bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Novelty On Taste-Avoidance Learning in Chicks
Authors: Roper T.J.
Published: April 2008

Five experiments were conducted to investigate the effect of novelty on visually-mediated taste-avoidance learning in domestic chicks. In experiments l a and b, chicks were reared with either uncoloured or blue fluid in their home cages, and then required to discriminate between blue and uncoloured fluids that were either palatable or unpalatable (quinine-adulterated). For some chicks the distasteful fluid was novel in appearance, for others it was familiar. In both experiments chicks readily discriminated between a novel unpalatable fluid and a familiar palatable one, but failed to discriminate between a familiar unpalatable fluid and a novel palatable one. This failure to discriminate resulted from avoidance of the palatable fluid. In neither experiment did novelty enhance the rate of avoidance learning. Experiment 2 tested more directly the effect of novelty on speed of avoidance learning. Chicks were reared on either red or blue palatable fluid, then tested with either red or blue distasteful fluid. Avoidance learning was more rapid when the distasteful fluid was novel in colour, in both red-reared and blue-reared chicks. Experiment 3 investigated the inability of chicks to discriminate between a familiar unpalatable fluid and a novel palatable one, demonstrated in experiment 1. Chicks were required to discriminate between different-coloured palatable and unpalatable fluids when both were familiar in appearance (experiment 3a) or when both were novel (experiment 3b). Discrimination occurred in the first case but not in the second. In addition, avoidance learning was slower when both unpalatable fluids were familiar. I conclude that (a) novelty faciliates visually-mediated taste-avoidance learning in chicks and (b) the failure of chicks to discriminate a novel palatable fluid from a familiar unpalatable one depends on the relative novelty of the palatable fluid and not on the relative familiarity of the unpalatable one. The results are discussed in the context of warning coloration and are explained in terms of an interaction between unlearned and learned avoidance tendencies.
Thermoregulatory Behaviour of Rock Lizards in Response To Tail Loss
Authors: Martin José , Salvador Alfredo
Published: April 2008

The consequences of tail loss on the thermal biology of high-altitude rock lizards (Lacerta monticola) were studied by comparing field body temperatures, selected body temperatures in a gradient, and behavioural patterns of thermoregulation of tailed and tailless lizards in the field. Neither field nor selected body temperatures differed significantly between these groups. Time spent basking, mean duration of basking, and basking frequency did not differ between tailed and tailless lizards. Tailless lizards seemingly adjusted for running impairment by using rocks to a greater extent than did tailed lizards, and low morning body temperatures by increasing maximal duration of basking periods and keeping shorter distances to the nearest refuge. Tailless lizards modify thermoregulatory behaviour, but obtain the same thermoregulatory precision as tailed lizards, possibly allowing maximization of physiological processes linked to tail regeneration.
Short Duration Time Constant Associated With Chewing in the Guinea Pig
Authors: Gerstner Geoffrey E. , Goldberg Louis J.
Published: April 2008

Previous investigations have reported a time constant on the order of a few seconds associated with temporal perception in humans, and with movement patterns in humans and other mammalian species. It has been suggested that the time constant represents the operation of a physiological oscillatory mechanism that is common among many mammalian species. However, the time constant has not yet been observed in laboratory animals; therefore, there is no laboratory-based behavior paradigm upon which studies into the physiological nature of this time constant can be based. Because of our familiarity with guinea pig feeding, the current study was undertaken in order to find evidence of the time constant in feeding-associated activities of guinea pigs. Eleven guinea pigs were starved for a 24 hr period, then placed individually into a rich behavioral arena for 30 min, during which time they were videotaped continuously while they roamed freely. The animals inevitably ate during these videotape sessions, and a detailed analysis of chewing parameters was done. It was found that chewing typically occurs in bursts, and that the median burst duration was 1.03 - 3.46 s for individual animals. Chewing burst durations were similar to the durations of many movement patterns in other species including humans. This provides further support for the hypothesis that there is a highly conserved time constant associated with movement patterns in mammals. It is believed that guinea pig chewing bursts provide a convenient laboratory based model for elucidating the neuro-physiologic mechanisms of this time constant.
Sequential Assessment and Decision-Making in Humans
Authors: Sullivan Matthew S. , Burnham Dawn , Stevens-Wood Barry , Sheldon Ben C.
Published: April 2008

