Dr. Kim Jensen, PhD - Aarhus University

Dr. Kim Jensen

PhD

Aarhus University

Aarhus, Jutland | Denmark

Main Specialties: Biology

Additional Specialties: Insect physiology and behaviour, nutritional ecology, adaptation

ORCID logohttps://orcid.org/0000-0003-0261-3831


Top Author

Dr. Kim Jensen, PhD - Aarhus University

Dr. Kim Jensen

PhD

Introduction

I am an evolutionary ecologist with high interest in behaviour and physiology, and in adaptation and acclimation to environmental conditions. I work broadly across species at topics including predator-prey interactions, balancing of nutrients, reproductive performance, sexual selection, and life-history trade-offs.

Primary Affiliation: Aarhus University - Aarhus, Jutland , Denmark

Specialties:

Additional Specialties:

Research Interests:


View Dr. Kim Jensen’s Resume / CV

Education

Jun 2010
University of Oxford
D.Phil
Department of Zoology
Sep 2002 - Jun 2005
Aarhus Universitet
M.Sc
Department of Bioscience
Sep 1998 - Aug 2002
Aarhus Universitet
B.Sc
Department of Bioscience

Experience

Apr 2016 - Apr 2017
Aalborg Universitet
Postdoc
Department of Chemistry and Bioscience
Mar 2016
North Carolina State University
Postdoc
Department of Entomology and Plant Pathology
Oct 2013
University of Exeter
Postdoc
Centre for Ecology and Conservation
Nov 2007 - Nov 2008
University of Sydney
D.Phil Student
School of Biological Sciences
Jun 2005 - Jun 2007
University of Oxford
Laboratory Technician
Department of Zoology

Publications

35Publications

387Reads

18Profile Views

71PubMed Central Citations

Prey-specific experience affects prey preference and time to kill in the soil predatory mite Gaeolaelaps aculeifer Canestrini

Biological Control

Generalist predators potentially have access to a wide array of prey, but it is little studied how experience with specific prey affects preference for this prey. In particular, it is unknown how experience with pest prey affects predator foraging decisions in cases where the pest is nutritious but protected by a repelling, potentially deadly defence. We investigated preference of the soil predatory mite Gaeolaelaps aculeifer Canestrini for the risky pest springtail Protaphorura fimata Gisin relative to the safe non-pest springtail Folsomia candida Willem. Egg production under foraging on live or dead individuals of either prey showed that the two species had equal nutritional quality for G. aculeifer, but indicated that live F. candida were more difficult to catch than live P. fimata. Importantly, some G. aculeifer were killed by P. fimata defence secretions, demonstrating that live P. fimata are risky prey. Preference for P. fimata was generally high when mites were given a choice between a live individual of either prey, but this preference was reduced following exposure to live individuals of P. fimata. Furthermore, fewer G. aculeifer killed a prey and time until kill was longer after experience with live P. fimata. These findings indicate that live P. fimata induced a partial aversion on G. aculeifer during exposure. Our study shows that generalist predators can reduce their preference for risky prey following exposure. This indicates that generalist predators used in biological control against risky prey are most efficient against this prey if not exposed to it prior to release.

https://pure.au.dk/portal/en/publications/preyspecific-experience-affects-prey-preference-and-time-to-kill-in-the-soil-predatory-mite-gaeolaelaps-aculeifer-canestrini(017fe5cb-4dbc-4376-af90-0724dfbd5a70).html

View Article
2019

Prey-specific impact of cold pre-exposure on kill rate and reproduction.

J Anim Ecol 2019 02 2;88(2):258-268. Epub 2018 Nov 2.

Department of Bioscience, Section for Soil Ecology and Ecotoxicology, Aarhus University, Silkeborg, Denmark.

