves her from visually monitoring her mate's whereabouts. Thus the female, who searches more actively, can concentrate fully on finding the offspring. Visual relief of the partner could also be important in duets of other species.

Für Anatiden sind bisher nur Triumphzeremonien als Duette beschrieben. Freifliegend gehaltene Streifenganspaare (Anser indicus), denen die 2–9 Tage alten Jungen weggefangen wurden, äußerten bei der Suche nach ihnen anhaltend kurze, rauhe “Distanzrufe” in Abständen von 1–2 s. Dabei riefen die Männchen sehr oft Sekundenbruchteile nach ihren Weibchen, so daß Ruf‐Duette zustande kamen. Die Weibchen antworteten nicht nachweisbar auf die Rufe der Männchen. Neu an diesen Duetten ist auch der Kontext: Die Eltervögel, die nur wenige m voneinander entfernt sind, rufen nach ihren Jungen (und hören auf, sobald sie sie gefunden haben). Die Begleitumstände, das Verhalten der Gössel, das Fehlen von Partnerwechseln und der Befund, daß nur das Männchen antwortet, machen eine Funktion dieses Duettierens im Rahmen der Revieranzeige, des Vermeidens von Lautüberlappung, des Partner‐Bewachens, des Stärkens der Paarbindung und der Synchronisation der Paarpartner unwahrscheinlich. Vermutlich dient es der Entlastung des bei der Gösselsuche visuell stark engagierten Weibchens vom ständigen optischen Überwachen des Partners, so daß es — das aktiver sucht — sich mit ungeteilter Aufmerksamkeit dem für beide Partner wichtigen Orten der Jungen widmen kann. Visuelle Entlastung des Partners könnte auch bei manchen Duetten anderer Arten eine Rolle spielen.
Social Guidance of Vocal Learning by Female Cowbirds: Validating its Functional Significance
Authors: West Meredith J. , King Andrew P.
Published: August 2010

Juvenile male M. a. ater cowbirds, who have never heard other male cowbirds sing, develop distinctively different repertoires when housed with M. a. ater females from their own area versus M. a. obscurus females from a distant population. Because female cowbirds do not sing, the differences in the males' songs do not arise through vocal imitation. Here we provide data demonstrating that the songs of female‐housed males are functionally, as well as acoustically, distinctive. The songs of 8 groups of males were tested where the groups differed by age of singer, acoustic experience, and identity of social companion. The playback results demonstrate that non‐singing female cowbirds not only stimulate the male to modify song content, but song potency. As such, they demonstrate the critical role female cowbirds may assume in the proximate and ultimate regulation of vocal development.
Sexual Differences in Offspring Defense in a Monogamous Cichlid Fish
Authors: Itzkowitz M.
Published: August 2010

Solitary male and female Texas cichlids, Cichlasoma cyanoguttatum employ different tactics when defending their offspring. Males emphasize the lateral display against an intruder and make infrequent return visits to the young while the intruder is present. The female is more likely to attack, attempting to bite the intruder and also making frequent return visits to the offspring. These differences disappear with increasing age of the offspring as the male becomes more like the female with more violent attacks. Both defense systems appear effective, in the short term, against intruders.
Sexual Behaviour of Sumatran Long‐tailed Macaques (Macaca fascicularis)
Authors: van Noordwijk Maria A.
Published: August 2010

The sexual behaviour of wild long‐tailed macaques (Macaca fascicularis) was studied in the Gunung Leuser National Park, Sumatra, Indonesia. All females showed some swelling of the sexual skin, but the frequency and maximum size of the swelling decreased with age. The frequency of copulations and consortships for a given female increased with increasing degree of swelling or coloration. No regular cycles could be found in the occurrence of swellings, copulations and consortships. Periods for which a female had consortships tended to be long (up to 5–6 weeks on end). These two results suggest that in the wild the predictability of the moment of ovulation is very low. The consortships were not exclusive: both the male and the female occasionally copulated with others. All females had many different male partners and, as ovulation signalling was not clear, none of these males could have any certainty about paternity of a female's offspring. Yet, the highest‐ranking males probably had the best chances to father children because they were more often involved in sexual interaction (both copulations and consortships), especially around the estimated date of conception. This does not hold for the nulliparous females who were virtually ignored by the higher‐ranking males. Consortships were occasionally actively maintained by the female, for whom a direct advantage of consorting might be an increased safety against conspecifics and predators. One advantage of mating with many different males might be a reduced risk of infanticide.
The Behavioural Dynamics of Great Tits (Parus major) Approaching a Predator
Authors: Curio E. , Regelmann K.
Published: August 2010