In two experiments inspired by theories of sequential information-gathering tasks such as sequential mate assessment, human subjects were asked to view sequences of pictures of mythical birds, each of which varied in value according to one of three stimuli, namely tail length, band width or intensity of black and carried an associated score. The subjects chose one picture from the sequence so as to maximise their points scored. Only one picture could be seen at a time, if a picture was rejected it could not be revisited and there was a small constant devaluation of each successive picture. In the first experiment two random sequences of each of the three stimuli were viewed and subjects were given no prior information on the population of pictures, nor was the devaluation specified. In the second experiment, which used only pictures which varied in tail length, subjects cach saw a different random sequence and then the same fixed sequence. In addition, they were told there was either a 5%, 10% or 20% devaluation of succesive birds, and half the subjects were given prior information on the population to be viewed. Thus in this experiment scores could be corrected for position in the sequence. To summarise the major results: 1. Choice was made at an early stage in the sequence, usually the 3rd, 4th or 5th picture, and this was consistent in both experiments. 2. In Experiment 2, subjects given prior information or smaller devaluation functions chose later in the sequence. 3. In Experiment 2 there were no differences in the corrected scores achieved by subjects in our treatments of prior information or devaluation, but subjects achieved higher absolute scores as the devaluation decreased. 4. In both experiments the value of the chosen picture was positively correlated with the mean value of the prior sequence seen when absolute scores are used, but in Experiment 2 this effect disappears when corrected scores are used. 5. A large positive jump was a cue to stop in both the random and fixed sequences. Identification of relevant variables and patterns of decision making may further enlarge our understanding of sequential assessment in humans and other animal species.
Mirror Image Pattern Matching By Bumble Bees
Authors: Korneluk Y.G. , Plowright C.M.S.
Published: April 2008

Bumble bees (Bombus impatiens) were trained to discriminate between a rewarding and non-rewarding artificial flower that differed only in their configuration of four identical petals. On choice tests between 2 empty flowers, the bees chose the flower with the configuration of the rewarding flower over the mirror image, but the mirror image over a novel flower. This behaviour is the same as has been observed with honey bees and functional interpretations are considered. The problem of distinguishing between left-right pattern reversals and true mirror image transformations is discussed.
Experiments On Embryo Survivorship, Habitat Selection, and Competitive Ability of a Stickleback Fish (Gasterosteus) Which Nests in the Rocky Intertidal Zone
Authors: Macdonald J.F. , Macisaac S.M. , Bekkers J. , Blouw D.M.
Published: April 2008

Like other 'white' sticklebacks, those ncsting intertidally at Spry Bay, Nova Scotia, Canada, remove fertilized eggs from the nest, disperse them over the surrounding area, and provide no subsequent parental care. However the breeding substrate at Spry Bay is devoid of the filamentous algae which are the normal breeding substrate of the white stickleback and which elsewhere facilitate survival of abandoned embryos. Experiments show that embryos dispersed in the intertidal zone at Spry Bay survive surprisingly well despite the complete absence of parental care and the periodic absence of water. Intertidal embryos generally develop faster than embryos in the adjacent subtidal zone, but there are exceptions to this pattern. Intertidal males show site fidelity to their nests despite interrupted access to territory, and they show consistent preference for nesting in the intertidal zone in the field. In the laboratory, and in the absence of tidal flux and competition, males taken from the rocky intertidal zone generally prefer to breed on bare rock substrate even when filamentous algae are freely available. When white stickleback males from an adjacent population which breeds subtidally in filamentous algae are introduced into the experimental aquaria as competitors, they exclude the males that breed on bare rock. The surprisingly high survivorship of embryos in the rocky intertidal zone, the habitat selection of males for bare substrate, and their exclusion by males that breed subtidally on algae, all suggest that the highly unusual breeding behaviours of intertidal white males form an effective alternative breeding repertoire. Because breeding habitat selection has implications for mate selection, the possibility exists that sticklebacks with different breeding repertoires at Spry Bay may mate assortatively.
Individual Differences in Vocalisations of Young Barbary Macaques (Macaca Sylvanus): a Multi-Parametric Analysis To Identify Critical Cues in Acoustic Signalling
Authors: Hammerschmidt Kurt , Todt Dietmar
Published: April 2008

It had been shown that Barbary macaque (Macaca sylvanus) mothers are able to individually recognise their offspring by its vocal signals, but it remained unclear which acoustical cues may account for such an ability. In order to address this issue from a basic perspective, about 1800 calls of infants and yearlings (N = 10) were investigated. The investigation applied a method of signal analysis which allowed to determine a large number of parameters (N = 84) for each vocal signal. The application of discriminant and cluster analyses provided the following results: (1) Animals differed in almost all call parameters. However, individuals were best identified by specific parameters which formed an individually characteristic parameter set. (2) Those parameters that facilitated the assignment of vocal patterns to a given individual usually were different among individuals. (3) Infants and yearlings achieved the same maximum value of correct assignment. However, infants achieved a reasonable assignment at a much smaller number of call parameters. (4) Cluster analysis of vocalisations revealed that Barbary macaques uttered individual versions of common call types. (5) When the discriminant analysis was rerun on the call clusters, the correct assignment could be improved from 81 % to 94% for infants and from 80.5% to 96% for yearlings. Our findings suggest that Barbary macaque mothers can recognise their offspring by more than one signal cue, and such a strategy may improve the recognition system's robustness against possible distortions caused by the environment. The pronounced differences in vocal patterns of young Barbary macaques may help mothers or other group members to readily learn and recognise the individually specific signal features. The methodological procedures described in this paper provide a powerful tool for an assessment of signal parameters also in other areas of vocal interactions.
Individual Differences in Egg Cannibalism in Female Dark Chub (Pisces: Cyprinidae)
Authors: Katano Osamu , Maekawa Koji
Published: April 2008