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http://doi.wiley.com/10.1111/1365-2656.12916
Publisher Site
http://dx.doi.org/10.1111/1365-2656.12916DOI Listing
February 2019
32 Reads
4.504 Impact Factor

Interactive effects of temperature and time on cold tolerance and spring predation in overwintering soil predatory mites (Gaeolaelaps aculeifer Canestrini)

Biological Control

Soil living mites have large potential as biocontrol agents against soil-dwelling pests, but little is known about their ecological and ecophysiological responses to cold. We investigated the interactive effects of acclimation temperature and time on cold tolerance in the laelapid mite Gaeolaelaps aculeifer Canestrini after exposure to 5, 10, 15, or 20 °C for 1, 4, or 8 days. Another group of mites were subjected to simulated winter by gradually lowering the temperature from 20 to 0.8 °C during three months, while measuring tolerance to -2 and -5 °C as well as supercooling point and melt onset temperature of body fluids at start (20 °C; “summer”), at 5 °C (“autumn”), and at 0.8 °C (“winter”). A third group was kept at constant 10 °C as a constant mild cold comparison. We found a strong interaction between exposure temperature and time on cold tolerance, with rapid cold hardening after 24 h at 5 °C but increasing cold acclimation at 10 °C. During simulated winter, tolerance to -2 °C was high after two months at 4.1 °C, but then decreased to intermediate levels after another month at 0.8 °C. The supercooling point did not change over the simulated winter, but melt onset temperature was lowered after 0.8 °C exposure. Mites preyed and reproduced readily following simulated winter, but at lower rates than if kept at constant 10 °C. Our study indicates that G. aculeifer can overwinter following release, and suggests that cold storage is advantageous before inoculative release in early spring.

https://pure.au.dk/portal/en/publications/interactive-effects-of-temperature-and-time-on-cold-tolerance-and-spring-predation-in-overwintering-soil-predatory-mites-gaeolaelaps-aculeifer-canestrini(d1f17467-4f7b-46cd-b4c8-5ca642e8a1ce).html

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February 2019
7 Reads

Increased lipid accumulation but not reduced metabolism explains improved starvation tolerance in cold-acclimated arthropod predators.

Naturwissenschaften 2018 Nov 19;105(11-12):65. Epub 2018 Nov 19.

Department of Bioscience, Section for Zoophysiology, Aarhus University, C.F. Møllers Allé 3, Building 1131, 8000, Aarhus C, Denmark.

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http://dx.doi.org/10.1007/s00114-018-1593-6DOI Listing
November 2018
14 Reads
1.971 Impact Factor

Genotype-by-sex-by-diet interactions for nutritional preference, dietary consumption, and lipid deposition in a field cricket.

Heredity (Edinb) 2018 10 8;121(4):361-373. Epub 2018 Aug 8.

Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Penryn, Cornwall, TR10 9FE, UK.

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http://dx.doi.org/10.1038/s41437-018-0130-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6133965PMC
October 2018
44 Reads
3.810 Impact Factor

Are commercial stocks of biological control agents genetically depauperate? - a case study on the pirate bug Orius majusculus

Biol Control 127;31-38

Biological Control

Predatory arthropods are increasingly used in biological control of insect pests. For this purpose, control agents are produced commercially in large quantities for release in crops. The production stocks, however, may have undergone numerous population bottlenecks and may have been exposed to artificial selection pressures in the production facilities. Accordingly, commercial populations may be experiencing loss of genetic variation through inbreeding and genetic drift, which may reduce fitness and biocontrol efficiency. In the present study we investigated whether populations of the pirate bug Orius majusculus (Reuter) purchased from three European companies differed in a range of performance traits including predation rate, starvation tolerance, body size, locomotor activity, and heat tolerance. Furthermore, we crossed all populations pairwise and tested whether outcrossed F2 hybrid offspring had increased performance compared to the parental populations, as would be expected if they were genetically distinct and depauperate. Transcriptome sequencing (RNA-seq) revealed similar overall levels of genetic variation among commercial populations, but also evidence for genetic differentiation. Generally, females performed better across phenotypic traits than males. F2 hybrid offspring differed from parental populations in a highly trait- and sex specific manner. Although F2 hybrids performed better than parental populations in some traits, the results of the present study do not provide conclusive evidence that crossing of different commercial stock populations of O. majusculus improve the genetic quality and performance of this species as a biological control agent.

