IPBRG Investigators: Spence Behmer, Pierre Lesne, Carrie Deans, Richelle Marquess, Trevor Steele
Collaborators: Anthony Joern (KSU), Jason Karpac (TAMU), Hojun Song (TAMU),
Greg Sword (TAMU), Aaron Tarone (TAMU), Ed Vargo (TAMU),
Heiko Vogel (Max-Planck Institute of Chemical Ecology), Tony Zera (UNL)
Two key ideas drive this area of research. First, physiological mechanisms can provide unique insights into ecological patterns and processes. Second, animal behavior provides a window through which physiology can be viewed. Much of what we do under the remit of physiological ecology centers on nutritional physiology and the mechanisms associated with resource use, particulary macronutrients. Additionally, where possible, we use a comparative approach to gain insights into the evolution of physiological processes and mechanisms.
Knowing how insects use available resources provides the foundation for understanding a variety of issues, ranging from individual behavior up to population and community level processes. Much of our approach involves the ‘Geometric Framework‘ (GF), which emphasizes nutrient regulation and utilization. The GF is unique in that it allows for clear descriptions to be made of the foraging compromises and tradeoffs animals make when confronted with foods that vary nutritionally, contain defensive compounds, toxins, and/or are variously distributed in the environment. Using the GF give insights into both pre- and post-ingestive regulatory processes. Recently we have begun to use gene expression approaches, couched within the context of the GF, to explore more broadly how animals (mostly insects) respond to different nutrient inputs. Locusts, grasshoppers and caterpillars are our primary study organisms, but we also work on ants, crkicts, and Drosophila larvae.
We currently have two funded projects in the lab. The first is a USDA AFRI-BRAG collaborative project with Greg Sword. Here we are exploring how food macronutrient content affects susceptibility of Helicoverpa zea caterpillars to Bt transgenic crops. Our second is a Texas Invasive Ant Research grant that examines the nutritional physiology of the tawny crazy ant. We recently completed an NSF funded project (w/ Tony Zera) ivestigating the nutritonal correlates of life-history trade-offs in crickets.
Relevant Publications:
Deans, C.A., Behmer, S.T., Tessnow, A.E., Tamez-Guerra, P., Pusztai-Carey, M. and Sword, G.A.(2017) Nutrition affects insect susceptibility to Bt toxins. Scientific Reports 7, 39705. [pdf]
Clark, R.M., Zera, A.J. and Behmer, S.T. (2016) Metabolic rate is canalized in the face of variable life history and nutritional environment. Functional Ecology 30, 922-931. [pdf]
Deans, C.A., Behmer, S.T., Fiene, J. and Sword, G.A. (2016) Spatio-temporal, genotypic, and environmental effects on plant soluble protein and digestible carbohydrate content:
implications for insect herbivores with cotton as an exemplar. Journal of Chemical Ecology, 42, 1151-1163. [pdf]
Deans, C.A., Sword, GA and Behmer, S.T. (2016) Nutrition as a neglected factor in insect herbivore susceptibility to Bt toxins. Current Opinion in Insect Science 15, 97-103. [pdf)]
Zera, A.J., Clark, R.M. and Behmer, S.T. (2016) Lipogenesis in a wing-polymorphic cricket: Canalization versus morph-specific plasticity as a function of nutritional heterogeneity. Journal of Insect Physiology 95, 118-132. [pdf]
Cook, S.C., Eubanks, M.D., Gold, R.E. and Behmer, S.T. (2016) Summer and fall ants havedifferent physiological responses to food macronutrient content. Journal of Insect Physiology 87, 35-44. [pdf]
Behmer, S.T. (2016) Virtual Issue: Nutritional Ecology. Journal of Animal Ecology.
