Zoology
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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 3.
Hatching time for monotreme immunology
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Emily S. W. Wong, Anthony T. Papenfuss, Robert D. Miller, Katherine Belov - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Evolutionary and phylogenetic significance of platypus microsatellites conserved in mammalian and other vertebrate genomesEmail this article to a colleague.
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E. Buschiazzo, N. J. Gemmell - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
The enigma of the platypus genomeEmail this article to a colleague.
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Wesley C. Warren, Frank Grützner - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Do genomic datasets resolve the correct relationship among the placental, marsupial and monotreme lineages?Email this article to a colleague.
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Gavin Huttley - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Platypus venom genes expressed in non-venom tissuesEmail this article to a colleague.
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Camilla M. Whittington, Katherine Belov - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Breeding behaviour of the platypus (Ornithorhynchus anatinus) in captivityEmail this article to a colleague.
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Margaret Hawkins, Adam Battaglia - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Reproductive strategies of the short-beaked echidna – a review with new data from a long-term study on the Tasmanian subspecies (Tachyglossus aculeatus setosus)Email this article to a colleague.
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Gemma Morrow, Niels A. Andersen, Stewart C. Nicol - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Thermoregulation in monotremes: riddles in a mosaicEmail this article to a colleague.
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Peter H. Brice - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Distribution, prevalence and persistence of mucormycosis in Tasmanian platypuses (Ornithorhynchus anatinus)Email this article to a colleague.
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Nick Gust, Joshua Griffiths, Michael Driessen, Annie Philips, Niall Stewart, Dominic Geraghty - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Population genetics of the platypus (Ornithorhynchus anatinus): a fine-scale look at adjacent river systemsEmail this article to a colleague.
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Stephen H. Kolomyjec, Josephine Y. T. Chong, David Blair, Jaime Gongora, Tom R. Grant, Christopher N. Johnson, Chris Moran - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Development of microsatellite markers for the short-beaked echidna using three different approachesEmail this article to a colleague.
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C. Vanpé, E. Buschiazzo, J. Abdelkrim, G. Morrow, S. C. Nicol, N. J. Gemmell - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Platypus venom: source of novel compoundsEmail this article to a colleague.
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Jennifer M. S. Koh, Paramjit S. Bansal, Allan M. Torres, Philip W. Kuchel - Volume 57(4)
Source: Australian Journal of Zoology - October 25, 2009 Category: Zoology Source Type: journals
Effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and visceral organ growth of suckling calvesEmail this article to a colleague.
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The objective was to evaluate effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and allometric growth of visceral organs in suckling calves. Holstein bull calves (n = 8; 3[ndash]4 days of age) were fed either a low amount (average 0.63 kgDM/day, LM) or high amount (average 1.15 kgDM/day, HM) of high protein milk replacer until they were slaughtered at 6 weeks of age. Body weight (BW) at 4, 5, and 6 weeks of age, feed intake, average daily gain, and feed efficiency were higher in the HM than LM calves. The HM group had higher plasma glucose at 3 and 4 weeks of age and in...
Source: Animal Science Journal - October 23, 2009 Category: Zoology Authors: Mitsuru KAMIYA, Masatoshi MATSUZAKI, Hideki ORITO, Yuko KAMIYA, Yoshi-nori NAKAMURA, Eisaku TSUNEISHI Source Type: journals
Inverse‐Gene‐for‐Gene Infection Genetics and Coevolutionary DynamicsEmail this article to a colleague.
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We present an alternative model, termed inverse‐gene‐for‐gene (IGFG), where pathogen infectiousness is determined by parasite recognition of host signals and/or receptors or where there is active host searching by parasites. We show that coevolutionary dynamics under IGFG are both qualitatively and quantitatively different from those of the GFG model, and we suggest that this new approach may be applicable to a range of important host‐parasite systems that are not currently catered for by the existing frameworks.
