Zoology
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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 5.
Steller sea lions Eumetopias jubatus and nutritional stress: evidence from captive studies
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Numbers of Steller sea lions Eumetopias jubatus in the North Pacific have declined. According to the nutritional stress hypothesis, this decline is due to reduced food availability. Data from studies conducted on pinnipeds in the laboratory are used here to test if the nutritional stress hypothesis can explain the decline of Steller sea lions. Overall, there is strong evidence for biologically meaningful differences in the nutritional quality of major prey species. Steller sea lions can partly compensate for low-quality prey by increasing their food consumption. There appear to be no detrimental effects of low-lipid prey o...
Source: Mammal Review - September 28, 2009 Category: Zoology Authors: DAVID A. S. ROSEN Tags: Reviews Source Type: journals
Evidence for duplicated Hox genes in polyploid Cyprinidae fish of common carp, crucian carp and silver crucian carp.Email this article to a colleague.
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Recent studies on comparative genomics have suggested that a round of fish-specific whole genome duplication (3R) in ray-finned fishes might have occurred around 226-316 Mya. An additional genome duplication, specifically in cyprinids, may have occurred more recently after the divergence of the teleosts. The timing of this event, however, is unknown. To address this question, we sequenced four Hox genes from taxa representing the polyploid Cyprinidae fish, common carp (Cyprinus carpio, 2n=100), crucian carp (Carassius auratus auratus, 2n=100) and silver crucian carp (Carassius auratus gibelio, 2n=156), and compared the...
Source: Journal of Experimental Zoology. Part B. Molecular and Developmental Evolution - September 28, 2009 Category: Zoology Authors: Yuan J, He Z, Yuan X, Jiang X, Sun X, Zou S Tags: J Exp Zoolog B Mol Dev Evol Source Type: journals
Paul Kammerer's midwife toads: about the reliability of experiments and our ability to make sense of them.Email this article to a colleague.
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PMID: 19790195 [PubMed - as supplied by publisher]
Source: Journal of Experimental Zoology. Part B. Molecular and Developmental Evolution - September 28, 2009 Category: Zoology Authors: Wagner GP Tags: J Exp Zoolog B Mol Dev Evol Source Type: journals
Carbon Turnover in Tissues of a Passerine Bird: Allometry, Isotopic Clocks, and Phenotypic Flexibility in Organ SizeEmail this article to a colleague.
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Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract Stable isotopes are an important tool for physiological and behavioral ecologists, although their usefulness depends on a thorough understanding of the dynamics of isotope incorporation into tissue(s) over time. In contrast to hair, claws, and feathers, most animal tissues continuously incorporate carbon (and other elements), and so carbon isotope values may change over time, depending on resource use and tissue‐specific metabolic rates. Here we report the carbon turnover rate for 12 tissues from a passerine bird, the zebr...
Source: Physiological and Biochemical Zoology - September 28, 2009 Category: Zoology Tags: article Source Type: journals
Two matched filters and the evolution of mating signals in four species of cricket.Email this article to a colleague.
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Conclusions:
Our results show that a mismatch between the sensitivity and directionality tuning is not uncommon in crickets, and an observed match (T. commodus) appears to be the exception rather than the rule. The data suggests that independent variation of both filters is possible. During evolution each sensory task may have been driven by independent constraints, and may have evolved towards its own respective optimum.
Source: Frontiers in Zoology - September 27, 2009 Category: Zoology Authors: Konstantinos KostarakosMatthias HennigHeiner Romer Source Type: journals
Sperm traits in Chinook salmon depend upon activation medium: implications for studies of sperm competition in fishesEmail this article to a colleague.
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P. Rosengrave, R. Montgomerie, V. J. Metcalf, K. McBride, and N. J. Gemmell - Sperm traits of externally fertilizing fish species are typically measured in fresh (or salt) water, even though the spawning environment of their ova contains ovarian...
Source: Canadian Journal of Zoology - September 26, 2009 Category: Zoology Source Type: journals
Dogs Canis familiaris as carnivores: their role and function in intraguild competitionEmail this article to a colleague.