Deans, Carrrie A., Sword, G.A. and Behmer, S.T. (2015) Revisiting macronutrient regulation in the polyphagous herbivore Helicoverpa zea (Lepidoptera: Noctuidae): New insights via nutritional geometry. Journal of Insect Physiology 81, 21-27. [pdf]
Lenhart, P.A., Eubanks, M.D., and Behmer, S.T. (2015) Water stress in grasslands: dynamic responses of plants and insect herbivores. Oikos 128, 381-390. [pdf]
Clark, R.M., Zera, A.J. and Behmer, S.T. (2015) Nutritional physiology of life-history trade-offs: how food protein-carbohydrate content influences life-history traits in the wing-polymorphic cricket Gryllus firmus. The Journal of Experimental Biology 218, 298-308. [pdf]
Deans, C.A., Behmer, S.T., Kay, A. and Voelz, N. (2015) The influence of enrichment and dissolved N:P ratios on mayfly (Baetis spp.) growth in high-nutrient detritus-based streams. Hydrobiologia 742, 298-308. [pdf]
Roeder, K.A. and Behmer, S.T. (2014) Lifetime consequences of food protein-carbohydrate content for an insect herbivore. Functional Ecology 28, 1135-1143. [pdf]
Le Gall, M. and Behmer, S.T. (2014) Effects of protein and carbohydrate on an insect herbivore: the vista from a fitness landscape. Integrative and Comparative Biology 54, 1135-1143. [pdf]
Clark, R.M., McConnell, A., Zera, A.J., and Behmer, S.T. (2013) Nutrient regulation strategies differ between cricket morphs that trade-off dispersal and reproduction.
Functional Ecology 27, 1126-1133. [pdf]
Joern, A., Provin, T. and Behmer, S.T. (2012) Not just the usual suspects: Insect herbivore
populations and communities are associated with multiple plant nutrients.
Ecology 93, 1002-1015. [pdf]
Behmer, S.T. and Joern, A. (2012) Insect herbivores viewed through a physiological
framework: insights from Orthoptera. In Insect Outbreaks Revisited (eds. P. Barbosa,
D.K. Letourneau and A.A. Agrawal), pp 3-29. Wiley-Blackwell, Chichester, U.K. [pdf]
Cook, S.C., Wynalda, R.A., Gold, R.E., and Behmer, S.T. (2012) Macronutrient regulation in the Rasberry crazy ant (Nylanderia sp. nr. pubens). Insect Sociaux 59, 93-100. [pdf]
Cook, S.C., Eubanks, M.D., Gold, R.E., and Behmer, S.T. (2011) Seasonality directs contrasting food collection behavior and nutrient regulation strategies of an insect society.
PLoS ONE 6, e25407. [pdf]
Goeriz Pearson, R.E., Behmer, S.T., Gruner, D.S., and Denno, R.F. (2011) Effects of diet quality on performance and nutrient regulation in an omnivorous katydid. Ecological Entomology 36, 471-479. [pdf]
Chi, Y.H., Jing, X., Lei, J., Ahn, J-E., Koo, Y.D., Yun, D-J., Lee, S.Y., Behmer, S.T.,
Koiwa, H., and Zhu-Salzman, K. (2011) Stability of AtVSP in the insect digestive
canal determines its definsive capability. Journal of Insect Physiology
57, 391-399. [pdf]
Cook, S.C., Eubanks, M.D., Gold, R.E., and Behmer, S.T. (2010) Colony-level nutrient
regulation in ants: mechanisms, hoarding and associated costs. Animal
Behaviour. 79, 429-437. [pdf]
Cook, S.C. and Behmer, S.T. (2010) Macronutrient regulation in the tropical terrestrial ant,
Ectatomma ruidum (Formicidae): a field study. Biotropica. 42, 135-139. [pdf]
Behmer, S.T. (2009) Insect herbivore nutrient regulation. Annual Review of
Entomology 54, 165-187. (click here for a free pdf)
Behmer, S.T. (2009) Animal behaviour: feeding the superorganism. Current Biology 19,
R366-R368. [pdf]
Warbrick-Smith, J., Simpson, S.J. Raubenheimer, D. and Behmer, S.T. (2009). Three hundred and fifty generations of extreme food specialization: testing a prediction of nutritional ecology. Entomologia Experimentalis et Applicata 132, 65-75. [pdf]
Behmer, S.T. and Joern, A. (2008) Coexisting generalist herbivores occupy unique
nutritional feeding niches. Proceedings of the National Academy of Sciences,
USA 105, 1977-1982. [pdf]
Boswell, A.W., Provin, T. and Behmer, S.T. (2008) The relationship between body mass and elemental composition in nymphs of the grasshopper Schistocerca americana. Journal