Source: The American Naturalist - October 23, 2009 Category: Zoology Tags: article ‐Note Source Type: journals
Selection, Epistasis, and Parent‐of‐Origin Effects on Deleterious Mutations across Environments in Drosophila melanogasterEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Understanding the nature of selection against deleterious alleles is central to determining how populations are affected by the constant influx of new mutations. Important progress has been made in estimating basic attributes of the distribution of selection coefficients and gene interaction effects (epistasis). Although most aspects of selection are likely to be context dependent, little is known about the effect of stress on selection and epistasis at the level of individual genes, especially in multicellular organisms. Using Drosophil...
Source: The American Naturalist - October 23, 2009 Category: Zoology Tags: article Source Type: journals
Effect of elemental nano-selenium on semen quality, glutathione peroxidase activity, and testis ultrastructure in male Boer goats.Email this article to a colleague.
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In conclusion, selenium deficiency resulted in abnormal spermatozoal mitochondria, and supplementation with nano-Se enhanced the testis Se content, testicular and semen GSH-Px activity, protected the membrane system integrity and the tight arrayment of the midpiece of the mitochondria. Further studies are required to research the novel elemental nano-Se with characterization of bioavailability and toxicity in small ruminants.
PMID: 19914014 [PubMed - as supplied by publisher]
Source: Animal Reproduction Science - October 23, 2009 Category: Zoology Authors: Shi LG, Yang RJ, Yue WB, Xun WJ, Zhang CX, Ren YS, Shi L, Lei FL Tags: Anim Reprod Sci Source Type: journals
Oscillating magnetic field disrupts magnetic orientation in Zebra finches, Taeniopygia guttataEmail this article to a colleague.
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Conclusions:
The results indicate that zebra finches use a receptor that bases on radical pair prozesses for sensing the direction of the earth magnetic field in this short distance orientation behavior.
Source: Frontiers in Zoology - October 22, 2009 Category: Zoology Authors: Nina KearyTim RuplohJoe VossPeter ThalauRoswitha WiltschkoWolfgang WiltschkoHans-Joachim Bischof Source Type: journals
Analysis of consumers' preferences and behavior with regard to horse meat using a structured survey questionnaireEmail this article to a colleague.
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In this study, a structured survey questionnaire was used to determine consumers' preferences and behavior with regard to horse meat at a horse meat restaurant located in Jeju, Korea, from October 1 to December 24, 2005. The questionnaire employed in this study consisted of 20 questions designed to characterize six general attributes: horse meat sensory property, physical appearance, health condition, origin, price, and other attributes. Of the 1370 questionnaires distributed, 1126 completed questionnaires were retained based on the completeness of the answers, representing an 82.2% response rate. Two issues were investiga...
Source: Animal Science Journal - October 22, 2009 Category: Zoology Authors: Woon Yong OH, Ji Woong LEE, Chong Eon LEE, Moon Seok KO, Jae Hong JEONG Source Type: journals
Ecological Opportunity in Adaptive Radiation of Galápagos Endemic Land SnailsEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: The classic evolutionary hypothesis of ecological opportunity proposes that both heterogeneity of resources and freedom from enemies promote phenotypic divergence as a response to increased niche availability. Although phenotypic divergence and speciation have often been inferred to be the primary consequences of the release from competition or predation that accompanies a shift to a new adaptive zone, increased phenotypic variation within species is expected to represent the first stage resulting from such a shift. Using measures of int...
Source: The American Naturalist - October 22, 2009 Category: Zoology Tags: article Source Type: journals
Flight initiation distance is differentially sensitive to the costs of staying and leaving food patches in a small-mammal preyEmail this article to a colleague.
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Patricio A. Lagos, Andrea Meier, Liliana Ortiz Tolhuysen, Rodrigo A. Castro, Francisco Bozinovic, and Luis A. Ebensperger - Escape theory predicts that a prey should flee from an approaching predator at a point in which the cost of staying equals the cost of...
Source: Canadian Journal of Zoology - October 22, 2009 Category: Zoology Source Type: journals
“Causal reasoning” in rats: A reappraisal.Email this article to a colleague.