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Dogs Canis familiaris are the world's most common carnivore and are known to interact with wildlife as predators, prey, competitors, and disease reservoirs or vectors. Despite these varied roles in the community, the interaction of dogs with sympatric wild carnivore species is poorly understood. We review how dogs have been classified in the literature, and illustrate how the location and ranging behaviour of dogs are important factors in predicting their interactions with wild prey and carnivores. We detail evidence of dogs as intraguild competitors with sympatric carnivores in the context of exploitative, interference an...
Source: Mammal Review - September 25, 2009 Category: Zoology Authors: ABI TAMIM VANAK, MATTHEW E. GOMPPER Source Type: journals
Failure to estimate reliable sex ratios of guanaco from road-survey dataEmail this article to a colleague.
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Julieta Pedrana, Alejandro Rodríguez, Javier Bustamante, Alejandro Travaini, and Juan I. Zanón Martínez - The guanaco (Lama guanicoe (Müller, 1776)) is a monomorphic polygynous mammal whose adult sex ratio is expected to be balanced or biased towards females. Remarkably...
Source: Canadian Journal of Zoology - September 25, 2009 Category: Zoology Source Type: journals
Abundance, social organization, and population trend of the arctic wolf in north and east Greenland during 1978 - 1998Email this article to a colleague.
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Ulf Marquard-Petersen - Abundance, social organization, and population trend of the arctic wolf (Canis lupus arctos Pocock, 1935) in north and east Greenland, 1978 - 1998, were determined from 353...
Source: Canadian Journal of Zoology - September 25, 2009 Category: Zoology Source Type: journals
Age-specific growth, survival, and population dynamics of female Australian fur sealsEmail this article to a colleague.
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J. Gibbens and J.P.Y. Arnould - Postsealing population recovery rates of fur seals and sea lions have differed markedly, perhaps owing to habitat type. Australian fur seals (Arctocephalus pusillus doriferus Wood...
Source: Canadian Journal of Zoology - September 25, 2009 Category: Zoology Source Type: journals
Islet tameness: escape behavior and refuge use in populations of the Balearic lizard (Podarcis lilfordi) exposed to differing predation pressureEmail this article to a colleague.
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William E. Cooper, Jr., Dror Hawlena, and Valentín Pérez-Mellado - Prey often exhibit reduced escape behavior on islands where predators are absent or scarce. Models of escape and refuge use predict that prey from populations...
Source: Canadian Journal of Zoology - September 25, 2009 Category: Zoology Source Type: journals
Mechanisms Influencing the Timing and Success of Reproductive Migration in a Capital Breeding Semelparous Fish Species, the Sockeye SalmonEmail this article to a colleague.
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Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract Two populations of homing sockeye salmon (Oncorhynchus nerka; Adams and Chilko) were intercepted in the marine approaches around the northern and southern ends of Vancouver Island (British Columbia, Canada) en route to a natal river. More than 500 salmon were nonlethally biopsied for blood plasma, gill filament tips, and gross somatic energy (GSE) and were released with either acoustic or radio transmitters. At the time of capture, GSE, body length, and circulating testosterone ([T]) differed between populations, differences...
Source: Physiological and Biochemical Zoology - September 25, 2009 Category: Zoology Tags: article Source Type: journals
Maternal Effects Increase Within‐Family Variation in Offspring SurvivalEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Maternal effects are environmental components of phenotypes that complicate relationships between natural selection and evolution because they often affect phenotypes and fitness simultaneously. We studied the effects of egg size variation on juvenile survival in a population of American coots (Fulica americana). We experimentally evaluated egg size variation at three levels: across the population, within natal nests, and within foster nests. Natal nests accounted for the most variation in population egg size. Within clutches, early‐la...
Source: The American Naturalist - September 25, 2009 Category: Zoology Tags: article Source Type: journals
Cell biology of adhesive setae in gecko lizards.Email this article to a colleague.