of Orthoptra Research 17, 1-7. [pdf]
Warbrick-Smith, J., Behmer, S.T., Lee, K.P., Raubenheimer, D. and Simpson, S.J. (2006)
Evolving resistance to obesity in an insect. Proceedings of the National Academy of
Sciences, USA 103, 14045-14049. [pdf]
Lee, K.W., Behmer, S.T. and Simpson, S.J. (2006) Nutrient regulation in relation to diet
breadth: a comparison of Heliothis sister species and a hybrid. The Journal of Experimental Biology 209, 2076-2084. [pdf]
Behmer, S.T., Lloyd, C.M., Raubenheimer, D., Stewart-Clark, J., Knight, J., Leighton, R.S.,
Harris, F.A. and Smith, J.A.C. (2005) Metal hyperaccumulation in plants: mechanisms of
defence against insect herbivores. Functional Ecology 19, 55-66. [pdf]
Simpson, S.J., Sibly, R.M., Lee, K., Behmer, S.T. and Raubenheimer, D. (2004) Optimal foraging with multiple nutrient requirements. Animal Behaviour 68, 1299-1311. [pdf]
Opstad, R., Rogers, S.M., Behmer, S.T. and Simpson, S.J. (2004) Behavioural correlates
of phenotypic plasticity in mouthpart chemoreceptor numbers in locusts. Journal of
Insect Physiology 50, 725-736. [pdf]
Behmer, S.T., Raubenheimer, D. and Simpson, S.J. (2003) The effects of distance between
foods on nutrient regulation in a highly mobile insect herbivore.
Animal Behaviour 66, 665-675. [pdf]
Lee, K.P., Raubenheimer, D, Behmer, S.T. and Simpson, S.J. (2003) A correlation between
macronutrient balancing and insect host-plant range: evidence from the specialist caterpillar Spodoptera exempta (Walker). Journal of Insect Physiology 49, 1161-1171. [pdf]
Behmer, S.T., Simpson, S.J. and Raubenheimer, D. (2002) Herbivore foraging in chemically heterogeneous environments: nutrients and secondary metabolites.
Ecology 83, 2489-2501. [pdf]
van der Zee, B., Behmer, S.T. and Simpson, S.J. (2002) Food mixing strategies in the
desert locust:effects of phase, distance between foods and food nutrient content.
Entomologia Experimentalis et Applicata 103, 227-237. [pdf]
Lee, K.W., Behmer, S.T., Raubenheimer, D. and Simpson, S.J. (2002) A geometric analysis of nutrient regulation in the generalist caterpillar Spodoptera littoralis (Boisduval). Journal of Insect Physiology 48, 655-665. [pdf]
Simpson, S.J., Raubenheimer, D., Behmer, S.T., Whitworth, A. and Wright, G.A. (2002)
A comparison of nutritional regulation in solitarious and gregarious phase nymphs
of the desert locust, Schistocerca gregaria. The Journal of Experimental Biology 205,
121-129. [pdf]
Behmer, S.T., Raubenheimer, D. and Simpson, S.J. (2001) Frequency-dependent food
selection in locusts:a geometric analysis of the role of nutrient balancing. Animal
Behaviour 61, 995-1005. [pdf]
Frazier, M.R., Harrison, J.F. and Behmer, S.T. (2000) Effects of diet on titratable acid-base
excretion in grasshoppers. Physiological and Biochemical Zoology 73, 66-76. [pdf]
Joern, A. and Behmer, S.T. (1998) Impact of diet quality on demographic attributes in adult grasshoppers and the nitrogen limitation hypothesis. Ecological Entomology 23,
174-184. [pdf]
Joern, A. and Behmer, S.T. (1997) Importance of dietary nitrogen and carbohydrates to survival, growth and reproduction in adults of the grasshopper Ageneotettix deorum
(Orthoptera: Acrididae). Oecologia 112, 201-208. [pdf]
Chambers, P., Sword, G., Angel, J., Behmer, S. and Bernays, E.A. (1996) Foraging by
generalist grasshoppers: dietary mixing and the role of crypsis.
Animal Behaviour 52, 155-165. [pdf]
Behmer, S. and Joern, A. (1994) The influence of proline on diet selection: sex-specific feeding preferences by the grasshoppers Ageneotettix deorum and Phoetaliotes nebrascensis (Orthoptera: Acrididae). Oecologia 98, 76-82. [pdf]
Behmer, S. and Joern, A. (1993) Diet choice by a grass-feeding grasshopper based on the need for a limiting nutrient. Functional Ecology 7, 522-527. [pdf]