There is a deadly risk of mobbing at a predator (= approaching it, usually alarm calling at the same time), as evidenced by a long list of published and unpublished accounts of a fatal or nearly fatal outcome for the prey involved. We examined in four predator‐related danger situations (two raptors [Strix aluco, Accipiter nisus], a raptor [Glaucidium perlatum] + taped mobbing chorus, mobbing chorus only) the ways in which the multi‐dimensional mobbing behaviour of parent great tits (Parus major) with nestlings tends to reflect the spatial properties of a gradient of risk around the live predator viz. the acoustic danger stimulus. The analysis was based on the factual premise that predation risk grows in some unknown way with proximity to danger. Great tits appear to mitigate their risk by at least 8 spatio‐temporal characteristics of their moves towards and away from danger, resulting in a net approach. While thus advancing, the birds commonly engage in approach moves of ever decreasing length and in an increasingly higher calling rate. The latter relationship suggests that risk increases continuously with proximity. The dependence of the calling rate on predator distance is discussed in terms of overloading the visual‐auditory channel capacity of the harassed predator and of advertising to it powers of escape in order to discourage attack.

Während Beutetiere sich alarmrufend nahe um einen Räuber scharen, setzen sie sich dem Risiko aus, von ihm getötet zu werden; dies belegt eine lange Reihe schon veröffentlichter und hier erstmals genannter Begegnungen mit tödlichem oder fast tödlichem Ausgang. Wir untersuchten, ob und wie Kohlmeisen (Parus major) mit Nestlingen in einer von vier Feindsituationen [zwei Greifvögel (Strix aluco, Accipiter nisus); ein Greif (Glaucidium perlatum) mit Tonband‐Mischalarm; dieser Alarm allein] in ihrem vieldimensionalen Alarmverhalten den räumlichen Risikogradienten um den Räuber bzw. um die nichtklassifizierbare Gefahr widerspiegeln. Die Analyse fußte auf der belegten Voraussetzung, daß das Feindrisiko mit der Nähe zur Gefahr irgendwie wächst. Kohlmeisen mindern danach ihr tödliches Risiko auf mindestens achterlei Weise während ihres schrittweisen, vor– und zurückweichenden Eindringens auf den Feind. Während sie so vorrücken, verkürzen sie überwiegend die Länge ihrer Vorwärtsflüge zusehends und erhöhen ihre Alarmrufrate. Diese Ruf‐Abstandsbeziehung läßt auf eine kontinuierliche (d. h. nicht sprung‐hafte) Zunahme des Risikos mit zunehmender Räubernähe schließen. Die Abhängigkeit der Rufrate von dem Feindabstand wird im Lichte zweier hypothetischer Mechanismen erörtert: zum einen der Begrenzung des auditorisch‐visuellen Systems des Räubers, zum anderen der an ihn gerichteten Mitteilung über die Güte der Fluchtfähigkeit des Rufers im Fall eines Angriffs.
Parturition in American Bison: Precocity and Systematic Variation in Cow Isolation
Authors: Lott Dale F. , Galland John C.
Published: August 2010

Abstract and Summary

We observed the birth of 16 American bison calves. Parturition was rapid and the calves were unusually precocial. Parturition occurred in early to mid‐afternoon. In an open grassland habitat, 9 of 11 cows remained in groups to give birth. In contrast, 5 of 6 cows in a rugged oak‐woodland habitat gave birth in isolation.

Waldadaptierte Huftiere gehen gewöhnlich einzeln in Vegetation, um zu gebären, wohl um Begegnungen mit Raubtieren zu verringern. An offenes Grasland adaptierte Arten gebären schnell und haben besonders frühreife Junge. Gruppen sind wahrscheinlich die beste Deckung im Habitat; aber das Gebären in Gruppen führt auch dazu, daß Mütter sich täuschen und fremde Säuglinge adoptieren. Amerikanische Bisons lebten vor allem auf offenem Grasland. Sie gebären schnell, und Bisonjunge sind frühreifer als die meisten Huftiere, ausgenommen das Gnu. Sie gebären meist am frühen Nachmittag. Die näheren Umstände des Gebärens waren in den zwei beobachteten Populationen verschieden. 9 von 11 Kühen in vorwiegend offenem Habitat gebaren in einer Gruppe; 5 von 6 Kühen in teils bewaldetem Habitat gebaren einzeln unter hoher Vegetation. Kindsverwechslungen sind wahrscheinlich selten. Die Bison‐kälber, die wir beobachteten, näherten sich sofort ihren Müttern und blieben dann in ihrer Nähe.
Effect of Male Proximity on Vaginal Marking by the Female Syrian Hamster (Mesocricetus auratus)
Authors: Steel Elizabeth
Published: August 2010

Abstract and Summary

Vaginal marking by female hamsters is more frequent in the presence of a male than when the female is alone; this is so on each of the three dioestrous days of the oestrous cycle. With a male present, marking frequency on Day 4 is about four times greater than on Day 2 or 3 of dioestrus. On Day 4, vaginal marking is correlated with male proximity and is greatest when the male is actively following the female. Vaginal marking is closely associated in time with the female moving away from the male, and particularly with rapid approach‐withdrawal by the female.