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Adhesive devices of digital pads of gecko lizards are formed by microscopic hair-like structures termed setae that derive from the interaction between the oberhautchen and the clear layer of the epidermis. The two layers form the shedding complex and permit skin shedding in lizards. Setae consist of a resistant but flexible corneous material largely made of keratin-associated beta-proteins (KAbetaPs, formerly called beta-keratins) of 8-22kDa and of alpha-keratins of 45-60kDa. In Gekko gecko, 19 sauropsid keratin-associated beta-proteins (sKAbetaPs) and at least two larger alpha-keratins are expressed in the setae. Some...
Source: Zoology - September 24, 2009 Category: Zoology Authors: Alibardi L Tags: Zoology (Jena) Source Type: journals
Cost of Reproduction, Resource Quality, and Terminal Investment in a Burying BeetleEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: We evaluate the cost‐of‐reproduction hypothesis in the burying beetle Nicrophorus orbicollis and examine how the importance of this trade‐off changes as females age (i.e., the terminal‐investment hypothesis). These beetles breed on small vertebrate carcasses, which serve as a food resource for them and their offspring. Consistent with the cost‐of‐reproduction hypothesis, females manipulated to overproduce offspring suffered a reduction in fecundity and life span when compared to controls, although all reproducing females had ...
Source: The American Naturalist - September 24, 2009 Category: Zoology Tags: article Source Type: journals
Facilitation of learning spatial relations among locations by visual cues: generality across spatial configurations.Email this article to a colleague.
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Spatial pattern learning permits the learning of the location of objects in space relative to each other without reference to discrete visual landmarks or environmental geometry. In the present experiment, we investigated conditions that facilitate spatial pattern learning. Specifically, human participants searched in a real environment or interactive 3-D computer-generated virtual environment open-field search task for four hidden goal locations arranged in a diamond configuration located in a 5 x 5 matrix of raised bins. Participants were randomly assigned to one of three groups: Pattern Only, Landmark + Pattern, or ...
Source: Animal Cognition - September 23, 2009 Category: Zoology Authors: Sturz BR, Kelly DM, Brown MF Tags: Anim Cogn Source Type: journals
How do African grey parrots (Psittacus erithacus) perform on a delay of gratification task?Email this article to a colleague.
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Humans and other animals often find it difficult to choose a delayed reward over an immediate one, even when the delay leads to increased pay-offs. Using a visible incremental reward procedure, we tested the ability of three grey parrots to maintain delay of gratification for an increasingly valuable food pay-off. Up to five sunflower seeds were placed within the parrot's reach, one at a time, at a rate of one seed per second. When the parrot took a seed the trial was ended and the birds consumed the accumulated seeds. Parrots were first tested in daily sessions of ten trials and then with single daily trials. For mult...
Source: Animal Cognition - September 23, 2009 Category: Zoology Authors: Vick SJ, Bovet D, Anderson JR Tags: Anim Cogn Source Type: journals
Generation of neural crest progenitors from human embryonic stem cells.Email this article to a colleague.
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The neural crest (NC) is a transient population of multipotent progenitors arising at the lateral edge of the neural plate in vertebrate embryos, which then migrate throughout the body to generate diverse array of tissues such as the peripheral nervous system, skin melanocytes, and craniofacial cartilage, bone and teeth. The transient nature of neural crest stem cells make extremely challenging to study the biology of these important cells. In humans induction and differentiation of embryonic NC occurs very early, within a few weeks of fertilization giving rise to technical and ethical issues surrounding isolation of e...
Source: Journal of Experimental Zoology. Part B. Molecular and Developmental Evolution - September 23, 2009 Category: Zoology Authors: Chimge NO, Bayarsaihan D Tags: J Exp Zoolog B Mol Dev Evol Source Type: journals
Mammalian Metabolic Allometry: Do Intraspecific Variation, Phylogeny, and Regression Models Matter?Email this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Power scaling relationships between body mass and organismal traits are fundamental to biology. Compilations of mammalian masses and basal metabolic rates date back over a century and are used both to support and to assail the universal quarter‐power scaling invoked by the metabolic theory of ecology. However, the slope of this interspecific allometry is typically estimated without accounting for intraspecific variation in body mass or phylogenetic constraints on metabolism. We returned to the original literature and culled nearly all ...