Nine of 41 identifiable females of dark chub, Zacco temmincki, in a river cannibalized eggs of other females. There was no significant difference in body size, condition factor or the location of home range between cannibals and noncannibals. In laboratory experiments, one male and two females were introduced into an aquarium to observe the behaviour of individual females while a pair spawned. The response of 16 females to spawning was observed and 15 of 16 females exhibited egg cannibalism. The percentages of egg-eating behaviour for individual females varied from 11.1 to 81.8%, and did not change significantly over the course of the experiment. Dark chub were multiple spawners. In a river the number of spawning sequences for cannibals was significantly higher than that for noncannibals. The number of eggs laid by cannibals was estimated to be 1.55 times as many as that by noncannibals.
Memory for Locations of Stored Food in Willow Tits and Marsh Tits
Authors: Healy Susan D. , Suhonen Jukka
Published: April 2008

Some food-storing animals use spatial memory in food retrieval. There is variation amongst food-storing species in the duration over which food is stored and it is positively correlated with differences in the size of the part of the brain that is involved with memory for storage locations, the hippocampus. For example, British marsh tits (Parus palustris) are generally thought to retrieve their stores after a few hours or days whereas Scandinavian willow tits (P. montanus) have been shown to store their food for several weeks to months. Marsh tits also have a smaller hippocampus than do willow tits. This experiment tested the hypothesis that retrieval success (and thus memory capacity) of the two species differs depending on the usual length of time for which food is stored. Individuals of both species were tested on their ability to retrieve five stored food items after two differing delays: 2-3 h ('short') and 17 days ('long'). The prediction was that there would be no differences in retrieval performance between the species after the short delay but that willow tits would be more accurate at retrieving their stores than marsh tits after the long delay. The results did not provide support for this hypothesis as there were no differences between the species in retrieval performance following either delay: both species successfully retrieved food after both delays.
Genetic Influences On Coping Behaviour in House Mouse Lines Selected for Aggression: Effects of the y cHromosome
Authors: Sluyter Frans , Van Oortmerssen Geert A. , Koolhaas Jaap M.
Published: April 2008

Male wild house mice selected for Short Attack Latency (SAL) show an active coping style to environmental challenges, whereas males selected for Long Attack Latency (LAL) generally exhibit a passive coping style. Previous studies showed that the aggressive SAL males develop routines more quickly and show more resistance to environmental changes than the less aggressive LAL ones; the latter behave more flexibly in non-social situations. Furthermore, using reciprocal F1s and backcross lines for SAL and LAL males, a Y chromosomal effect on aggression has been demonstrated. The aim of this study was to examine possible effects of the Y chromosome on behavioural flexibility. For this purpose six genotypes (SAL, LAL, their reciprocal F1s and their congenics for the non-pseudoautosomal part of the Y chromosome) were tested for their behavioural flexibility in a Y-maze. Differences between SAL and LAL were reproduced. Congenic lines showed identical scores to their parental ones. Regarding the reciprocal F1s, differences in aggression were not associated with behavioural flexibility. Therefore, it may be concluded that the Y chromosome does not influence aggression-related behavioural flexibility.
The Foraging Behaviour of Mongolian Gerbils: a Behavioural Need or a Need To Know?
Authors: Forkman Björn
Published: April 2008

In the present paper Mongolian gerbils (Meriones unguiculatus) were shown to prefer to forage from an unprofitable food source when it contained hidden food, but not when the food was clearly visible. Four experiments were performed, in each experiment the animal could forage from either a food source with easily accessible food or from a food source which required more work. In the first experiment the animal could choose between seeds with husks and those without, and in the second experiment between seeds glued to a stick and seeds in a bowl. In both these experiments the animals could see the food of both food sources. The animals chose to forage from the most profitable food source, i.e. the seeds without husks and the seeds in a bowl respectively. In the third experiment the animals could choose between eating seeds hidden under lids or seeds in a bowl, and finally in the fourth experiment they could forage for seeds on a camouflaging surface or on a surface where the seeds were clearly visible. In these last two experiments it was impossible to see the food in the unprofitable food sources without working for it. In these situations the animals choose to forage from the unprofitable food source, i.e. from underneath the lids and on the camouflaging surface. These results are in accordance with exploration being the driving force behind contrafreeloading (learned industrioussness). The results cannot be explained by classical optimal foraging theory.
Environmental Stimuli Influence Oestrogen-Dependent Courtship Transitions and Brain Aromatase Activity in Male Ring Doves
Authors: Hutchison R.E. , Opromolla G. , Hutchison J.B.
Published: April 2008

