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Zhao Zhi-Jun - - 2010
A female animal appears to approach an upper limit to the rate of sustained energy intake/metabolic rate (SusEI/MR) during lactation. However, different species of animals may respond differently to the sustainable limit. Here, we measured energy budget during lactation in female striped hamsters raising litters of natural size (Con), and ...
Gardner Andy - - 2011
In mammals, altricial birds and some invertebrates, parents care for their offspring by providing them with food and protection until independence. Although parental food provisioning is often essential for offspring survival and growth, very little is known about the conditions favouring the evolutionary innovation of this key component of care. ...
Bridge Eli S - - 2010
Because of their reliance on temporally predictable resources across large spatial scales, migratory birds may be especially vulnerable to anthropogenic climate and land-use changes. Although some long-distance migrants appear unable to adjust to phenological shifts on their wintering grounds, several short- and medium-distance migrants appear to have altered the timing ...
Hernández Emilio - - 2010
We evaluated three packing systems (PARC boxes, "GT" screen towers and "MX" screen towers) for the emergence and sexual maturation of sterile fruit flies, at three adult fly densities (1, 1.2 and 1.3 fly/cm²) and three food types. At the lowest density, results showed no significant differences in the longevity ...
Keynan Oded - - 2010
The Southern Grey Shrike (Lanius meridionalis) is a common resident along the rift valley. During 2007-2008 we studied the impaling behavior of Southern Grey Shrikes at the Shezaf nature reserve by food supplementation. Our findings indicate seasonal shifts in impaling behavior. During the winter, there was no difference between the ...
Auer Sonya K - - 2010
Compensatory or 'catch-up' growth may be an adaptive mechanism that buffers the growth trajectory of young organisms from deviations caused by reduced food availability. Theory generally assumes that rapid juvenile compensatory growth impacts reproduction only through its positive effects on age and size at maturation, but potential reproductive costs to ...
Foerster Steffen - - 2010
Because of their mediating role in the stress response and potential effects on fitness, glucocorticoid (GC) hormones are increasingly used to assess the physiological costs of environmental and behavioral variation among wild vertebrates. Identifying the proximate causes of GC variation, however, is complicated by simultaneous exposure to multiple potentially stressful ...
Golizadeh A - - 2010
The potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is an important and ubiquitous pest of potato, Solanum tuberosum L. (Solanaceae), in both field and stores in the subtropical and tropical zones. The evaluation of potato tubers for susceptibility to potato tuberworm, by measuring its life table parameters, is a valuable ...
Harding Juliana M - - 2010
Oysters (Crassostrea virginica) were a central component of the Chesapeake Bay ecosystem in 1607 when European settlers established Jamestown, VA, the first permanent English settlement in North America. These estuarine bivalves were an important food resource during the early years of the James Fort (Jamestown) settlement while the colonists were ...
BrzeziƄski Tomasz - - 2010
A high genetic variation and recurrent changes in the genetic structure have been found in many pelagic populations. However, evidence that directly links these changes to differences in the ecological performance of particular genotypes is scarce. We hypothesized that within Daphnia, the specialization of clones occurring in a particular season ...
Harrison Timothy J E - - 2010
Food availability influences multiple stages of the breeding cycle of birds, and supplementary feeding has helped in its understanding. Most supplementation studies have reported advancements of laying, whilst others, albeit less numerous, have also demonstrated fitness benefits such as larger clutches, shorter incubation periods, and greater hatching success. Relatively few ...
Jeong Jayoung - - 2010
3-Monochloropropane-1, 2-diol (or 3-chloro-1,2-propanediol, 3-MCPD) is a well-known food processing contaminant found in a wide range of foods and ingredients. It has been classified as non-genotoxic carcinogen but its carcinogenic potential in the rodents has been controversial. The carcinogenicity to B6C3F1 mice by drinking water administration was assessed over a ...