Source: The American Naturalist - September 23, 2009 Category: Zoology Tags: article Source Type: journals
The Good‐Genes and Compatible‐Genes Benefits of Mate ChoiceEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Genetic benefits from mate choice could be attained by choosing mates with high heritable quality (“good genes”) and that are genetically compatible (“compatible genes”). We clarify the conceptual and empirical framework for estimating genetic benefits of mate choice, stressing that benefits must be measured from offspring fitness because there are no unequivocal surrogates for genetic quality of individuals or for compatibility of parents. We detail the relationship between genetic benefits and additive and nonadditive genetic v...
Source: The American Naturalist - September 23, 2009 Category: Zoology Tags: article Notes and Comments Source Type: journals
The Schnauzenorgan-response of Gnathonemus petersiiEmail this article to a colleague.
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Conclusions:
Our experiments show a novel motor response that is mediated by the active electric sense of Gnathonemus petersii. This response will allow a detailed analysis of the neural system underlying direct interaction between sensory and motor processes in future experiments.
Source: Frontiers in Zoology - September 21, 2009 Category: Zoology Authors: Jacob EngelmannSabine NobelTimo RoverGerhard von der Emde Source Type: journals
Do anvil-using banded mongooses understand means-end relationships? A field experiment.Email this article to a colleague.
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Tool use and the associated need to choose appropriate objects for a particular task are thought to have selected for specialized cognitive abilities such as means-end comprehension. Several studies on large-brained tool-using primates and birds have demonstrated understanding of causal relationships to some extent. However, a comprehensive appraisal of this hypothesis requires testing for means-end comprehension also in non-tool-users as well as in small-brained tool users. Moreover, the results of captive studies do not answer the question whether such cognitive abilities are relevant to an animal in its natural envi...
Source: Animal Cognition - September 21, 2009 Category: Zoology Authors: Müller CA Tags: Anim Cogn Source Type: journals
Why Does Size Matter? A Test of the Benefits of Female Mate Choice in a Teleost Fish Based on Morphological and Physiological Indicators of Male QualityEmail this article to a colleague.
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Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract In female mate choice, a female chooses a reproductive partner based on direct or indirect benefits to the female. While sexual selection theory regarding female mate choice is well developed, there are few mechanistic studies of the process by which females evaluate reproductive partners. Using paternal‐care‐providing smallmouth bass (Micropterus dolomieu) as a model, the purpose of this study was to determine the relationship between female mate choice and the morphological and physiological status of chosen males. Thi...
Source: Physiological and Biochemical Zoology - September 21, 2009 Category: Zoology Tags: article Source Type: journals
Do rufous hummingbirds (Selasphorus rufus) use visual beacons?Email this article to a colleague.
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Animals are often assumed to use highly conspicuous features of a goal to head directly to that goal ('beaconing'). In the field it is generally assumed that flowers serve as beacons to guide pollinators. Artificial hummingbird feeders are coloured red to serve a similar function. However, anecdotal reports suggest that hummingbirds return to feeder locations in the absence of the feeder (and thus the beacon). Here we test these reports for the first time in the field, using the natural territories of hummingbirds and manipulating flowers on a scale that is ecologically relevant to the birds. We compared the prediction...
Source: Animal Cognition - September 19, 2009 Category: Zoology Authors: Hurly TA, Franz S, Healy SD Tags: Anim Cogn Source Type: journals
Signatures of High‐Altitude Adaptation in the Major Hemoglobin of Five Species of Andean Dabbling DucksEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Hypoxia is one of the most important factors affecting survival at high altitude, and the major hemoglobin protein is a likely target of selection. We compared population genetic structure in the αA and βA hemoglobin subunits (HBA2 and HBB) of five paired lowland and highland populations of Andean dabbling ducks to unlinked reference loci. In the hemoglobin genes, parallel amino acid replacements were overrepresented in highland lineages, and one to five derived substitutions occurred at external solvent‐accessible positions on the ...