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It has recently been argued that rats engage in causal reasoning and they do so in a way that is consistent with Bayes net theories (Blaisdell, Sawa, Leising & Waldmann, 2006). This argument was based upon the finding that the tendency of cues to elicit approach to a food-well was reduced when their presentation was contingent on lever pressing. There is, however, an alternative interpretation of the critical experimental findings that is based on the simple principle of response competition: wherein lever pressing interferes with the tendency to approach the food well. Here the authors replicated Experiments 1 and 2a of B...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Dwyer, D. M.; Starns, J.; Honey, R. C. Source Type: journals
Eye movements during list execution reveal no planning in monkeys (Macaca fascicularis).Email this article to a colleague.
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When trained on a serial-order task to respond to 5 simultaneously displayed stimuli, monkeys (Macaca fascicularis) show an elevated latency to respond to the first item (A) or the first 2 items (A and B) followed by short and uniform latencies to respond to the remaining items. This pattern has been interpreted as evidence of planning, with the long initial latency reflecting the animal planning their responses, and the subsequent short and uniform latencies reflecting the execution of the planned responses. An analysis of eye movements, however, revealed no evidence of planning. The elevated latency to item A is likely a...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Scarf, Damian; Colombo, Michael Source Type: journals
The dynamics of conditioning and extinction.Email this article to a colleague.
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Pigeons responded to intermittently reinforced classical conditioning trials with erratic bouts of responding to the conditioned stimulus. Responding depended on whether the prior trial contained a peck, food, or both. A linear persistence–learning model moved pigeons into and out of a response state, and a Weibull distribution for number of within-trial responses governed in-state pecking. Variations of trial and intertrial durations caused correlated changes in rate and probability of responding and in model parameters. A novel prediction—in the protracted absence of food, response rates can plateau above zero—was ...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Killeen, Peter R.; Sanabria, Federico; Dolgov, Igor Source Type: journals
Failure of retrospective revaluation to influence blocking.Email this article to a colleague.
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In the blocking paradigm, subjects receive reinforced presentations of a compound, AX, after reinforced presentations of A alone. Following this training, responding to X is often diminished relative to a control group, which did not receive the prior training with A. Standard associative theories of learning such as the Rescorla–Wagner model (Rescorla & Wagner, 1972) explain this effect by assuming that A and X compete for control over behavior. In contrast, theories such as the comparator hypothesis assume that learning about X is unaffected by the properties of A, but it is the expression of this learning at test that...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Dopson, Jemma C.; Pearce, John M.; Haselgrove, Mark Source Type: journals
Enhancement of responding to A after A+/AX+ training: Challenges for a comparator theory of learning.Email this article to a colleague.
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Two appetitive Pavlovian conditioning experiments with rats investigated the associative changes that A undergoes in an A+/AX+ blocking procedure. Conditioned responding to A was enhanced relative to stimulus B, which had been conditioned in isolation (B+). This result was interpreted in terms of the formation of a within-compound association between A and X. The results of Experiment 2 supported this conclusion by demonstrating that X had associative strength of its own and, furthermore, that extinguishing X resulted in a similar level of responding to A and B. These results are considered in terms of retrospective revalu...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Esber, Guillem R.; Pearce, John M.; Haselgrove, Mark Source Type: journals
Protection from latent inhibition provided by a conditioned inhibitor.Email this article to a colleague.
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Two conditioned suppression experiments with rats investigated the influence on latent inhibition of compounding a Pavlovian conditioned inhibitor with the target cue during preexposure treatment. Results were compared with those of subjects that received conventional latent inhibition training, no preexposure, or preexposure to the target cue in compound with a neutral stimulus. In Experiment 1, greater attenuation of the latent inhibition effect was observed in subjects that received target preexposure in compound with a Pavlovian conditioned inhibitor relative to subjects that received preexposure with a neutral stimulu...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: McConnell, Bridget L.; Wheeler, Daniel S.; Urcelay, Gonzalo P.; Miller, Ralph R. Source Type: journals
Contextual modulation of stimulus generalization in rats.Email this article to a colleague.
