@article{jensen_silverman_2018, title={Frequently mated males have higher protein preference in German cockroaches}, volume={29}, ISSN={["1465-7279"]}, DOI={10.1093/beheco/ary104}, abstractNote={Protein is an abundant nutrient in sperm, and males therefore expend protein every time they mate. In addition, many males provide the female with a nitrogen-rich nuptial gift during mating, which often increases female fertility by supplementing her pool of limiting nutrients. However, it is unknown whether males compensate for the nitrogen cost of mating by increasing their preference for protein, which would facilitate the production of new sperm and nuptial gift material. Using artificial diets, we investigated whether male German cockroaches (Blattella germanica) would compensate for nitrogen expenses of mating by increasing protein preference when given the opportunity to self-select their diet from complementary foods differing only in protein and carbohydrate content. We distributed adult males across 4 mating regimes differing in the frequency of mating opportunities with receptive females and measured protein and carbohydrate consumption as well as reproductive output over the lifespan of each male. Receptive females were either never available (no mating opportunity), or they were available overnight at a frequency of each 28 days (rare mating opportunities), each 14 days (occasional mating opportunities), or each 7 days (frequent mating opportunities). Males selected highly carbohydrate-biased diets. However, males that mated more frequently had higher consumption and reproduction and self-selected higher lifetime protein to carbohydrate ratios. Our study demonstrates that male German cockroaches actively select a more protein-biased diet that compensates for their nutritional requirements following mating. The study shows that male mating significantly affects foraging decisions for specific nutrients to compensate for the expenses of mating.}, number={6}, journal={BEHAVIORAL ECOLOGY}, author={Jensen, Kim and Silverman, Jules}, year={2018}, pages={1453–1461} }
 @article{jensen_wada-katsumata_schal_silverman_2017, title={Persistence of a sugar-rejecting cockroach genotype under various dietary regimes}, volume={7}, ISSN={2045-2322}, url={http://dx.doi.org/10.1038/srep46361}, DOI={10.1038/srep46361}, abstractNote={AbstractGlucose-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.}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Jensen, Kim and Wada-Katsumata, Ayako and Schal, Coby and Silverman, Jules}, year={2017}, month={Apr} }
 @article{noreika_madsen_jensen_toft_2016, title={Balancing of lipid, protein, and carbohydrate intake in a predatory beetle following hibernation, and consequences for lipid restoration}, volume={88}, journal={Journal of Insect Physiology}, author={Noreika, N. and Madsen, N. E. L. and Jensen, K. and Toft, S.}, year={2016}, pages={1–9} }
 @article{bunning_bassett_clowser_rapkin_jensen_house_archer_hunt_2016, title={Dietary choice for a balanced nutrient intake increases the mean and reduces the variance in the reproductive performance of male and female cockroaches}, volume={6}, number={14}, journal={Ecology and Evolution}, author={Bunning, H. and Bassett, L. and Clowser, C. and Rapkin, J. and Jensen, K. and House, C. M. and Archer, C. R. and Hunt, J.}, year={2016}, pages={4711–4730} }
 @article{ko_jensen_schal_silverman_2016, title={Effects of foraging distance on macronutrient balancing and performance in the German cockroach Blattella germanica}, volume={220}, ISSN={0022-0949 1477-9145}, url={http://dx.doi.org/10.1242/jeb.146829}, DOI={10.1242/jeb.146829}, abstractNote={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.}, number={2}, journal={The Journal of Experimental Biology}, publisher={The Company of Biologists}, author={Ko, Alexander E. and Jensen, Kim and Schal, Coby and Silverman, Jules}, year={2016}, month={Nov}, pages={304–311} }
 @article{jensen_ko_schal_silverman_2016, title={Insecticide resistance and nutrition interactively shape life-history parameters in German cockroaches}, volume={6}, ISSN={2045-2322}, url={http://dx.doi.org/10.1038/srep28731}, DOI={10.1038/srep28731}, abstractNote={AbstractFitness-related costs of evolving insecticide resistance have been reported in a number of insect species, but the interplay between evolutionary adaptation to insecticide pressure and variable environmental conditions has received little attention. We provisioned nymphs from three German cockroach (Blattella germanica L.) populations, which differed in insecticide resistance, with either nutritionally rich or poor (diluted) diet throughout their development. One population was an insecticide-susceptible laboratory strain; the other two populations originated from a field-collected indoxacarb-resistant population, which upon collection was maintained either with