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August 2018
19 Reads

Little evidence for intralocus sexual conflict over the optimal intake of nutrients for life span and reproduction in the black field cricket Teleogryllus commodus

Evolution 71;2159-2177

Evolution

There is often large divergence in the effects of key nutrients on life span (LS) and reproduction in the sexes, yet nutrient intake is regulated in the same way in males and females given dietary choice. This suggests that the sexes are constrained from feeding to their sex-specific nutritional optima for these traits. Here, we examine the potential for intralocus sexual conflict (IASC) over optimal protein and carbohydrate intake for LS and reproduction to constrain the evolution of sex-specific nutrient regulation in the field cricket, Teleogryllus commodus. We showclearsexdifferencesintheeffectsofproteinandcarbohydrateintakeonLSand reproduction and strong positive genetic correlations between the sexes for the regulated intake of these nutrients. However, the between-sex additive genetic covariance matrix had very little effect on the predicted evolutionary response of nutrient regulation in the sexes. Thus, IASC appears unlikely to act as an evolutionary constraint on sex-specific nutrient regulation in T. commodus. This finding is supported by clear sexual dimorphism in the regulated intake of these nutrients under dietary choice. However, nutrient regulation did not coincide with the nutritional optima for LS or reproduction in either sex, suggesting that IASC is not completely resolved in T. commodus.

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November 2017
19 Reads

Breeding and maintaining high-quality insects

Insects as Food and Feed: from Production to Consumption

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September 2017
17 Reads

Cold acclimation reduces predation rate and reproduction but increases cold- and starvation tolerance in the predatory mite Gaeolaelaps aculeifer Canestrini

Biological Control

Ectotherms respond to their thermal environments by physiological acclimation, which increases tolerance to thermal extremes and may increase field performance. However, acclimation often has costs, and increased performance in some traits may be associated with reduced performance in other traits due to trade-offs. We investigated effects of thermal acclimation on predation, reproduction, starvation tolerance, and locomotor activity in the predatory mite Gaeolaelaps aculeifer Canestrini at 10, 15, and 20 degrees C after seven days of exposure to either of the same three temperatures, following rearing at 20 degrees C. To test for effects of cold acclimation on cold tolerance, another set of mites were acclimated at each of the three temperatures over four days including an additional group at 5 degrees C, and survival was assayed following a 24 h exposure to -2 degrees C. Our results showed highest cold-and starvation tolerance but lowest predation and reproduction across test temperatures in mites acclimated to 10 degrees C. These relationships were intermediate after 15 degrees C acclimation and opposite after 20 degrees C acclimation. Locomotor activity was unaffected by acclimation temperature. Since predation and reproduction of G. aculeifer are lowered across temperatures after cold acclimation, we recommend keeping cultures at 20 degrees C without cold exposure until release in the field when used against heavy pest infestations. However, if using G. aculeifer to keep small infestations minimized, we recommend using cold acclimated mites that better tolerate low temperature and low prey availability. Such thermal and metabolic robustness could be advantageous if predatory control agents are introduced in agroecosystems in early spring to prevent establishment of pest populations.

https://pure.au.dk/portal/en/publications/cold-acclimation-reduces-predation-rate-and-reproduction-but-increases-cold-and-starvation-tolerance-in-the-predatory-mite-gaeolaelaps-aculeifer-canestrini(1d842cec-6ce6-4eb8-9866-53e3f6d41ac2).html

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September 2017
18 Reads

Persistance of a sugar-rejecting cockroach genotype under various dietary regimes