In paired ring doves, Streptopelia risoria, male and female reproductive behaviour undergoes a series of synchronised transitions. The duration of each phase depends on the reproductive development of the pair. This study examines the effect of the environment in which behaviour is shown on both oestrogen-dependent courtship transitions and formation of oestrogen in the brain. The structuring of the cage environment had an immediate effect on transitions in male courtship behaviour. Males which were tested with females in a cage environment with a perch and a nest bowl (complex cage) displayed significantly less aggressive courtship and more nest-orientated behaviour than males tested with females in a cage environment without perch or nest bowl (simple cage). The response of males, which showed aggressive and nest-orientated courtship behaviour, to reproductively advanced females (abdominal length 1.4-1.6 cm) about to lay eggs or females in earlier stages of reproductive development (abdominal length 0.8-1.1 cm) did not differ initially. On the eighth day of 15-min daily tests, there was, however, an increase in aggressive courtship to females with smaller abdomens. This result suggests that male aggressiveness is more likely when the male and female reproductive cycles are not synchronised. We also tested whether environmental factors and the male's hormonal condition, which affect male courtship interactions, influence the formation of behaviourally effective oestrogen by aromatisation of testosterone in the brain. The aromatase activity was measured in the preoptic and anterior hypothalamic areas in relation to the time spent in interaction with females each day. Both intact and castrated males which interacted intermittently (15 min each day for 9 days) had higher preoptic aromatase activity than males which interacted continuously with females. The males which had high brain aromatase activity and had interacted intermittently with females were considered to represent the initial stages of the cycle. We conclude that cage environment and female reproductive condition influence the course of courtship interactions. Oestrogen formation in the male brain is affected by the type of interaction.
Is Group-Living Associated With Social Learning? a Comparative Test of a Gregarious and a Territorial Columbid
Authors: Lefebvre Louis , Palameta Boris , Hatch Karen K.
Published: April 2008

Group-living is often thought to be associated with social learning. Comparative tests are useful in evaluating the link between ecological variables and learning specializations, but controls are required to guard against possible confounding variables. In this paper, we test the association between group-living and social learning by comparing two opportunistic, urbanized, Columbids in a set of experiments involving shaping and individual learning controls. In part 1, we provide quantitative field data on foraging group size for the two species, the feral pigeon (Columba livia) studied in central Montréal and the Zenaida dove (Zenaida aurita) studied in coastal Barbados. The data confirm anecdotal reports that contrast the gregarious social organization of C. livia with the territorial organization of coastal Z. aurita. In part 2, we test pigeons and Zenaida doves on two food-finding tasks and show (1) that feral pigeons are better than Zenaida doves at solving all variants of the tasks presented, whether individually or socially learned, and (2) that once general species differences are taken into account, territorial Zenaida doves are not less efficient than gregarious feral pigeons at using food-finding information provided by a conspecific tutor. The results do not support the association between group-living and social learning and show that procedures like shaping and control variants of the task may help interpret interspecific differences in learning.
Mate Choice On Multiple Cues, Decision Rules and Sampling Strategies in Female Pied Flycatchers
Authors: Dale Svein , Slagsvold Tore
Published: April 2008

The mate sampling behaviour and mate choice of 125 individually marked female pied flycatchers, Ficedula hypoleuca, was recorded with video cameras. Females visited on average 3.1 males within a period of less than 1 day. Females had independent preferences for unmated males, brightly coloured males and males with nestboxes that had small entrance holes; 77-86% of the females chose a male that was the best one among the males sampled in relation to at least one of these factors. When having a choice only on mating status 91 % of the females made a correct choice; corresponding values for plumage colour and nest site quality were 64% and 73%, respectively. Females made 'mistakes' more often when differences between males were small, at least regarding plumage colour. When given simultaneous choices on two cues, females gave priority to the cue with the largest differences between males. Females returned to some males before rejecting them and these males tended to have brighter plumage or better nestboxes than males that were visited only once. The final choice of mate was not related to the order in the sequence of males visited, suggesting that many females used a pool-comparison strategy. However, about one third of the females visited only one male, and one third sampled males in a way conforming to threshold or sequential comparison strategies as well as a pool-comparison strategy. The temporal pattern of female visits suggested that they either sampled males at once and then settled, or that they visited one male repeatedly and made occasional visits to other males, often after a long period of residency. Twenty-eight females (22%) made visits to other males after they had settled

(i.e.

started nest building) with one male, and this resulted in mate switching in seven cases (6% of all females). These results show that females compare and choose mates on the basis of at least three different cues, and that most females are able to pick out the best or one of the best males among those sampled. However, females sample few males, probably because of competition between females for a mate, so that they must sometimes accept dull or mated males, or males with poor-quality nest sites. Limited choice reduces the strength of sexual selection even when female preferences are strong. This may help explain why plumage colour variation and polygyny exist in the pied flycatcher.
Female Aquatic Warblers (Acrocephalus Paludicola) Are Attracted By Playback of Longer and More Complicated Songs
Authors: Catchpole Clive K. , Leisler Bernd
Published: April 2008