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One connectionist analysis of the acquired equivalence/distinctiveness of cues assumes that when similar compounds (e.g., AX and BX) are paired with the same outcome (e.g., food, +; or no food, -), their components come to activate the same configural unit (ABX). When these compounds are paired with different outcomes, their components will come to address different units. Here, rats received appetitive training with eight compounds (e.g., AX+, BX+, CX-, DX-, AY+, BY-, CY-, DY+) that should generate the following configural units: ABX, CDX, ADY, and BCY. In Experiment 1, rats then received aversive conditioning to A, which...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Close, James; Hahn, Ulrike; Honey, R. C. Source Type: journals
Perception of food amounts by chimpanzees (Pan troglodytes): The role of magnitude, contiguity, and wholeness.Email this article to a colleague.
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The authors investigated choice behavior by chimpanzees in five experiments involving choices between different amounts of food. Chimpanzees did not maximize the amount of food they obtained when choosing between a single 20-g banana piece and another option containing a 20-g piece and a 5-g piece. This was true even though they successfully discriminated between 20-g and 25-g banana pieces in other trials. When items in the mixed option were stacked, however, the chimpanzees chose the larger amount. Later experiments indicated that changing the magnitude of the two amounts did not change performance if the difference in m...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Beran, Michael J.; Evans, Theodore A.; Ratliff, Chasity L. Source Type: journals
Stimulus dynamics and temporal discrimination: Implications for pacemakers.Email this article to a colleague.
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The purpose of the present study was to observe the functional relationship between stimulus dynamics and stimulus duration judgments in humans. Stimulus duration was defined as the length of time that a spinning sphere appeared on a computer screen. Stimulus dynamics were defined by how quickly the sphere rotated on its y-axis. Using a logarithmic scale, a psychophysical bisection task was used to divide stimulus durations into two categories, short and long. Across three experiments, participants’ duration judgments were longer the faster the sphere was rotated. This effect was observed over both a long and short tempo...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Beckmann, Joshua S.; Young, Michael E. Source Type: journals
Human sequence learning under incidental and intentional conditions.Email this article to a colleague.
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This research explored the role that dissociable associative learning and hypothesis-testing processes may play in human sequence learning. Two 2-choice serial reaction time (SRT) tasks were conducted, 1 under incidental conditions and the other under intentional conditions. In both cases an experimental group was trained on 4 subsequences (i.e., XXX, XYY, YYX, and YXY). To control for sequential effects, sequence learning was assayed by comparing their performance to a control group that had been trained on a pseudorandom ordering, during a test phase in which both groups experienced effectively the same trial order. Unde...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Jones, F. W.; McLaren, I. P. L. Source Type: journals
Discrimination and generalization along a simple dimension: Peak shift and rule-governed responding.Email this article to a colleague.
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In 2 experiments, participants learned to discriminate between a pair of simply related, but very similar, colors in a 2-choice categorization task. They were then tested over a wider range of isoluminant hues. Over these test values, both experiments yielded a postdiscrimination gradient that was initially peak-shifted but became monotonic through the course of testing. In Experiment 2, the presence of this early peak shift and subsequent change in gradient form were related to participants’ inability to verbally characterize the difference between the training stimuli. This suggests a transition from generalization bas...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Livesey, E. J.; McLaren, I. P. L. Source Type: journals
Conditioned inhibition in the spatial domain.Email this article to a colleague.
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Using a variation on the standard procedure of conditioned inhibition (Trials A+ and AX-), rats (Rattus norvegicus) in a circular pool were trained to find a hidden platform that was located in a specific spatial position in relation to 2 individual landmarks (Trials A ? platform and B ? platform; Experiments 1a and 1b) and to 2 configurations of landmarks (Trials ABC ? platform and FGH ? platform; Experiment 2a). The rats also underwent inhibitory trials (Experiment 1: Trials AZ ? no platform; Experiment 2a: Trials CDE ? no platform) interspersed with these excitatory trials. In both experiments, subsequent test trials wi...
Source: Journal of Experimental Psychology: Animal Behavior Processes - October 22, 2009 Category: Zoology Authors: Sansa, J.; Rodrigo, T.; Santamaría, J. J.; Manteiga, R. D.; Chamizo, V. D. Source Type: journals
Smad4-dependent pathways control basement membrane deposition and endodermal cell migration at early stages of mouse developmentEmail this article to a colleague.