Sci. Rep. 7:46361

Scientific Reports

Glucose-aversion is a heritable trait that evolved in a number of German cockroach (Blattella germanica L.) populations in response to strong selection with glucose-containing insecticide baits. However, in the absence of glucose-containing bait, glucose-averse (GA) cockroaches have lower performance than wild-type (WT) cockroaches in several fitness-determining traits. We allocated 48 caged populations initiated with homozygous GA and WT adults to four dietary treatments consisting of either pure rodent chow, rodent chow mixed to yield a content of either 20% glucose or 20% fructose, or a treatment consisting of choice between the 20% glucose- and the 20% fructose-containing food. After 6 months we found significantly higher frequency of WT individuals in populations restricted to the 20% glucose food, and after 12 months all dietary treatments contained significantly more WT individuals than expected. In accompanying experiments, we found lower survival and longer development time of GA nymphs restricted to glucose-containing food. We furthermore found evidence for assortative mating of females with males from their own genotype, with significant differences within WT cockroaches. Our study shows experimental evidence that within heterogeneous populations, WT German cockroaches will over time prevail in abundance over GA individuals, even when glucose is not a dietary component.

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May 2017
19 Reads

The complex interplay between macronutrient intake, cuticular hydrocarbon expression and mating success in male decorated crickets

J. Evol. Biol. 30:711-727

Journal of Evolutionary Biology

The condition dependence of male sexual traits plays a central role in sexual selection theory. Relatively little, however, is known about the condition dependence of chemical signals used in mate choice and their subsequent effects on male mating success. Furthermore, few studies have isolated the specific nutrients responsible for condition-dependent variation in male sexual traits. Here, we used nutritional geometry to determine the effect of protein (P) and carbohydrate (C) intake on male cuticular hydrocarbon (CHC) expression and mating success in male decorated crickets (Gryllodes sigillatus). We show that both traits are maximized at a moderate-to-high intake of nutrients in a P:C ratio of 1 : 1.5. We also show that female precopulatory mate choice exerts a complex pattern of linear and quadratic sexual selection on this condition-dependent variation in male CHC expression. Structural equation modelling revealed that although the effect of nutrient intake on mating success is mediated through condition-dependent CHC expression, it is not exclusively so, suggesting that other traits must also play an important role. Collectively, our results suggest that the complex interplay between nutrient intake, CHC expression and mating success plays an important role in the operation of sexual selection in G. sigillatus.

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April 2017
20 Reads

Effects of foraging distance on macronutrient balancing and performance in the German cockroach Blattella germanica

220;304-311

Journal of Experimental Biology

The German cockroach (Blattella germanica L.) is an excellent model omnivore for studying the effect of foraging effort on nutrient balancing behavior and physiology, and its consequences for performance. We investigated the effect of foraging distance on individual German cockroaches by providing two foods differing in protein-to-carbohydrate ratio at opposite ends of long containers or adjacent to each other in short containers. Each food was nutritionally imbalanced, but the two foods were nutritionally complementary, allowing optimal foraging by selective feeding from both foods. We measured nutrient-specific consumption in fifth instar nymphs and newly eclosed females foraging at the two distances, hypothesizing that individuals foraging over longer distance would select more carbohydrate-biased diets to compensate for the energetic cost of locomotion. We then determined dry mass growth and lipid accumulation in the nymphs as well as mass gain and the length of basal oocytes in the adult females as an estimate of sexual maturation. Nymphs foraging over longer distance accumulated less lipid relative to total dry mass growth, but contrary to our predictions their protein intake was higher and they accumulated more structural mass. In concordance, adult females foraging over longer distance gained more body mass and matured their oocytes faster. Our results show a positive effect of foraging distance on fitness-related parameters at two life stages, in both cases involving increased consumption of specific nutrients corresponding to requirements at the respective life stage.

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January 2017
22 Reads

Dietary choice for a balanced nutrient intake increases the mean and reduces the variance in the reproductive performance of male and female cockroaches