Male aquatic warblers are relatively unusual in producing three different song structures, A, B and C. The shorter A-B songs have been shown to function in male-male aggressive interactions, and it was speculated that the longer and more complex C songs might function in female attraction. The present playback experiments were carried out on hormone-implanted females in a large, experimental aviary. When playback was of a male singing C songs, females were attracted faster and for longer periods than when the same male produced A-B songs. Females gave relatively few sexual displays, but gave more in response to playback of C songs than to A-B songs. Aquatic warblers have an unusually promiscuous mating system with high rates of extra-pair fertilisation and multiple paternity within broods. Sexual selection through intense sperm competition may have accentuated the evolution of structurally distinct songs for female attraction and aggressive interactions between rival males.
Mate Guarding in Male Sand Lizards (Lacerta Agilis)
Authors: Olsson Mats , Gullberg Annica , Tegelström Hakan
Published: April 2008

We investigated factors that may determine mate guarding tactics in male sand lizards. In a sample of lizards from a museum collection, larger males had larger testis, but in laboratory experiments and in a natural population larger males did not sire more offspring. Males with long inter-copulatory intervals were more successful in sperm competition than males with short inter-copulatory intervals. In the wild, the operational sex ratio (OSR, No of receptive females/No of sexually active males) declined throughout the mating season. Mean duration of mate guardings was unaffected by OSR, time to ovulation, female age and mass, and clutch size. Larger males guarded females longer and were more likely to mate guard a female of similar age. Larger males had more partners but there was no correlation between male size or guarding time and the proportion of young that males sired in clutches from females mated with several partners. Males with more partners were more successful at siring offspring in clutches from females that mated with more than one partner. We suggest that fitter males are better at both mate acquisition and have more competitive sperm.
Chaffinch (Fringilla Coelebs) Epaulette Display Depends On the Degree of Exposure But Not Symmetry of Intruder's Epaulettes
Authors: Jablonski P.G. , Matyjasiak P.
Published: April 2008

1. Epaulettes, white wing patches, are exposed in agonistisc displays between territorial chaffinch males. 2. As with many bilateral traits one should expect that asymmetrical development of the two wing patches could indicate poorer individual. Therefore it is likely that territory owners change their display toward asymmetrical competitor. 3. We tested the effect of exposure and symmetry of epaulettes of a stuffed bird on epaulette exposure of the territorial male. The results showed that: 4. males increased the degree of their epaulette exposure in response to larger epaulette on the mount; 5. males did not respond to the asymmetry of epaulettes on the mount. 6. The results aggree with the interpretation that the males' display of exposed epaulettes to each other could be regarded as communication. The epaulette display could be a signal of high aggressive motivation in the chaffinch.
Larval Prepupation Behaviour of Drosophila Pavani, Drosophila Gaucha and Their Reciprocal Hybrids
Authors: Godoy-Herrera Raúl , Silva José Luis
Published: April 2008

The behavioural mechanisms by which the larvae of the sibling species D. pavani and D. gaucha, and their reciprocal hybrids select pupation sites are described in terms of larval substrate preferences. If the larval behaviour of the parental species and their reciprocal hybrids during pupation leads them to pupate in different substrates, such preferences could be used to identify environmental factors and genetic mechanisms involved in the evolution of that behaviour. Confronted with dry substrates, interspecific hybrid larvae pupated in the rearing cup, while the parental species pupated both outside and inside the cup. Like the parental species, the hybrids pupated outside, when humid substrates surrounded the rearing cup. Larvae from D. pavani and D. gaucha showed a broader norm of reaction than the hybrids. D. pavani larvae occupied dry and humid substrates to pupate, while D. gaucha larvae tended to prefer only humid substrates. Larvae of D. pavani burrowed into dry sand pupated preferently in the deep layers of the substrate. Few D. gaucha larvae burrowed; they tended to pupate in the upper layers of dry sand. D. pavani larvae pupated on the moist sand, while most of D. gaucha larvae burrowed and formed puparia in the upper layers of the substrate. The hybrid larvae showed no burrowing behaviour in either dry or moist sand.
The Importance of Different Paternity Guards in the Polygynandrous Penduline Tit (Remiz Pendulinus)
Authors: Schleicher B. , Ho H. , Valera F. , Hoi-Leitner M.
Published: April 2008

It is well documented that extra-pair copulations are a strategy by which males can increase their reproductive success and females may obtain genetic benefits. Whereas in monogamous species extra-pair copulations are the only way for both sexes to increase their reproductive success, in polygamous systems both partners can benefit from mating with several individuals. Here we examine the intensity of sperm competition and the rate of extra-pair fertilizations in relation to male anti-cuckoldry tactics in a small passerine, the polygynandrous penduline tit (Remiz pendulinus), where both sexes have the opportunity to become polygamous. The results revealed rather low rates of extra-pair paternity for this species: 6.9% (14 out of 201) of young being sired by an extra-pair male. Males build elaborate nests to attract females and because of this high initial investment, one would expect males to evolve anti-cuckoldry tactics to ensure paternity. However, male mate guarding intensity as well as within-pair copulation frequency were rather low in comparison to other polygynandrous species, and hence both strategies are unlikely to ensure paternity. In fact our results show that those males which deserted their females early in their fertile cycle (already before the second egg is laid) did not lose paternity, whereas those males which tended to guard their females throughout their whole fertile period were more likely to be cuckolded. Thus, although no obvious anti-cuckoldry tactics exist in this species, extra-pair paternity is very low. This indicates a tendency in females to cooperate with their pair-males rather than seek extra-pair copulations.
Distribution of Parental Investment and Sibling Competition in the Herring Gull, Larus Argentatus
Authors: Davis Jennifer , Quinn James S.
Published: April 2008