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Conclusions:
Smad4 functional loss results in a dramatic shift in gene expression patterns and in the endodermal cell lineage causes an excess deposition of, or an inability to breakdown and remodel, the underlying BM layer. These structural abnormalities probably disrupt reciprocal signalling between the epiblast and overlying visceral endoderm required for gastrulation.
Source: BMC Developmental Biology - Latest articles - October 21, 2009 Category: Zoology Authors: Ita CostelloChristine BiondiJennifer TaylorElizabeth BikoffElizabeth Robertson Source Type: journals
Relationship between the lactation curve and udder disease incidence in different lactation stages in first-lactation Holstein cowsEmail this article to a colleague.
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We examined the relationships between the shape of the first parity lactation curve and udder disease incidence at different stages of lactation in 538 Holstein cows. Data used were first-parity daily milk yields and treatment records. Each cow was classified according to whether or not it had had udder disease at least once over the whole lactation period or in one of three stages within the lactation period. We then examined the differences in the shapes of the lactation curves between the disease incidence and non-incidence group in each stage. Cows that had high rates of increase in milk yield and high milk yields in e...
Source: Animal Science Journal - October 20, 2009 Category: Zoology Authors: Takeshi YAMAZAKI, Hisato TAKEDA, Akiko NISHIURA, Kenji TOGASHI Source Type: journals
Duration of estrus induced after GnRH-PGF2α protocol in dairy heiferEmail this article to a colleague.
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Estrous expressions in dairy cows have been shortened and weakened. Dairy heifers, on the other hand, may not have had such changes in estrous signs as observed in cows, since they have less stresses than cows. The aim of this study was to describe the duration of estrus in a herd of dairy heifers. A total of 56 Holstein Friesian heifers estrus was synchronized using two different hormonal protocols. They were checked for primary and secondary estrous signs with the help of heat detection devices for 48 h at an interval of 4 h starting at 16.00 hour, one day after PGF2[alpha] treatment. Onset and end of standing estrus dur...
Source: Animal Science Journal - October 20, 2009 Category: Zoology Authors: Chikako YOSHIDA, Muhammad YUSUF, Toshihiko NAKAO Source Type: journals
Embryo development of porcine oocytes after injection with miniature pig sperm and their extractsEmail this article to a colleague.
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This study examined embryo development of porcine oocytes after microinjection of sperm extracts (SE) in porcine intracytoplasmic sperm injection (ICSI). SE was prepared from miniature pig sperm by a nonionic surfactant, and various concentrations (0.02, 0.04 and 0.08 mg/mL) of SE were injected into the matured oocytes with a first polar body. In the pronuclear stage, the rate of oocytes with two pronuclei and a second polar body (21.4%) in the sperm and SE (0.04 mg/mL) injection group was significantly higher (P < 0.05) compared to other groups. The rate of 2[ndash]4-cell stage in sperm and SE (0.04 mg/mL) injection group...
Source: Animal Science Journal - October 20, 2009 Category: Zoology Authors: Daizou MATSUURA, Teruo MAEDA Source Type: journals
Reproductive Value and the Stochastic Demography of Age‐Structured PopulationsEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: The dynamics of an age‐structured population in a fluctuating environment is determined by the stochastic individual contributions from annual survival and fecundity to the total reproductive value of the population the next year. All parameters required to describe the population dynamics are simple properties of the distribution of these individual demographic contributions, which we call individual reproductive value. The asymptotic population growth rate in the average environment and the demographic and environmental variances are...
Source: The American Naturalist - October 20, 2009 Category: Zoology Tags: article Source Type: journals
Behavioral avoidance of injured conspecific and predatory chemical stimuli by larvae of the aquatic caddisfly Hesperophylax occidentalisEmail this article to a colleague.
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B. G. Gall and E. D. Brodie, Jr. - Prey animals often encounter situations that hinder their ability to conduct normal fitness-enhancing behaviors. Mating and foraging are frequently interrupted by predator vigilance and avoidance,...
Source: Canadian Journal of Zoology - October 20, 2009 Category: Zoology Source Type: journals
Ras promotes cell survival by antagonizing both JNK and Hid signals in the Drosophila eyeEmail this article to a colleague.