Ecology and Evolution

Sexual selection may cause dietary requirements for reproduction to diverge across the sexes and promote the evolution of different foraging strategies in males and females. However, our understanding of how the sexes regulate their nutrition and the effects that this has on sex-specific fitness is limited. We quantified how protein (P) and carbohydrate (C) intakes affect reproductive traits in male (pheromone expression) and female (clutch size and gestation time) cockroaches (Nauphoeta cinerea). We then determined how the sexes regulate their intake of nutrients when restricted to a single diet and when given dietary choice and how this affected expression of these important reproductive traits. Pheromone levels that improve male attractiveness, female clutch size and gestation time all peaked at a high daily intake of P:C in a 1:8 ratio. This is surprising because female insects typically require more P than males to maximize reproduction. The relatively low P requirement of females may reflect the action of cockroach endosymbionts that help recycle stored nitrogen for protein synthesis. When constrained to a single diet, both sexes prioritized regulating their daily intake of P over C, although this prioritization was stronger in females than males. When given the choice between diets, both sexes actively regulated their intake of nutrients at a 1:4.8 P:C ratio. The P:C ratio did not overlap exactly with the intake of nutrients that optimized reproductive trait expression. Despite this, cockroaches of both sexes that were given dietary choice generally improved the mean and reduced the variance in all reproductive traits we measured relative to animals fed a single diet from the diet choice pair. This pattern was not as strong when compared to the single best diet in our geometric array, suggesting that the relationship between nutrient balancing and reproduction is complex in this species.

http://pure.au.dk/portal/en/publications/dietary-choice-for-a-balanced-nutrient-intake-increases-the-mean-and-reduces-the-variance-in-the-reproductive-performance-of-male-and-female-cockroaches(001653d9-985a-4b7a-b0b0-e8aac502d2c1).html

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July 2016
20 Reads

Gustatory adaptation affects sexual maturation in male German cockroaches, Blattella germanica

Physiological Entomology

Adaptations to hazardous environmental factors are essential for survival, although they may be maladaptive in conditions where the hazard is absent. In German cockroach (Blattella germanica L.) populations, glucose aversion has evolved rapidly in response to glucose-containing insecticidal baits, but little is known about the consequences of this behaviour in the absence of bait. In the present study, glucose-averse (GA) and wild-type (WT) male German cockroaches are restricted to a range of nutritionally defined diets containing either glucose or fructose as the sole carbohydrate source, and time to first expression of courtship is measured by stimulating the male antennae daily with isolated antennae from receptive, 6-day-old females. Glucose-averse males that are restricted to glucose-containing diets mature their courtship responses significantly later than GA males restricted to fructose-containing diets, whereas there is no difference in maturation of courtship responses between GA males restricted to fructose-containing diets and WT males restricted to diets containing either sugar type. Glucose-averse males furthermore respond later to GA female antennae than to WT female antennae, all from 6-day-old females. This suggests that GA females are less sexually stimulating, and the results are also consistent with earlier findings showing that GA females contain less developed oocytes than WT females at this age. These findings demonstrate that an adaptive gustatory mutation conferring protection from a toxin may have comparatively detrimental effects under conditions where the toxin has vanished, both by delaying female sexual maturation and signalling and by delaying male sexual maturation and courtship under conditions where glucose is a major energy source.

http://pure.au.dk/portal/en/publications/gustatory-adaptation-affects-sexual-maturation-in-male-german-cockroaches-blattella-germanica(ef75eb48-961f-4e0c-bad5-6d77bee849bf).html

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March 2016
21 Reads

Macronutrient intake regulates sexual conflict in decorated crickets

J. Evol. Biol. 29:395-406

Journal of Evolutionary Biology

Sexual conflict results in a diversity of sex-specific adaptations, including chemical additions to ejaculates. Male decorated crickets (Gryllodes sigillatus) produce a gelatinous nuptial gift (the spermatophylax) that varies in size and free amino acid composition, which influences a female's willingness to fully consume this gift. Complete consumption of this gift maximizes sperm transfer through increased retention of the sperm-containing ampulla, but hinders post-copulatory mate choice. Here, we examine the effects of protein (P) and carbohydrate (C) intake on the weight and amino acid composition of the spermatophylax that describes its gustatory appeal to the female, as well as the ability of this gift to regulate sexual conflict via ampulla attachment time. Nutrient intake had similar effects on the expression of these traits with each maximized at a high intake of nutrients with a P : C ratio of 1 : 1.3. Under dietary choice, males actively regulated their nutrient intake but this regulation did not coincide with the peak of the nutritional landscape for any trait. Our results therefore demonstrate that a balanced intake of nutrients is central to regulating sexual conflict in G. sigillatus, but males are constrained from reaching the optima needed to bias the outcome of this conflict in their favour.