Jordão Alexandre L - - 2010
Reproduction of most insects depend on nutrients accumulated during the larval stage, but many lepidopteran species will also depend on nutrients obtained at the adult stage. Feeding at the adult stage allows the intake of carbohydrate and amino acid rich solutions, which may have an effect on the species reproduction ...
Sander P Martin - - 2010
The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body ...
Goodenough Anne E - - 2011
Phenological studies have demonstrated changes in the timing of seasonal events across multiple taxonomic groups as the climate warms. Some northern European migrant bird populations, however, show little or no significant change in breeding phenology, resulting in synchrony with key food sources becoming mismatched. This phenological inertia has often been ...
Temeles Ethan J - - 2010
Unambiguous examples of ecological causation of sexual dimorphism are rare, and the best evidence involves sexual differences in trophic morphology. We show that moderate female-biased sexual dimorphism in bill curvature is the ancestral condition in hermit hummingbirds (Phaethornithinae), and that it is greatly amplified in species such as Glaucis hirsutus ...
Fenchel Tom - - 2010
The polymorphic life history of the marine naked amoeba Flabellula baltica was studied. It can be interpreted in terms of adaptations to an environment that is patchy in time and space and it represents trade-off between longevity during starvation and the ability to initiate multiplication soon after food resource become ...
Stenyakina A - - 2010
We studied the reproductive biology of Mytella charruana to determine the potential reproductive success of this newly introduced bivalve species from Central/South America. We analyzed gonad morphology, gametogenesis, and the sex ratios of introduced populations throughout a 12 month period. In the non-native habitat M. charruana shows the same strategy ...
Temeles Ethan J - - 2010
The influence of male territorial and foraging behaviours on female choice has received little attention in studies of resource-defence mating systems even though such male behaviours are thought to affect variation in their territory quality and mating success. Here we show that female purple-throated carib hummingbirds Eulampis jugularis preferred to ...
Dammhahn Melanie - - 2010
The relationships between resource distribution, type of competition, and consequences for social organization have been formalized in the socioecological model (SEM) which predicts that ecological factors are the main determinants of female distribution. We tested this basic prediction in two solitary primates (Microcebus berthae and M. murinus) which differ in ...
van Doorn A C - - 2010
We examined the effects of extreme seasonality on the activity budget and diet of wild chacma baboons with access to a high-quality, human-derived food source. The Cape Peninsula of South Africa is unusual among nonhuman primate habitats due to its seasonal extremes in day length and climate. Winter days are ...
O'Dwyer Michael - - 2010
Since the introduction of imatinib just over a decade ago, there has been a dramatic change in the treatment and prognosis of early chronic phase chronic myeloid Leukaemia (CML). This review article focuses on recent advances, culminating in the approval of nilotinib by the US Food and Drug Administration for ...
Pereira Rui - - 2010
Juvenile hormone levels and adult diet have important effects on the attractiveness and competitiveness of male Anastrepha suspensa (Loew) (Caribbean fruit fly). Because the success of the sterile insect technique requires the release of males that can compete in the wild, these effects are of crucial importance. Laboratory and field ...
Redolfi I - - 2010
Elasmus steffani (Viggiani) (Hymenoptera: Elasmidae) is a gregarious idiobiont ectoparasitoid of Prays oleae (Bernard) (Lepidoptera: Plutellidae), an olive crop pest. In the substitute host Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), the duration of the developmental stages was approximately 11-15 days. The preoviposition was 8.9 ± 5.0 days, and oviposition lasted 30.4 ...
Smith Bradley P - - 2010
This case study examined the effect of environmental enrichment on the activity budgets of a male and female Australian Sea Lion (Neophoca cinerea) housed together at Adelaide Zoo. Using non-food-related (intrinsic) and food-related (extrinsic) enrichment objects, the study conducted an ABABA (withdrawal) experimental design over a 30-day period (180 hr). ...