Herring gulls, Larus argentatus, typically lay three eggs. The third laid egg is smaller, hatches later, and hatches a lighter, smaller chick than the first two. The third hatched chick also has a lower chance of survival. Observations of parent-chick and chick-chick interactions were conducted at two Ontario sites in the Great Lakes to determine whether and how parents might behaviorally bias investment in their chicks after the incubation period, and how interactions among chicks might add to the third chick disadvantage. Little evidence was found for behavioral discrimination against the third chick by either its parents or its siblings. The last hatched (C) chick was not less likely than its older siblings (A or B) to get to the food first, and while A and B were more likely to target C when initiating tugs-of-war over food, they were not more likely than C to initiate tugs-of-war in general. C pecked siblings the most, and, despite its younger age and smaller size, was not more likely to lose tugs-of-war with its siblings. It is likely that the locations where this study was conducted represent relatively benign environment in which to raise chicks compared to the marine populations observed in other studies. Given this, parents might be expected to reduce chick asymmetries if they are able. There was a high degree of hatching synchrony in Hamilton Harbor. In 7 out of 28 nests the C chick hatched on the same day as the B or A and B chicks.
Incomplete Female Knowledge of Male Quality May Explain Variation in Extra-Pair Paternity in Birds
Authors: Slagsvold Tore , Lifjeld Jan T.
Published: April 2008

We present and discuss an hypothesis to explain inter- and intraspecific variation in levels of extra-pair paternity (EPP) in birds. In species with biparental care, females may be willing to engage in extra-pair copulation (EPC) to improve the genetic quality of the offspring. However, it may be costly to sample males and difficult to assess their genetic quality. Hence, we suggest that variation occurs in the extent of such knowledge between females, causing variation in the extent to which they are willing to engage in EPC. From the hypothesis we present nine predictions on occurrence of EPP in birds, e.g. cuckolders should mainly be resident, close neighbours; rate of EPP should be positively related to breeding density, to rate of male intrusion, to female opportunity to assess male quality from competitive interactions between males, to early arrival time of females relative to time of egg laying, and to breeding synchrony. Finally, we discuss implications on male behaviour. We suggest a new function of male mate guarding, namely that mate guarding is a means to prevent the social mate from obtaining essential information about the quality of potential extra-pair mates.
The Freshwater Calanoida (Copepoda) of the Philippines
Authors: Lai H.C. , Mamaril A. , Fernando C.H.
Published: April 2008

Cinq espèces de copépodes calanoides de l'eau douce des Philippines, avec leurs distributions et leur taxonomies, sont décrites. Deux espèces d'entre eux, Tropodiaptomus gigantoviger et Filipinodiaptomus insulanus n. g., sont endèmes pour les îles des Philippines. T. vicinus est abondant dans les provinces du sud. Monglodiaptomus birulai est présent seulement dans les endroits isolés à côté de la Ville Baguio. Une clé taxonomique pour les copépodes calanoides de l'eau douce des îles des Philippines est formulé.
Cirolanidae (Isopoda) From French Polynesian Coral Reefs: Description of Three New Species
Authors: Muller H.-G. , Salvat B.
Published: April 2008

This first contribution on cirolanid isopods from shallow water coral reef locations in French Polynesia (Bora Bora, Moorea) reports on three new species of the genera Cirolana and Metacirolana. They are described in detail, with remarks on their intergeneric affinities, habitat preference and biogeography.
Larval Development of the Hermit Crab Diogenes Miles (Herbst, 1791) (Decapoda, Anomura, Diogenidae) in the Laboratory
Authors: Shenoy Shakuntala , Sankolli K.N.
Published: April 2008

Hermit crabs are the commonest intertidal anomuran crustaceans. Diogenes miles (Herbst) is an inhabitant of surf-beaten sandy shores along coasts of peninsular India. This species is outstanding among other diogenid hermit crabs in having, unlike others, an extremely flat and broad body well adapted for its occurrence in long, narrow-mouthed gastropod shells mostly of Oliva and to lesser extent Gypraea and Conus. During the present study it was observed that, contrary to what was expected, D. miles docs not breed throughout the year but appears to have its breeding season restricted to the summer months. This was indicated by the collection of ovigerous females of the species only during the summer months near Bombay, Ratnagiri and Karwar along the Indian west coast. Eggs are minute, bright crimson to scarlet when immature and are easily shed, even with slight disturbance. Larval development consists of 3 zoeal and a megalopa stages, described in the present paper, after specimens reared in the laboratory. Some of the salient features of the zoea larvae are: a long, pointed rostrum, smooth carapace, usual triangular telson with process formula 7 + 7 in the first zoea but complete reduction of the 4th process in the third zoea. The megalopa has the typical unequal chelipeds, the left being larger, only 3 pairs of pleopods, and the telson is rectangularly rounded. Though the deep curve of the carpus develops right from the megalopa stage, the inward right-angled bend of the cheliped, so characteristic of the adult, is not fully developed even in the 5 subsequent instars.
A Field Key To the Seed of Penaeid Prawns Along the Konkan Coast (West Coast of India)
Authors: Chaudhari K.J. , Jalihal D.R.
Published: April 2008

