Prof. Boris Krasnov

Born: 1955, Russia

Academic Qualifications:

Academic Positions:

Marco and Louise Mitrani Department of Desert Ecology (MDDE) - Professor

Research Interests:

Ecological Parasitology. Host-parasite relationships. Ectoparasites.Community ecology of desert animals (small mammals, ground-dwelling arthropods). Population and behavioral ecology of rodents.

Research Projects:

Physiological and behavioural aspects of host specificity in fleas. The dynamics and regulation mechanisms of ectoparasites in the Negev region. Density-dependent host (=habitat) selection in ectoparasites: Causal mechanisms and fitness consequences. Macroecology of host-parasite relationships.

Abstracts of Current Research:

Density-dependent host (=habitat) selection in ectoparasites: Causal mechanisms and fitness consequences: Application of isodar analysis to study of host selection in two flea species (Xenopsylla conformis and Xenopsylla ramesis) each parasitizing two rodents species (Meriones crassus and Gerbillus dasyurus) demonstrated that these fleas were able to perceive quantitative (amount of the resource; e.g. organic matter in the nest for flea larvae) and/or qualitative (pattern of resource acquisition; e.g. host defensiveness) differences between hosts. X. conformis appeared to be a density-dependent host selector that showed sharp selectivity at low density, whereas X. ramesis was density-independent host selector with a direct correspondence of density with host quality. The analysis, thus, suggested that ectoparasites, like other animals, behave as if they are able to make choices and decisions that favor environments in which their reproductive benefit is maximized. Isodar analysis of host preferences has led to testable hypotheses regarding mechanisms and consequences of host selection by fleas and, thus, justification of supposed fitness-density relations. We are studying these mechanisms and fitness consequences focusing on several hypotheses.
Between-host phylogenetic distance and mechanisms of host selection in haematophagous parasites: Physiological and behavioral aspects: Among host species that a parasite is able to exploit, a principle host and auxiliary hosts can be distinguished. The principal host is used by the majority of parasite individuals. This proposal addresses the question of parasite fitness in dependence of phylogenetic relatedness between hosts. The model system is represented by four species of fleas parasitic on mammals. We ask if fleas can distinguish between principle and auxiliary hosts and if parasite fitness, as measured by various feeding and reproductive parameters, is affected by a host species identity and its phylogenetic relatedness to the principal host species. Measurements of feeding efficiency and reproductive parameters will include estimates of bloodmeal size and digestion rate, metabolic costs of digestion, egg production, development rates and tolerance to starvation of the F1 generation. We predict that if a flea feeds on a principal host compared with an auxiliary host or on the auxiliary host phylogenetically closely-related versus distantly-related to the principal host, the flea will take larger bloodmeals, digest those meals more efficiently and as a result produce more and/or larger eggs. The F1 progeny will either be more abundant and/or have higher survivability as a result of hatching from larger eggs with more food provisions for the developing embryo. This study has broad applicability to the understanding of host selection in fleas and ectoparasites in general.
Acquired resistance, physiological costs and co-evolution of rodent-ectoparasite relationships: We propose to examine host specificity, immune response and acquired resistance of rodents to fleas. We hypothesize that the metabolic cost of acquired resistance and its effectiveness against the parasite is related to the degree of parasite host-specificity. The host-parasite system is represented by three flea species and three sympatric rodent species in the Negev desert, - Xenopsylla dipodilli, a specific flea of Gerbillus dasyurus, Parapulex chephrensis, a specific flea of Acomys cahirinus, and Nosopsyllus iranus theodori, a generalist flea which parasitizes both rodents. A third rodent Acomys russatus is usually not parasitized by fleas. We predict that specific flea-host relationships will have no or little development of acquired resistance. In contrast, rodents will expend more energy developing an effective resistance against non-specific fleas. Defense response of rodents will be induced by exposure to fleas as well as to injections by whole body extract of fleas. Measurements of acquired resistance to fleas will include feeding efficiency, fecundity and energy requirements. Examination of rodent blood will indicate the mechanisms of immunity stimulated by flea parasitism. Energy costs of acquired resistance to fleas will be estimated from maintenance budgets of rodents parasitized by specific and non-specific fleas.