Raia Pasquale - - 2010
Many small vertebrates on islands grow larger, mature later, lay smaller clutches/litters, and are less sexually dimorphic and aggressive than their mainland relatives. This set of observations is referred to as the 'Island Syndrome'. The syndrome is linked to high population density on islands. We predicted that when population density ...
Long Hongan - - 2010
Most free-living ciliates reproduce by equal fission or budding during vegetative growth. In certain ciliates, reproduction occurs inside the cyst wall, viz. reproductive cysts, but more complex reproductive strategies have generally been thought to be confined to parasitic or symbiotic species, e.g. Radiophrya spp. In addition to equal fission, asymmetric ...
Nowack Julia - - 2010
Hibernation and daily torpor are energy- and water-saving adaptations employed to survive unfavourable periods mostly in temperate and arctic environments, but also in tropical and arid climates. Heterothermy has been found in a number of mammalian orders, but within the primates so far it seems to be restricted to one ...
Devney Carol A - - 2010
Behavioral and/or developmental plasticity is crucial for resisting the impacts of environmental stressors. We investigated the plasticity of adult foraging behavior and chick development in an offshore foraging seabird, the black noddy (Anous minutus), during two breeding seasons. The first season had anomalously high sea-surface temperatures and 'low' prey availability, ...
Honarmand Mariam - - 2010
Unfavourable conditions throughout the period of parental care can severely affect growth, reproductive performance, and survival. Yet, individuals may be affected differently, depending on the developmental period during which constraints are experienced. Here we tested whether the nestling phase compared to the fledgling phase is more susceptible to nutritional stress ...
Suzuki Seizi - - 2010
Provisioning the young is an important form of insect parental care and is believed to improve the survival and growth of the young. Anisolabis maritima Bonelli (Dermaptera: Anisolabididae) is a cosmopolitan species of earwig that shows sub-social behavior in which the females tend clutches of eggs in soil burrows. The ...
Pereira Ricardo José Garcia - - 2010
Fecal samples and behavioral data were collected at a fortnightly basis during 11 months period from free-living male American kestrels living in southeast Brazil (22 degrees S latitude). The aim was to investigate the seasonal changes in testicular and adrenal steroidogenic activity and their correlation to reproductive behaviors and environmental ...
Smallegange Isabel M - - 2010
1. In response to warmer spring conditions in Central Europe many migratory bird species have shifted their timing of breeding. Environmental change has also led to warmer winters, shortening the distance between the breeding grounds of migratory birds and their overwintering areas. 2. Here, we show that in response to ...
Frost Paul C - - 2010
Environmental effects on parents can strongly affect the phenotype of their offspring, which alters the heritability of traits and the offspring's responses to the environment. We examined whether P limitation of the aquatic invertebrate, Daphnia magna, alters the responses of its offspring to inadequate P nutrition. Mother Daphnia consuming P-poor ...
Hancock Stephanie D - - 2009
Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis is a marked feature of anorexia nervosa. Using a modified version of the activity-based animal model of anorexia nervosa, we examine whether factors known to affect HPA axis activity influence the development of activity-based anorexia (ABA). Male and female rats were subjected to maternal ...
Samhouri Jameal Farouq - - 2009
Replenishment of many marine populations occurs through the entry of juveniles to adult populations following a pelagic larval stage. Because mortality during the pelagic stage is thought to be high and density independent, larval abundance and traits of individual larvae should have strong effects on overall population dynamics in marine ...
Lebl Karin - - 2010
The edible dormouse is a specialized seed predator which is highly adapted to the fluctuations of food availability caused by mast seeding of beech and oak trees. Dormice produce young just in time with maximum food availability, and can completely skip reproduction in years with a lack of seeding. Because ...
Bronson F H - - 2009
Seasonal reproduction is common among mammals at all latitudes, even in the deep tropics. This paper (i) discusses the neuroendocrine pathways via which foraging conditions and predictive cues such as photoperiod enforce seasonality, (ii) considers the kinds of seasonal challenges mammals actually face in natural habitats, and (iii) uses the ...