Despite the advancement in prawn culture technology in several parts of the world, India will be still depending on wild seed for prawn farming for some more time. In this context, selective stocking is very important. Yet, practically no information is available on the correct identification of juvenile or seed stage (size: 6 to 60 mm) although a lot of work is done on larval and postlarval stages. Various morphological changes, including colouration, take place during juvenile phase rendering the segregation of seed of different species even more difficult. The present work, based on seed collection from the wild and supplemented by laboratory observations over a period of two years, gives a detailed field key for the following 11 species belonging to 4 genera occurring along the Konkan coast (west coast of India): (1) Penaeus (Penaeus) monodon, (2) P. (P.) semisulcatus, (3) Penaeus (Fenneropenaeus) merguiensis, (4) P. (F.) indicus, (5) Penaeus (Marsupenaeus) japonicus, (6) Metapenaeus dobsoni, (7) M. monoceros, (8) M. affinis, (9) M. moyebi, (10) Parapenaeopsis cornuta, (11) Metapenaeopsis sp. The key is based on colour in live condition, habitat and salinity preference, swimming and burying behaviour, morphological, meristic and morphometric studies.
Freshwater Crabs as Poor Zoogeographical Indicators: a Critique of Banarescu (1990)
Authors: Ng Peter K.L. , Rodriguez Gilberto
Published: April 2008

A critique of Bănărescu's (1990) ideas and hypotheses regarding the importance of freshwater crabs in zoogeography is presented. We contend that many of Bănărescu's generalizations are too simplistic and do not agree with our observations and findings about freshwater crabs. The value of freshwater crabs in zoogeography is briefly discussed.
On a Tropical Subspecies of Monstrilli Wandelii (Copepoda, Monstrilloida) From the Mexican Coasts of the Caribbean Sea
Authors: Suárez-Morales E.
Published: April 2008

From plankton samples taken at a reef lagoon off Puerto Morelos, on the northern portion of the eastern coast of the Yucatan Peninsula, a new tropical subspecies of Monstrilla wandelii, only known from temperate-cold latitudes, is described from male specimens. The analysis of the main characteristics in the taxonomy of monstrilloids allowed its identification as M. wandelii. The new subspecies differs from the nominal species in the relative length and armature of the antennular segments, in the structure of the genital lappets of the fifth legs and in its total size, which is nearly 2.5 times that of the nominal subspecies.
A New Species of Cerceis (Isopoda, Sphaeromatidae) From the Arabian Sea
Authors: Javed Waquar , Yousuf Farzana
Published: April 2008

Cerceis biforamina sp. nov. belonging to the Dynameninae, collected from algae of the intertidal pools of Bulleji, Karachi, is described and figured. The genus Cerceis Milne-Edwards is for the first time recorded from the Arabian Sea. The relationship of Cerceis biforamina sp. nov. with Cerceis bicarinata Barnard, 1936 is also discussed.
Burrowing Behaviour and Cost in the Sandy-Beach Oniscid Isopod Tylos Granulatus Krauss, 1843
Authors: Brown A.C. , Trueman E.R.
Published: April 2008

Tylos granulatus is an isopod living above the driftline on sandy shores, burrowing to depths of up to a metre or more. Burrowing has been investigated by analyzing video recordings and traces from isotonic and isometric transducers. In crawling, all seven pairs of pereiopods operate in a similar manner and display metachronal rhythm, while in burrowing pereiopods 1 to 3 do the digging, pairs 4 to 6 compact the excavated sand, and pair 7 pushes the bolus behind the animal. Movements of the head also play a significant role in burrowing. Clockwise or anticlockwise partial rotation occurs during burrowing, which takes place in a stepwise progression. With a Burrowing Rate Index of 3, the animal must be considered a powerful burrower, while the energy cost of burrowing is surprisingly low at some 0.3 J m-1.
The Copepodid of Peniculisa Shiinoi Izawa, 1965 (Copepoda, Siphonostomatoida, Pennellidae), a Single Free-Swimming Larval Stage of the Species
Authors: Izawa Kunihiko
Published: April 2008

The copepodid stage of the parasitic copepod Peniculisa shiinoi Izawa, 1965 (Siphonostomatoida, Pennellidae), parasitic on the fins of a puffer fish, Canthigaster rivulatus, is described based on specimens reared from eggs. This is the only free-swimming larval stage of P. shiinoi. The copepodid is distinctly smaller than those of the known pennellids. However, the dispensability of the free-swimming nauplius stage is independent of the egg-size. The copepodid antennae of the pennellids are certainly uniramous. The setation of the rami of the copepodid legs varies among pennellids.
First Records of the Genus Ceratonotus G. O. Sars, 1909 (Copepoda, Ancorabolidae) From the Southern Hemisphere, With the Description of Two New Species
Authors: Schminke Horst Kurt , George Kai Horst
Published: April 2008