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Conclusions:
In the Drosophila eye, Ras may protect cells from apoptosis by inhibiting both JNK and Hid activities. Surprisingly, reducing Ras activity in the wing, however, does not cause apoptosis but rather affects cell and organ size. Thus, in addition to its requirement for cell viability, Ras appears to mediate different biological roles depending on the developmental context and on the level of its expression.
Source: BMC Developmental Biology - Latest articles - October 19, 2009 Category: Zoology Authors: Yue WuYuan ZhuangMin HanTian XuKejing Deng Source Type: journals
Comparative folliculogenesis and spermatogenesis of four teleost fish from a Reservoir in south-eastern BrazilEmail this article to a colleague.
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This study provides a comparative analysis of gametogenesis of neotropical teleosts Metynnis maculatus, Megalancistrus parananus, Cichla kelberi and Satanoperca pappaterra, through histological, histochemical and histometric techniques. In the ooplasm of C. kelberi and S. pappaterra conspicuous lipid vesicles were observed, which are characteristic of pelagic eggs produced by marine fishes. Perinucleolar oocytes were identified in the testis of S. pappaterra suggesting that this species is protogynous without functional hermaphroditism, an unusual pattern for neotropical fresh-water fishes. The spermatozoa of the studied s...
Source: Acta Zoologica - October 19, 2009 Category: Zoology Authors: Yuri Simões Martins, Dimas Fernando de Moura, Gilmar Bastos Santos, Elizete Rizzo, Nilo Bazzoli Source Type: journals
A critical review of ontogenetic development in Terebellidae (Polychaeta)Email this article to a colleague.
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This study reviews the ontogenetic variability of the head, the first segments and the uncini in Terebellidae, based on primary literature and development series of four terebellid species. We test hypotheses on character homologies and indicate informative characters for future phylogenetic analyses. The prostomium, identified as the region above the prototroch band of the larva, in addition to being the region of origin of the buccal tentacles, contains a series of nerves originating from the cerebrum. The peristomium, which contains the mouth, is innervated by the stomogastric nerve and consists of upper and lower lips ...
Source: Acta Zoologica - October 19, 2009 Category: Zoology Authors: André R. S. Garraffoni, Paulo C. Lana Source Type: journals
Independence of Sexual and Anti-Predator Perceptual Functions in an Acoustic Moth: Implications for the Receiver Bias Mechanism in Signal EvolutionEmail this article to a colleague.
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The receiver bias model for the evolution of mating signals proposes that selection favors male displays that happen to stimulate a general, ancestral perception in females such that receptivity and successful courtship increase. If these male signals do arise, however, the female perception will operate in two contexts, the original, typically non-sexual, one and courtship. We may then ask whether these two functions represent the same or distinct traits, which may be under separate neural and genetic control. We studied this question in Achroia grisella, a pyralid moth species in which males attract females, with an ultr...
Source: Ethology - October 19, 2009 Category: Zoology Authors: Michael D. Greenfield, Hannah Hohendorf Source Type: journals
Bourgeois queens and high stakes games in the ant Aphaenogaster senilisEmail this article to a colleague.
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Conclusions:
Aggression is probably ritualised and contests are decided by workers based on relative queen fertility. First-born queens thus have an inherent advantage over second-born queens as they have longer to develop ovaries. Subordinates never retaliated against aggression from dominants and this lack of retaliation can be interpreted as a form of bourgeois strategy as dominants were almost always first-born. However, the lack of alternative reproductive options makes not-fighting effectively a form of suicide. High relatedness between full-sister queens means that subordinates may be better off sacrificing themselv...
Source: Frontiers in Zoology - October 18, 2009 Category: Zoology Authors: Adam CroninThibaud Monnin Source Type: journals
Using stable isotopes to track frugivory in migratory passerinesEmail this article to a colleague.
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Chantal Gagnon and Keith A. Hobson - Several species of North American migratory songbirds undergo seasonal diet shifts from insects to fruits, but this phenomenon is poorly quantified. Measurement of naturally occurring...