Discussion centres on the function of vaginal marking. Vaginal secretion has at least two chemical fractions which have different effects on the male. It is likely that the context in which the male samples the vaginal secretion may modify the information that is transferred from the female.
Communication of Status in the Social Wasp Polistes fuscatus (Hymenoptera: Vespidae)
Authors: Downing H. A. , Jeanne R. L.
Published: August 2010

Communication of status was demonstrated in females of the paper wasp, Polistes fuscatus. Wasps directed more aggression toward subordinates which were similar in status to themselves than toward dominants or low ranked subordinates. Chemical cues originating from both the head and the ovaries communicate status. The hypothesis that lateral vibrations are used by the queen to communicate her dominance to nestmates was not supported by our findings. No correlation was found between the amount of light body coloration and dominance status. Queens that had been tethered and were thus unable to pursue subordinates aggressively still communicated their status but their dominant rank in the colony was often affected.
The Function of the Pika Short Call in Individual Recognition
Authors: Conner Douglas A.
Published: August 2010

Abstract and Summary

Two populations of individually marked pikas (Ochotona princeps) were studied on Niwot Ridge, Boulder County, Colorado, U.S.A., to determine if these lagomorphs are able to, and actually do, recognize other individuals through the use of vocal cues contained in the short call. Discriminant function analysis demonstrated that short calls are individually distinct in structure. Furthermore, pikas responded differentially to naturally occurring calls from different individuals and recognition appears to be possible solely through the use of vocal cues contained within the short call.

Pikas also discriminated between playbacks of familiar and unfamiliar short calls. The strength of response appears related to the level of competition and the relative amount of threat that a familiar or unfamiliar pika represents to the responding individual.
Vigilant Behaviour and Shoal Size in Minnows
Authors: Magurran A. E. , Oulton W. J. , Pitcher T. J.
Published: August 2010

Abstract and Summary

The aim of this work was to investigate the relationship between shoal size and vigilance. The behaviour of minnows (Phoxinus phoxinus) foraging on an artificial food patch during the simulated stalking approach of a model predator (pike: Esox lucius) was recorded for shoals of 20, 12, 6 and 3 fish. Minnows in large shoals reduced their foraging sooner but remained feeding on the patch longer than in small shoals. The relatively late reaction of small shoals to the model and the rapid cessation of feeding once the predator was detected, indicates that small shoals were less vigilant than large shoals. The gradual reduction of foraging in large shoals was accompanied by an increasing number of investigative approaches in which individuals monitored the model's approach. This enabled minnows in larger shoals to balance more efficiently the conflicting demands of feeding and watching for predators.
Verhaltensanalysen zum Sozialspiel von Iltisfrettchen (Mustela putorius f. Juro)
Authors: Diener Alfred
Published: August 2010

Abstract and Summary

Behaviour Analysis of Polecat Ferrets during Social Play

The article deals with the social play of polecat ferrets (Mustela putorius f. furo). The coordinations in playful romping are compared with parallel functional behaviour patterns. The behaviour shown in play is less strictly coordinated and orientated than the corresponding behaviour sequences in fighting and mating. Some of the forms of behaviour are more intensive and longer lasting in a serious context than they are in play. In the ontogenesis of social play both continuity and stages of development can be differentiated. The basic patterns of attack and defence are displayed in complete form shortly after the eyes open. The deliberate gripping of the nape of the neck develops gradually. It is probable that this development is partly dependent on learning processes.

The social experience of young polecat ferrets affects the degree of their play motivation. During the experiment, animals which had been reared alone played together more than three times as much as those reared socially. The withholding of social experience apparently causes a drop in the threshold values of many sequences of play behaviour.

In play, sex difference affects both the readiness to act and the frequency of many forms of behaviour. In general males play more frequently than females. In encounters between opposite sexes the males play offensively and the females defensively or passively. It is assumed that social play serves to develop forms of behaviour which will later be of decisive importance in social behaviour generally and in sexual behaviour in particular.
Dominance as a Predictor of Cofoundress Disappearance Order in Social Wasps (Polistes fuscatus)
Authors: Pfennig David W. , Klahn Jeff E.
Published: August 2010