or without further selection with indoxacarb. We then measured development time, survival to the adult stage, adult body size, and results of a challenge with indoxacarb. Our results show that indoxacarb resistance and poor nutritional condition increased development time and lowered adult body size, with reinforcing interactions. We also found lower survival to the adult stage in the indoxacarb-selected population, which was exacerbated by poor nutrition. In addition, nutrition imparted a highly significant effect on indoxacarb susceptibility. This study exemplifies how poor nutritional condition can aggravate the life-history costs of resistance and elevate the detrimental effects of insecticide exposure, demonstrating how environmental conditions and resistance may interactively impact individual fitness and insecticide efficacy.}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Jensen, Kim and Ko, Alexander E. and Schal, Coby and Silverman, Jules}, year={2016}, month={Jun} }
 @article{house_jensen_rapkin_lane_okada_hosken_hunt_2016, title={Macronutrient balance mediates the growth of sexually selected weapons but not genitalia in male broad-horned beetles}, volume={30}, number={5}, journal={Functional Ecology}, author={House, C. M. and Jensen, K. and Rapkin, J. and Lane, S. and Okada, K. and Hosken, D. J. and Hunt, J.}, year={2016}, pages={769–779} }
 @article{rapkin_jensen_lane_house_sakaluk_hunt_2016, title={Macronutrient intake regulates sexual conflict in decorated crickets}, volume={29}, number={2}, journal={Journal of Evolutionary Biology}, author={Rapkin, J. and Jensen, K. and Lane, S. M. and House, C. M. and Sakaluk, S. K. and Hunt, J.}, year={2016}, pages={395–406} }
 @article{jensen_schal_silverman_2015, title={Adaptive contraction of diet breadth affects sexual maturation and specific nutrient consumption in an extreme generalist omnivore}, volume={28}, ISSN={1010-061X}, url={http://dx.doi.org/10.1111/jeb.12617}, DOI={10.1111/jeb.12617}, abstractNote={AbstractAnimals balance their intake of specific nutrients, but little is known about how they do so when foraging in an environment with toxic resources and whether toxic foods promote adaptations that affect life history traits. In German cockroach (Blattella germanica) populations, glucose aversion has evolved in response to glucose‐containing insecticidal baits. We restricted newly eclosed glucose‐averse (GA) and wild‐type (WT) female cockroaches to nutritionally defined diets varying in protein‐to‐carbohydrate (P : C) ratio (3 : 1, 1 : 1, or 1 : 3) or gave them free choice of the 3 : 1 and 1 : 3 diets, with either glucose or fructose as the sole carbohydrate source. We measured consumption of each diet over 6 days and then dissected the females to measure the length of basal oocytes in their ovaries. Our results showed significantly lower consumption by GA compared to WT cockroaches when restricted to glucose‐containing diets, but also lower fructose intake by GA compared to WT cockroaches when restricted to high fructose diets or given choice of fructose‐containing diets. Protein intake was regulated tightly regardless of carbohydrate intake, except by GA cockroaches restricted to glucose‐containing diets. Oocyte growth was completely suppressed in GA females restricted to glucose‐containing diets, but also significantly slower in GA than in WT females restricted to fructose‐containing diets. Our findings suggest that GA cockroaches have adapted to reduced diet breadth through endocrine adjustments which reduce requirements for energetic fuels. Our study illustrates how an evolutionary change in the chemosensory system may affect the evolution of other traits that govern animal life histories.}, number={4}, journal={Journal of Evolutionary Biology}, publisher={Wiley}, author={Jensen, K. and Schal, C. and Silverman, J.}, year={2015}, month={Mar}, pages={906–916} }
 @article{bunning_rapkin_belcher_archer_jensen_hunt_2015, title={Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability}, volume={282}, number={1802}, journal={Proceedings of the Royal Society of London. Series B}, author={Bunning, H. and Rapkin, J. and Belcher, L. and Archer, C. R. and Jensen, K. and Hunt, J.}, year={2015} }
 @article{jensen_schal_silverman_2015, title={Suboptimal nutrient balancing despite dietary choice in glucose-averse German cockroaches, Blattella germanica}, volume={81}, journal={Journal of Insect Physiology}, author={Jensen, K. and Schal, C. and Silverman, J.}, year={2015}, pages={42–47} }
 @article{jensen_simpson_nielsen_hunt_raubenheimer_mayntz_2014, title={Nutrient-specific compensatory feeding in a mammalian carnivore, the mink, Neovison vison}, volume={112}, number={7}, journal={British Journal of Nutrition}, author={Jensen, K. and Simpson, S. J. and Nielsen, V. H. and Hunt, J. and Raubenheimer, D. and Mayntz, D.}, year={2014}, pages={1226–1233} }