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February 2016
20 Reads

Suboptimal nutrient balancing despite dietary choice in glucose-averse German cockroaches, Blattella germanica.

J Insect Physiol 2015 Oct 2;81:42-7. Epub 2015 Jul 2.

Department of Entomology and the W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695-7613, USA.

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http://dx.doi.org/10.1016/j.jinsphys.2015.07.001DOI Listing
October 2015
17 Reads
1 Citation
2.470 Impact Factor

Sex-specific effects of protein and carbohydrate intake on reproduction but not lifespan in Drosophila melanogaster.

Aging Cell 2015 Aug 23;14(4):605-15. Epub 2015 Mar 23.

Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall Campus, Penryn, TR10 9EZ, UK.

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http://dx.doi.org/10.1111/acel.12333DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4531074PMC
August 2015
48 Reads
21 Citations
6.340 Impact Factor

Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability.

Proc Biol Sci 2015 Mar;282(1802)

Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Tremough Campus, Penryn TR10 9EZ, UK

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http://dx.doi.org/10.1098/rspb.2014.2144DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4344140PMC
March 2015
20 Reads
13 Citations
5.051 Impact Factor

Nutrient-specific compensatory feeding in a mammalian carnivore, the mink, Neovison vison.

Br J Nutr 2014 Oct 20;112(7):1226-33. Epub 2014 Aug 20.

Department of Bioscience,Ecology and Genetics, Aarhus University,8000Aarhus C,Denmark.

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http://dx.doi.org/10.1017/S0007114514001664DOI Listing
October 2014
24 Reads
3 Citations
3.453 Impact Factor

Balancing of specific nutrients and subsequent growth and body composition in the slug Arion lusitanicus.

Physiol Behav 2013 Oct 6;122:84-92. Epub 2013 Sep 6.

Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK; School of Biological Sciences, University of Sydney, Heydon-Laurence Building A08, Sydney, NSW 2006, Australia; Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK. Electronic address:

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http://dx.doi.org/10.1016/j.physbeh.2013.08.023DOI Listing
October 2013
18 Reads
2.980 Impact Factor

Optimal foraging for specific nutrients in predatory beetles.

Proc Biol Sci 2012 Jun 11;279(1736):2212-8. Epub 2012 Jan 11.

Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.

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http://dx.doi.org/10.1098/rspb.2011.2410DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3321704PMC
June 2012
14 Reads
22 Citations
5.051 Impact Factor

Prey nutrient composition has different effects on Pardosa wolf spiders with dissimilar life histories.

Oecologia 2011 Mar 26;165(3):577-83. Epub 2010 Oct 26.

Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK.

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http://dx.doi.org/10.1007/s00442-010-1811-1DOI Listing
March 2011
21 Reads
4 Citations
3.093 Impact Factor

Metabolic consequences of feeding and fasting on nutritionally different diets in the wolf spider Pardosa prativaga.

J Insect Physiol 2010 Sep 19;56(9):1095-100. Epub 2010 Mar 19.

Department of Zoology, University of Oxford, Oxford, UK.

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http://dx.doi.org/10.1016/j.jinsphys.2010.03.001DOI Listing
September 2010
16 Reads
6 Citations
2.470 Impact Factor

Top co-authors

John Hunt
John Hunt

Columbia University

7
Stephen J Simpson
Stephen J Simpson

The University of Sydney

5
David Mayntz
David Mayntz

University of Oxford

5
David Raubenheimer
David Raubenheimer

The University of Sydney

3
James Rapkin
James Rapkin

College of Life and Environmental Sciences

3
Martin Holmstrup
Martin Holmstrup

National Environmental Research Institute

2
Clarissa M House
Clarissa M House

University of Exeter

2
Johannes Overgaard
Johannes Overgaard

Aarhus University

2