Source: Canadian Journal of Zoology - October 15, 2009 Category: Zoology Source Type: journals
Seasonal detection rates of river otters (Lontra canadensis) using bridge-site and random-site surveysEmail this article to a colleague.
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S. M. Crimmins, N. M. Roberts, D. A. Hamilton, and A. R. Mynsberge - Randomization of survey sites is generally desired because of its unbiased approach, but is often abandoned because of logistical constraints. This is true for river...
Source: Canadian Journal of Zoology - October 15, 2009 Category: Zoology Source Type: journals
Foods and nutritional components of diets of black bear in Rocky Mountain National Park, ColoradoEmail this article to a colleague.
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Roger A. Baldwin and Louis C. Bender - We used scat analysis to determine diets and relative nutritional values of diets for black bears (Ursus americanus Pallas, 1780) in Rocky Mountain National Park,...
Source: Canadian Journal of Zoology - October 15, 2009 Category: Zoology Source Type: journals
Association of a single nucleotide polymorphism in ribosomal protein L27a gene with marbling in Japanese Black beef cattleEmail this article to a colleague.
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Marbling, defined by the amount and distribution of intramuscular fat, is an economically important trait of beef cattle in Japan. The c2-11#2 expressed sequence tag (EST) has been previously shown to possess expression difference in musculus longissimus muscle between low-marbled and high-marbled steer groups, and to be located within genomic region of a quantitative trait locus for marbling. Thus, the ribosomal protein L27a (RPL27A) gene containing the c2-11#2 EST sequence was considered as a positional candidate for the gene responsible for marbling. In the present study, a single nucleotide polymorphism (SNP) in the pr...
Source: Animal Science Journal - October 14, 2009 Category: Zoology Authors: Takahisa YAMADA, Seiki SASAKI, Shin SUKEGAWA, Takeshi MIYAKE, Tatsuo FUJITA, Hiroyuki KOSE, Mitsuo MORITA, Youichi TAKAHAGI, Hiroshi MURAKAMI, Fumiki MORIMATSU, Yoshiyuki SASAKI Source Type: journals
Effects of incubation temperature on hatchling phenotypes in an oviparous lizard with prolonged egg retention: are the two main hypotheses on the evolution of viviparity compatible?Email this article to a colleague.
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Females of several lizard species modify their body temperature during pregnancy, probably in connection with the optimisation of hatchling phenotypes. We studied variations in the temperature selected by gravid females compared with those selected by males and non-gravid females in an oviparous population of Zootoca vivipara (Jacquin, 1797) (Squamata: Lacertidae) of Northern Spain and examined the effects of incubation temperature on the phenotypic variation of hatchlings. Cloacal temperatures of gravid females active in the field were lower than those of males and non-gravid females, as well as the temperatures selec...
Source: Zoology - October 14, 2009 Category: Zoology Authors: Rodríguez-Díaz T, González F, Ji X, Braña F Tags: Zoology (Jena) Source Type: journals
Factors affecting methane production and mitigation in ruminantsEmail this article to a colleague.
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The objectives of this review are to identify the factors affecting CH4 production in ruminants, to examine technologies for the mitigation of CH4 emissions from ruminants, and to identify areas requiring further research. The following equation for CH4 prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = [minus]17.766 + 42.793X [minus] 0.849X2, where Y is CH4 production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH4 emissions from ruminants include increasing productivity by...
Source: Animal Science Journal - October 13, 2009 Category: Zoology Authors: Masaki SHIBATA, Fuminori TERADA Source Type: journals
A Linear Model Method for Biodiversity–Ecosystem Functioning ExperimentsEmail this article to a colleague.
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The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles.
Abstract: Experiments that manipulate species richness and measure ecosystem functioning attempt to separate the effects of species richness (the number of species) from those of species identity. We introduce an experimental design that ensures that each species is selected the same number of times at each level of species richness. In combination with a linear model analysis, this approach is able to unambiguously partition the variance due to different species identities and the variance due to nonlinear species richness, a proxy measure for in...
Source: The American Naturalist - October 13, 2009 Category: Zoology Tags: article Source Type: journals