Abstract and Summary

Paper wasp foundress longevity was examined by censusing throughout one colony cycle 29 multiple foundress queens, 43 multiple foundress subordinates, and 56 single foundresses that were nesting in artificial nestboxes in the same field habitat. At the end of the census period when most colonies were in a state of decline, all of the multiple foundress queens, 32% of the single foundresses, and 19% of the subordinate cofoundresses remained with their colony. Half of the subordinates disappeared within 15 days after the first workers eclosed and before most reproductive eggs were laid. On colonies with more than one subordinate cofoundress, the closer in rank a cofoundress was to the queen, the sooner the cofoundress disappeared after the workers eclosed. The queen and her worker offspring may increase their inclusive fitnesses by selectively ejecting the highly ranked cofoundresses, which pose the greatest threat to the queen's reproductive domination. Subordinate longevity appears to be influenced more by intracolony reproductive conflict than by foraging‐related mortality.
The Evolution of Bower‐building and the Assessment of Male Quality
Authors: Borgia Gerald , Pruett‐Jones Stephen G. , Pruett‐Jones Melinda A.
Published: August 2010

Abstract and Summary

A hypothesis is proposed for explaining the evolution of display courts in birds. We suggest that males who show ownership of display courts are better able to inform females of their high dominance status, which is an indicator of their quality as a sire. The elaborate display structures of bowerbirds are viewed as an extreme example of selection to show ownership of these “markers”. Specific problems with the evolution of bowers are considered.
How Turtles Find the Sea
Authors: Mrosovsky N. , Kingsmiix S. F.
Published: August 2010

Abstract and Summary

Hatchling turtles, after emerging from their nests on the beach, move towards the sea. One explanation of this sea‐finding ability is that there is a complex phototropotactic reaction to light; this initiates turning until sub‐components of the system receive equal input. Another explanation is that the direction of peak excitation is located instantaneously and that the turtles then head in that direction. This paper reports new experiments on the behaviour of loggerhead turtles (Caretta caretta) wearing partial blindfolds: their poor orientation, even after several hours time for adaptation to the blindfolds, supports the phototropotaxis hypothesis. Data on loggerhead, leatherback (Dermochelys coriacea) and green turtle (Chelonia mydas) hatchlings released under clear skies confirm that the position of the sun does influence orientation. Experiments on loggerheads with wax paper over their eyes show that form vision is not essential for sea‐finding. The possibility of mechanisms additional to and redundant with a complex phototropotactic system or a direction locating system are considered but rejected as unlikely.
Irritant contact dermatitis: A review
Authors: Slodownik Dan , Lee Adriene , Nixon Rosemary
Published: August 2010

Irritant contact dermatitis is the most common form of contact dermatitis, and yet is often overlooked. Recent progress in understanding the pathogenesis has reignited the interest of clinicians in this area of dermatology. Irritant contact dermatitis is not a homogenous entity, but rather a number of subtypes contributing to different clinical presentations. The diagnosis of irritant contact dermatitis is often clinical, and may only be possible after the exclusion of allergic contact dermatitis with patch testing. There is no readily available diagnostic test. There is an incomplete understanding of the factors which lead to the development of cumulative irritant contact dermatitis and persistent postoccupational dermatitis. We have used the experience from our tertiary referral occupational dermatology clinic to illustrate various aspects of irritant contact dermatitis, and to highlight the difficulty sometimes encountered in making this diagnosis. We believe that increased awareness of the often pivotal role of irritant contact dermatitis, as well as all the other factors contributing to occupational dermatitis, will lead to improvement in outcomes for patients.
Narrowband UVB therapy as an effective treatment for Schamberg's disease
Authors: Lasocki Anita L , Kelly Robert I
Published: August 2010

A 33‐year‐old man presented with a 3‐month history of a widespread pigmented purpuric eruption over his trunk and limbs. The clinical presentation and histology were consistent with a diagnosis of Schamberg's disease. The rash initially cleared following a short course of oral prednisolone at 25 mg daily for 3 weeks, which was weaned over the subsequent 4 weeks. Topical mometasone furoate ointment 0.1% daily was also applied to active areas. The rash recurred when prednisolone was reduced to below 5 mg per day. To prevent a further recurrence with weaning prednisolone, narrowband UVB therapy was commenced three times per week. The patient was continued on UV therapy over the next 5 months. The rash would flare after 2 to 3 weeks without treatment. The frequency of UV therapy was weaned and the patient remained clear on as little as one treatment every 2 weeks. Any further reduction, however, was associated with a recurrence. Narrowband UVB therapy should be considered for difficult or persistent cases of pigmented purpuric eruption.
Aquagenic wrinkling of the palms in a cystic fibrosis carrier
Authors: Gild Rochelle , Clay Christopher D
Published: August 2010

A 16‐year‐old girl presented with a 3‐year history of painful swelling and wrinkling of her palms on exposure to water. Physical examination, after less than 2 min of immersion, showed thickening and exaggerated wrinkling of the palms giving a whitish pebbly appearance. Aquagenic wrinkling of the palms was diagnosed. The patient was tested for the common cystic fibrosis mutations, and was found to be heterozygous for the arg117His cystic fibrosis mutation. Her sweat test was normal.