Publications:

Krasnov, B.R., Fortuna, M., Mouillot, D., Khokhlova, I.S., Shenbrot, G.I. & Poulin, R.. Phylogenetic signal and species roles in compartmentalized mammal-flea netwroks. American Naturalist 179: 501-511 (2012)
Krasnov, B.R., Mouillot, D., Khokhlova, I.S., Shenbrot, G.I. & Poulin, R.. Compositional and phylogenetic dissimilarity of host communities drives compositional and phylogenetic dissimilarity of ectoparasite assemblages: geographic variation and scale-dependence. Parasitology 139: 338-347 (2012)
Arbiv, A., Khokhlova, I.S., Ovadia, O., Novoplansky, A. & Krasnov, B.R.. Use it or lose it: reproductive implications of experimental host shifting in a haematophagous ectoparasite. Journal of Evolutionary Biology 25: 1140-1147 (2012)
Raveh, A., Kotler, B.P., Abramsky, Z. & Krasnov, B.R. . Driven to distraction: Detecting the hidden costs of flea parasitism through foraging behaviour in gerbils. Ecology Letters 14: 47-51 (2011)
Krasnov, B.R., Stanko, M., Matthee, S., Laudisot, A., Leirs, H., Khokhlova, I.S., Korallo-Vinarskaya, N.P., Vinarski, M.V. & Morand, S. . Male hosts drive infracommunity structure of ectoparasites Oecologia 166: 1099-1010 (2011)
Krasnov, B.R., Poulin, R. & Mouillot, D.. Scale-dependence of phylogenetic signal in ecological traits of ectoparasites Ecography 34: 114-122 (2011)
Poulin, R., Krasnov, B.R. & Mouillot, D. . Host specificity in phylogenetic and geographic space Trends in Parasitology 27: 355-361 (2011)
Krasnov, B.R., Mouillot, D., Shenbrot, G.I., Khokhlova, I.S., Vinarski, M.V., Korallo-Vinarskaya, N.P. and Poulin, R. . Similarity in ectoparasite faunas of Palaearctic rodents as a function of host phylogenetic, geographic, or environmental distances: which matters the most? International Journal for Parasitology 40: 807-817 (2010)
Krasnov, B.R., Vinarski, M.V., Korallo-Vinarskaya, N.P., Mouillot, D. & Poulin, R. . Inferring associations among parasitic gamasid mites from census data. Oecologia 160: 175-185 (2009)
Morand, S. & Krasnov, B.R.. Why apply ecological laws to epidemiology? Trends in Parasitology 24: 304-309 (2008)
Krasnov, B. R., Stanko, M., Miklisova, D., Morand, S.. Distribution of fleas (Siphonaptera) among small mammals: mean abundance predicts prevalence via simple epidemiological model. International Journal for Parasitology 35: 1097-1101 (2005)
Krasnov, B. R., Khokhlova, I. S., Arakelyan, M. S. & Degen, A. A.. Is a starving host tastier? Reproduction in fleas parasitizing food limited rodents. Functional EcologyEcology 19: 625-631 (2005)
Krasnov, B. R., Mouillot, D., Shenbrot, G. I., Khokhlova, I. S. & Poulin, R.. Abundance patterns and coexistence processes in communities of fleas parasitic on small mammals. Ecography 28: 453-464 (2005)
Krasnov, B. R., Shenbrot, G. I., Khokhlova, I. S. & Poulin, R.. Diversification of ectoparasite assemblages and climate: an example with fleas parasitic on small mammals. Global Ecology and Biogeography 14: 167-175 (2005)
Krasnov, B. R., Poulin, R., Shenbrot, G. I., Mouillot, D. & Khokhlova, I. S.. Ectoparasitic ?jacks-of-all-trades?: relationship between abundance and host specificity in fleas (Siphonaptera) parasitic on small mammals. American Naturalist 164: 506-516 (2004)

Books:

Krasnov, B. R. , Functional and Evolutionary Ecology of Fleas: A Model for Ecological Parasitology, 593, Cambridge University Press, 2008
Shenbrot, G.I. & Krasnov, B. R. , An Atlas of the Geographic Distribution of the Arvicoline Rodents of the World (Rodentia, Muridae: Arvicolinae). , 336, Pensoft, 2005
Shenbrot, G.I., Krasnov, B.R. & Rogovin, K.A., Spatial Ecology of Desert Rodent Communities, 292, Springer, 1999

Book Chapters:

Krasnov, B.R. and Poulin, R., Ecological properties of a parasite: species-specific stability and geographical variation. , The biogeography of host-parasite interactions, S. Morand & B.R. Krasnov, 99-114, Oxford University Press, 2010

Edited Collections:

Morand, S. & Krasnov, B.R. , The Biogeography of Host-Parasite Interactions, Oxford University Press, 2010
Morand, S., Krasnov, B. R. & Poulin, R. , Micromammals and Macroparasites: From Evolutionary Ecology to Pest Management. , Springer, 2006
Krasnov, B. R. & Mazor, E. , The Makhteshim Country: Laboratory of Nature, Pensoft, 2001
Sokolov, V. E., Kotenkova, E. V. & Krasnov, B. R. , The House Mouse, Nauka, Moscow, 1989

Keywords:Host-parasite relationships, Ecology, Parasitology, Ectoparasites, Rodents, Behavior.

Links:	Personal Homepage

Phones:

Phone: 972-8-6596841
Fax: 972-8-6596772

Email:	krasnov@bgu.ac.il