Source: The American Naturalist - September 17, 2009 Category: Zoology Tags: article Source Type: journals
Maternal Effects Mediated by Antioxidants and the Evolution of Carotenoid‐Based Signals in BirdsEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Bright yellow to red signals used in mate choice or intrasexual competition are based on carotenoid pigments that are hypothesized to be traded between physiological functions and coloration. These signals have recently been shown to be influenced by maternal effects. Indeed, yolk‐derived carotenoids are essential for embryos to develop efficient carotenoid metabolism in posthatching life. Maternal effects facilitate adaptation to environmental variability and influence the evolution of phenotypic traits such as secondary sexual signal...
Source: The American Naturalist - September 17, 2009 Category: Zoology Tags: article Source Type: journals
Aggressive Behavior and Performance in the Tegu Lizard Tupinambis merianaeEmail this article to a colleague.
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Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract Aggression is an important component of behavior in many animals and may be crucial to providing individuals with a competitive advantage when resources are limited. Although much is known about the effects of catecholamines and hormones on aggression, relatively few studies have examined the effects of physical performance on aggression. Here we use a large, sexually dimorphic teiid lizard to test whether individuals that show high levels of physical performance (bite force) are also more aggressive toward a potential threa...
Source: Physiological and Biochemical Zoology - September 16, 2009 Category: Zoology Tags: article Source Type: journals
Muscle Metabolic Capacities and Plasma Cortisol Levels of the Male Three‐Spine Stickleback Gasterosteus aculeatus: Are There “Femme Fatale” or “Macho Male” Effects?Email this article to a colleague.
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Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract To evaluate whether decreases in muscle metabolic capacities and increases in plasma cortisol explain the effects of neighboring conspecifics on male three‐spine sticklebacks Gasterosteus aculeatus, we housed mature males alone, with a mature female, or with a rival mature male. The neighbors were separated from the focal male by a partition that allowed him to smell, see, and hear his neighbor. In the first experiment, focal males were allowed to reproduce, whereas in the second experiment, no reproduction occurred. Color...
Source: Physiological and Biochemical Zoology - September 16, 2009 Category: Zoology Tags: article Source Type: journals
Jettisoning Ballast or Fuel? Caudal Autotomy and Locomotory Energetics of the Cape Dwarf Gecko Lygodactylus capensis (Gekkonidae)Email this article to a colleague.
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We examined the effect of tail loss on locomotory costs in the Cape dwarf gecko Lygodactylus capensis (∼0.9 g) using a novel method for collecting data on small lizards, a method previously used for arthropods. We measured CO2 production during 5–10 min of exhaustive exercise (in response to stimulus) and during a 45‐min recovery period. During exercise, we measured speed (for each meter moved) as well as total distance traveled. Contrary to our expectations, tailless geckos overall expended less effort in escape running, moving both slower and for a shorter distance, compared with when they were intact. Tailless gec...
Source: Physiological and Biochemical Zoology - September 16, 2009 Category: Zoology Tags: article Source Type: journals
Macro‐ and Microgeographic Variation in Metabolism and Hormone Correlates in Big Brown Bats (Eptesicus fuscus)Email this article to a colleague.
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Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract To better understand intraspecific variation in basal metabolic rate (BMR), we examined environmental, physiological, and/or cellular bases for residual variation in BMR in big brown bats, Eptesicus fuscus. We measured BMR and plasma levels of thyroid hormone (T3) and leptin in bats captured in maternity colonies in eastern Massachusetts (MA; northern population) and in Alabama and Georgia (ALGA; southern population) to assess macrogeographic (between‐ or among‐population) and microgeographic (within‐population) variat...
Source: Physiological and Biochemical Zoology - September 16, 2009 Category: Zoology Tags: article Source Type: journals
Fish cardiorespiratory physiology in an era of climate changeEmail this article to a colleague.
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A. P. Farrell, E. J. Eliason, E. Sandblom, and T. D. Clark - This review examines selected areas of cardiovascular physiology where there have been impressive gains of knowledge and indicates fertile areas for future research. Because arterial...
Source: Canadian Journal of Zoology - September 16, 2009 Category: Zoology Source Type: journals
A model to predict fasting capacities and utilization of body energy stores in weaned Steller sea lions (Eumetopias jubatus) during periods of reduced prey availabilityEmail this article to a colleague.