Carey Cynthia - - 2009
Organisms living today are descended from ancestors that experienced considerable climate change in the past. However, they are currently presented with many new, man-made challenges, including rapid climate change. Migration and reproduction of many avian species are controlled by endogenous mechanisms that have been under intense selection over time to ...
Humphrey Louise T - - 2010
Human life history incorporates early weaning, a prolonged period of post-weaning dependency and slow somatic growth, late onset of female reproduction, reduced birth spacing and a significant post-reproductive female lifespan, combined with rapid early brain growth. Weaned human offspring lack the cognitive skills and physical capacity required to locate, procure ...
van der Sman John - - 2009
The relative importance of maternal vs. juvenile food environment on juvenile performance is poorly understood, particularly for marine organisms. Here, we use a manipulative experiment to compare the influence of maternal and juvenile nutrition on early juvenile performance for a marine gastropod (Cominella virgata) with completely benthic development. Adult whelks ...
Maddox J Dylan - - 2009
Despite the general importance of replication in science, relatively few behavioral ecology studies are repeated. Here we repeat the seminal 1977 research of H. F. Howe, who found that the proportion of male nestlings at hatching in nests of Common Grackles (Quiscalus quiscula) increased as the breeding season progressed. Howe ...
Sakamaki Tetsuya - - 2010
Four cases of coprophagy and two cases of fecal inspection were identified during the 1142 h of observing wild bonobos at Wamba in the Luo Scientific Reserve in the Democratic Republic of the Congo. At least 5 females in the study group practiced coprophagy and/or fecal inspection. According to our ...
Benenson Joyce F - - 2010
Sexual selection theory predicts that additional resources will have a greater impact on males' compared with females' reproductive success. Consequently, we expected that strong cues signalling increased resource availability should augment cognitive functioning associated with long-term maximization of reproductive outcomes (inhibition, working memory) in human males. In human females, who ...
Paul M J - - 2009
Seasonally breeding animals use a combination of photic (i.e. day length) and nonphotic (e.g. food availability, temperature) cues to regulate their reproduction. How these environmental cues are integrated is not understood. To assess the potential role of two candidate neuropeptides, kisspeptin and RFamide-related peptide-3 (RFRP), we monitored regional changes in ...
Kwan Lucia - - 2010
Many laboratory speciation experiments have raised allopatric populations in different environments to determine whether reproductive isolation evolves as a byproduct of adaptation (a form of ecological speciation). Few, however, have addressed the evolution of both pre- and postmating isolation or investigated the conditions affecting the process. We present results of ...
Ruiz Mayté - - 2010
The energetic resources in an organism's environment are essential for executing a wide range of life-history functions, including immunity and reproduction. Most energetic budgets, however, are limited, which can lead to trade-offs among competing functions. Increasing reproductive effort tends to decrease immunity in many cases, and increasing total energy via ...
Ban Syuhei - - 2009
Daphnia pulex were reared in 50 ml flasks, each containing 1, 20 or 40 individuals, which were serially connected with a 20-mum mesh screens between, in order to examine the effect of physical interference due to crowding on shifts of life history traits throughout two consecutive generations. A flow-through system, ...
Ross Alastair B - - 2009
OBJECTIVES: To compare the nutrient and food intake of Sami still engaged in reindeer herding (traditional lifestyle or reindeer-herding Sami [RS]) and Sami not involved in reindeer herding (industrialized lifestyle or non-reindeer-herding Sami [NRS]) with other northern Swedish populations. STUDY DESIGN: Cross-sectional analysis of data from a prospective cardiovascular intervention ...
Kuenzi Amy J - - 2009
Deer mice (Peromyscus maniculatus) are the principal reservoir host of Sin Nombre virus (SNV). Deer mice use a wide variety of habitats including peridomestic settings in and around human dwellings, their presence in and around homes has been implicated as a risk factor for acquiring Hantavirus Pulmonary Syndrome. Deer mice ...
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