Home About us Contact
|
Home About us Contact | ||
|
|
||
Flea Species Richness (flea + species_richness)
Selected AbstractsFlea species richness and parameters of host body, host geography and host ,milieu'JOURNAL OF ANIMAL ECOLOGY, Issue 6 2004BORIS R. KRASNOV Summary 1We have assessed how different host parameters affect species richness of flea assemblages using the independent contrasts method. Three groups of host parameters were examined. The first group included host body parameters (body size, basal and average daily metabolic rates), the second group included parameters of geographical range size and position of this range in relation to the equator (latitude) and the third group comprised parameters related to the number of sympatric closely related species. 2None of the host body parameters correlated with species richness of flea assemblages. 3Flea species richness increased with an increase in latitude of the geographical range centre of a host as well as with an increase in a composite variable that described the size of the geographical range. 4The number of sympatric closely related species both across the entire geographical range and locally was correlated positively with species richness of fleas. 5Our results show that species richness of ectoparasites is affected little by parameters of the host body and to a greater extent by parameters related to the host environment. [source] Prairie dog presence affects occurrence patterns of disease vectors on small mammalsECOGRAPHY, Issue 5 2008R. Jory Brinkerhoff Wildlife disease is recognized as a burgeoning threat to imperiled species and aspects of host and vector community ecology have been shown to have significant effects on disease dynamics. The black-tailed prairie dog is a species of conservation concern that is highly susceptible to plague, a flea-transmitted disease. Prairie dogs (Cynomys) alter the grassland communities in which they exist and have been shown to affect populations of small rodents, which are purported disease reservoirs. To explore potential ecological effects of black-tailed prairie dogs on plague dynamics, we quantified flea occurrence patterns on small mammals in the presence and absence of prairie dogs at 8 study areas across their geographic range. Small mammals sampled from prairie dog colonies showed significantly higher flea prevalence, flea abundance, and relative flea species richness than those sampled from off-colony sites. Successful plague transmission likely is dependent on high prevalence and abundance of fleas that can serve as competent vectors. Prairie dogs may therefore facilitate the maintenance of plague by increasing flea occurrence on potential plague reservoir species. Our data demonstrate the previously unreported ecological influence of prairie dogs on vector species assemblages, which could influence disease dynamics. [source] Relationship between host diversity and parasite diversity: flea assemblages on small mammalsJOURNAL OF BIOGEOGRAPHY, Issue 11 2004Boris R. Krasnov Abstract Aim, We examined the relationship between host species richness and parasite species richness using simultaneously collected data on small mammals (Insectivora, Rodentia and Lagomorpha) and their flea parasites. Location, The study used previously published data on small mammals and their fleas from 37 different regions. All the world's main geographical regions other than Australasia and Wallacea were represented in the study, i.e. neotropical, nearctic, palaearctic, oriental and afrotropical realms. Methods, We controlled the data for the area sampled and sampling effort and then tested this relationship using both cross-region conventional analysis and the independent contrasts method (to control for the effects of biogeographic historical relationships among different regions). Brooks parsimony analysis was used to construct a region cladogram based on the presence/absence of a host species and host phylogeny. Results, Both cross-region and independent contrasts analyses showed a positive correlation between host species richness and flea species richness. Conventional cross-region regression under- or overestimated fleas species richness in the majority of regions. Main conclusions, When the regression derived by the independent contrasts method was mapped onto the original tip data space, points that deviated significantly from the regression originated from Kenya, Mississippi and southern California (lower than expected flea richness) and Chile, Idaho, south-western California and Kyrgyzstan (higher than expected flea richness). These deviations can be explained by the environmental mediation of host,flea relationships and by a degree of environmental variety in sampled areas. [source] | ||||||||||