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D. P. Noren, L. D. Rea, and T. R. Loughlin - The population decline of Steller sea lions (Eumetopias jubatus (Schreber, 1776)) may be linked to a decline in juvenile survivorship. Limitations in prey availability may...
Source: Canadian Journal of Zoology - September 16, 2009 Category: Zoology Source Type: journals
Diet of spotted bats (Euderma maculatum) in Arizona as indicated by fecal analysis and stable isotopesEmail this article to a colleague.
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M. L. Painter, C. L. Chambers, M. Siders, R. R. Doucett, J. O. Whitaker, Jr., and D. L. Phillips - We assessed diet of spotted bats (Euderma maculatum (J.A. Allen, 1891)) by visual analysis of bat feces and stable carbon (δ13C) and nitrogen (δ15N) isotope...
Source: Canadian Journal of Zoology - September 16, 2009 Category: Zoology Source Type: journals
Seasonal movements and home ranges of white-tailed deer in north-central South DakotaEmail this article to a colleague.
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T. W. Grovenburg, J. A. Jenks, R. W. Klaver, C. C. Swanson, C. N. Jacques, and D. Todey - Knowledge of movement patterns of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) inhabiting landscapes intensively modified by agricultural systems is important to the present and future...
Source: Canadian Journal of Zoology - September 16, 2009 Category: Zoology Source Type: journals
Sexual Selection and the Random Union of Gametes: Testing for a Correlation in Fitness between Mates in Drosophila melanogasterEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Both males and females vary in fitness. While high‐fitness males typically have greater siring success, it is not clear whether these males sire an equal fraction of offspring from all females or a disproportionately large fraction with high‐fitness females. The latter nonrandom reproductive pattern can arise as the result of sexual selection and creates a positive correlation in fitness between mates. Such a correlation, if it reflects a positive genetic correlation between mates with respect to fitness, increases the efficiency of ...
Source: The American Naturalist - September 16, 2009 Category: Zoology Tags: article Source Type: journals
Temporal synergism of neurotransmitters (serotonin and dopamine) affects testicular development in mice.Email this article to a colleague.
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This study suggests the importance of circadian organization as a function of specific temporal phase relations of neural oscillations in the maturation of gonads. Although the exact mechanism still needs to be investigated, this seems to be mediated via effects on the neuroendocrine axis.
PMID: 19765962 [PubMed - as supplied by publisher]
Source: Zoology - September 15, 2009 Category: Zoology Authors: Sethi S, Chaturvedi CM Tags: Zoology (Jena) Source Type: journals
AnnouncementsEmail this article to a colleague.
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The American Naturalist, Volume 174, Issue 4, Page iii-iv, October 2009.
Source: The American Naturalist - September 15, 2009 Category: Zoology Tags: article Source Type: journals
Do Persistently Fast‐Growing Juveniles Contribute Disproportionately to Population Growth? A New Analysis Tool for Matrix Models and Its Application to Rainforest TreesEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Plants and animals often exhibit strong and persistent growth variation among individuals within a species. Persistently fast‐growing individuals have a higher chance of reaching reproductive size, do so at a younger age, and therefore contribute disproportionately to population growth (λ). Here we introduce a new approach to quantify this “fast‐growth effect.” We propose using age‐size‐structured matrix models in which persistently fast and slow growers are distinguished as they occur in relatively young and old age classes...
Source: The American Naturalist - September 15, 2009 Category: Zoology Tags: article Source Type: journals
Food Color Preferences of Molting House Finches (Carpodacus mexicanus) in Relation to Sex and Plumage ColorationEmail this article to a colleague.
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Food color can be indicative of specific nutrients, and thus discrimination based on color can be a valuable foraging behavior. Several bird and fish species with carotenoid-based body ornamentation show color preferences for presumably carotenoid-rich red and orange foods. However, little is known within species about whether or not individuals with (or growing) more colorful ornaments show stronger food-color preferences than those with drabber coloration. Here, we examine food color preferences in house finches (Carpodacus mexicanus) [ndash] a species with sexually dichromatic and selected carotenoid coloration [ndash] ...