Two new ancorabolid species, Ceratonotus magellanicus sp. n. and Ceratonotus antarcticus sp. n., are described from the Straits of Magellan (Chile) and from Halley Bay (Weddell Sea, Antarctica), respectively. This is the first record of the genus from the Southern Hemisphere extending its range to the extreme south of the globe. Both new species are clearly distinct, each characterized by several unique features. They share a few characters which are absent in the two known species from the Northern Hemisphere. It is, however, not clear yet whether this indicates that they represent a subgroup distinct from the northern species within the genus.
Metaphors and Metaphoric Objects
Authors: Jooste E.T. , Cleaver Glenda
Published: April 2008

This article reports on an exploratory study that used metaphoric objects as a therapeutic aid. During Rogerian therapy sessions, a metaphoric object was handed to clients. The metaphoric object was used as a reflection of an aspect of the client's being. The clients were asked to describe the effect the object had on them. The protocols obtained were subjected to a phenomenological analysis. The study indicates that metaphoric objects can be a useful therapeutic aid.
The Role of "Recognition" in the Resolution of a Specific Interpersonal Dilemma
Authors: Løvlie Schibbye Anne-Lise
Published: April 2008

In this article the author argues that recognition of self or others is necessary for structural changes in our clients as well as for growth in all relationships. Recognition is seen as a way to deal with our conflicting needs as we progress toward an individuated self and as a way to solve conflicts within our relationships. From a dialectical perspective, dysfunctional interaction between partners reveals both the conflict and the lack of recognition. Various ways of resolving the dilemma are explored. An analysis of a mother-child interaction shows that intersubjectivity is basic in recognition. The dialectic perspective emphasizes in addition the threat and mutuality involved in recognition. With mutual recognition we gain ourselves both as subjects and as objects, and we preserve the relationship. Finally, implications of the dialectical way of conceptualizing relationships are summarily presented.
Archaeological Studies in Turkmenistan
Authors: Gaibov V.A. , Koshelenko G.A. , Bader A.N.
Published: April 2008

The study of ancient sites in Turkmenistan has in the 80s focused on the oasis of Merv (ancient Margiana), the Uzboy valley and Old Nisa. At Merv a joint Central Asian-Italian team has been preparing an archaeological map of the oasis, based on information from a complete survey of the area (over 220 sites), fixed-site excavations and sondage digs. The survey shows the continuity of different monuments on the same sites, the shift of the centre of the oasis from north to south by the time of the building of Antiochia Margiana in the 3rd c. B.C. and the reoccupation of the north by fortified settlements following the full settlement, irrigation and cultivation of the south after the 1st c. B.C. Excavations were made of fortified settlements at Chilbourj and Göbekli-depe (where over 2000 Parthian clay bullae were found). Study of sites along the Uzboy valley has altered views about changes in aridity/humidity in the area. A new period of humidity in the 7th c. B.C.-4th c. A.D. has been associated with the activity of a group of nomadic cattlebreeders, identified with the Massagetae, whose tribal centre is thought to have been the unusual site at Ichjanli-depe. At the important Parthian centre of Old Nisa recent study has been made of the "building with a square hall" (which may have been a fire temple), the "tower" of Old Nisa (whose architecture is unique in the Hellenistic Orient) and the "round temple", while near to the city investigations of the important Parthian complex at Mansurdepc have revealed two remarkable pottery fragments with painted portraits.
A Head of Mithras From the Tauric Chersonesus
Authors: Saprykin S. Yu.
Published: April 2008

In 1986 the chance find was made at Chersonesus of a head of Mithras, dated to the 2nd/3rd quarter of the 2nd c. A.D. and of provincial Roman origin. Close parallels to the piece suggest its provenance in a Mithraeum which provides new evidence for the spread of the cult in the N. Black Sea region. This is commonly associated with the stay there of Roman troops from Lower Moesia and Thrace. Similarities with heads of Mithras from Escus in Lower Moesia point to the possibility that the Chersonesus head was left by Legio V Macedonica.
The Odessa Museum of Archaeology
Authors: Okhotnikov S.B.
Published: April 2008

The Odessa Museum of Archaeology was founded in 1825 by local antiquarians. The museum's collection grew in part due to excavations of classical sites in the region, in part due to gifts and purchases from dealers in classical antiquities. Up to the Second World War the focus of the Museum's activities was classical archaeology. In the post-war period this expanded to include the whole of the ancient history of the region from the Stone Age to the Middle Ages. The museum now houses one of the best collections of Classical Antiquities in the former Soviet Union and the third-ranking Egyptological collection. The museum formed from 1972 part of the Soviet Academy system and undertook fieldwork on the Lower Dniester at Bronze Age sites, as well as at classical sites such as Tyras, Nikonion, the site of the ancient Odessos, and Leuke and medieval sites such as Belgorod.