Source: Ethology - September 14, 2009 Category: Zoology Authors: Ana L. Bascuñán, Elizabeth A. Tourville, Matthew B. Toomey, Kevin J. McGraw Source Type: journals
Developmental plasticity, modularity, and heterochrony during the phylotypic stage of the zebra fish, Danio rerio.Email this article to a colleague.
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We studied early embryonic development of zebra fish and tested if changes in the external raising conditions could elicit phenotypic changes during the phylotypic stage which, classically, is considered as a conserved embryonic stage. In particular, we tested for internal constraints, plasticity, and heterochrony during the early embryonic development. Our tested hypotheses predict (i) no change associated with developmental stability/internal constraints, (ii) change of the rate of development associated with developmental flexibility, and (iii) heterochronic disruption of developmental pattern associated with a modu...
Source: Journal of Experimental Zoology. Part B. Molecular and Developmental Evolution - September 14, 2009 Category: Zoology Authors: Schmidt K, Starck JM Tags: J Exp Zoolog B Mol Dev Evol Source Type: journals
Flowering Life‐History Strategies Differ between the Native and Introduced Ranges of a Monocarpic PerennialEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Life‐history theory makes several key predictions about reproductive strategies on the basis of demographic vital rates, particularly the relationship between juvenile and adult survival. Two such predictions concern the optimal time to begin reproducing and whether semelparity or iteroparity is favored. I tested these life‐history predictions and explored how they might differ between the native and introduced ranges of the monocarpic perennial Cynoglossum officinale. I first compared vital rates between ranges. I then used these vi...
Source: The American Naturalist - September 14, 2009 Category: Zoology Tags: article Source Type: journals
How Different Types of Natal Experience Affect Habitat PreferenceEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: In many animals, exposure to cues in a natal habitat increases disperser preferences for those cues (natal habitat preference induction [NHPI]), but the proximate and ultimate bases for this phenomenon are obscure. We developed a Bayesian model to study how different types of experience in the natal habitat and survival to the age/stage of dispersal interact to affect a disperser’s estimate of the quality of new natal‐type habitats. The model predicts that the types of experience a disperser had before leaving its natal habitat will ...
Source: The American Naturalist - September 14, 2009 Category: Zoology Tags: article Source Type: journals
Colony Budding and its Effects on Food Allocation in the Highly Polygynous Ant, Monomorium pharaonisEmail this article to a colleague.
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To advance our understanding of the causes and the consequences of budding (colony multiplication by fragmentation of main nests), we investigated nest movement in the facultatively polydomous Pharaoh ant, Monomorium pharaonis. Demographic data revealed that Pharaoh ants are highly polygynous and have a relatively low worker to queen ratio of 12.86. Budding experiments demonstrated that the number of available bud nests has a significant effect on colony fragmentation and increasing the number of bud nests resulted in smaller colony fragments. The overall distribution among bud nests was uneven, even though there was no ev...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Grzegorz Buczkowski, Gary Bennett Source Type: journals
Selective Prey Delivery to Incubating Females by Dominant Males, but not Helpers, in the Cooperatively Breeding Green WoodhoopoeEmail this article to a colleague.
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In cooperatively breeding bird species, one of the most conspicuous helping behaviours is the provisioning of food. Many studies have considered the feeding of nestlings, but far fewer have examined feeding of incubating females, and none have looked at the types of prey delivered at this stage. Here I show that green woodhoopoe (Phoeniculus purpureus) group members selectively feed incubating females with certain prey items: the diet delivered to incubating females contains a higher proportion of caterpillars, centipedes and cockroaches than that eaten by the provisioning adults themselves. The prey items selectively deli...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Andrew N. Radford Source Type: journals
Facultative Adjustment of Brood Sex Ratio in Response to Indirect Manipulation of BehaviourEmail this article to a colleague.
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Sex allocation theory states that parents should adjust their offspring sex ratio according to the expected fitness returns from sons and daughters. Several recent studies indicate that such adaptive manipulation of offspring sex ratio is achievable, and that it may be influenced by e.g. morphological characters. Here we manipulate behaviour through interspecific cross-fostering of great tits (Parus major) and blue tits (Cyanistes caeruleus), and investigate its effect on the offspring sex ratio of adults that were themselves cross-fostered as chicks. The experience of being raised by a different species has previously bee...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Lars Erik Johannessen, Lena Kristiansen, Bo Terning Hansen, Tore Slagsvold Source Type: journals
Antipredator Responses by Native Mosquitofish to Non-Native Cichlids: An Examination of the Role of Prey NaivetéEmail this article to a colleague.
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In this study, we tested this notion by examining the antipredator response of native mosquitofish, Gambusia holbrooki, to two non-native predators found in the Everglades, the African jewelfish, Hemichromis letourneuxi, and the Mayan cichlid, Cichlasoma urophthalmus. We manipulated prey naiveté by using two mosquitofish populations that varied in their experience with the recent invader, the African jewelfish, but had similar levels of experience with the longer-established Mayan cichlid. Specifically, we tested these predictions: (1) predator hunting modes differed between the two predators, (2) predation rates would be...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Jennifer S. Rehage, Katherine L. Dunlop, William F. Loftus Source Type: journals
Diverging Cave- and River-Dwelling Newts Exert the Same Mate Preference in their Native Light ConditionsEmail this article to a colleague.
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When colonizing a new habitat, populations must adapt their sexual behaviour to new ecological constraints. Because caves display drastically different conditions from surface habitats and cave animals are deprived from visual information, hypogean populations are expected to have modified their mate preference and signalling behaviour after cave colonization. Here, we experimentally examined the female preference and the sexual behaviour of brook newts Calotriton asper from different cave and river populations, either in light or in darkness. Our results suggest that females prefer large individuals in both hypogean and e...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Amélie N. Dreiss, Olivier Guillaume, Jean Clobert Source Type: journals
Diversity of the Vocal Signals of Concave-Eared Torrent Frogs (Odorrana tormota): Evidence for Individual SignaturesEmail this article to a colleague.
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Male concave-eared torrent frogs (Odorrana tormota) have an unusually large call repertoire and have been shown to communicate ultrasonically. We investigated the individual specificity of male advertisement calls in order to explore the acoustic bases of individual recognition, which was demonstrated in an accompanying study. Vocalizations of 15 marked males were recorded in the field. A quantitative analysis of the signals revealed eight basic call-types. Two of them (the single- and multi-note long-calls) were investigated in more detail. Long-calls were characterized by pronounced and varying frequency modulation patte...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Albert S. Feng, Tobias Riede, Victoria S. Arch, Zulin Yu, Zhi-Min Xu, Xin-Jian Yu, Jun-Xian Shen Source Type: journals
The Sound of Arousal: The Addition of Novel Non-linearities Increases Responsiveness in Marmot Alarm CallsEmail this article to a colleague.
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Vocal structure should reflect vocal function. While much attention has focused on quantifying attributes of harmonic vocalizations, the vocalizations of many species also may contain non-linear phenomena such as warbles, subharmonics, biphonation, and deterministic chaos or noise. The function of these non-linearities remains enigmatic. In some species, harmonic vocalizations abruptly become 'noisy' when individuals are physiologically aroused and the sudden onset of these non-linearities could signal arousal or fear to receivers. One untested functional hypothesis is that vocalizations containing non-linearities are more...
Source: Ethology - September 13, 2009 Category: Zoology Authors: Daniel T. Blumstein, Charlotte Récapet Source Type: journals
Melanin-based Feather Colour and Moulting Latitude in a Migratory SongbirdEmail this article to a colleague.
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We examined the hypothesis that individuals moulting during migration produce relatively dull feathers compared to individuals moulting on the breeding grounds prior to migration because of the costs associated with overlapping these two activities. We estimated both the colour and moulting latitude of melanin-based feathers in barn swallows (Hirundo rustica). Moulting latitude was inferred from stable-hydrogen isotope ([delta]D) values of individuals that were known to have bred at the same site the previous year. Contrary to expectations, [delta]D values in feathers suggested that most, if not all, individuals moulted th...
Source: Ethology - September 13, 2009 Category: Zoology Authors: D. Ryan Norris, Oddmund Kleven, Arild Johnsen, T. Kurt Kyser Source Type: journals
