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Parasite Species Richness (parasite + species_richness)
Selected AbstractsDo threatened hosts have fewer parasites?JOURNAL OF ANIMAL ECOLOGY, Issue 2 2007A comparative study in primates Summary 1Parasites and infectious diseases have become a major concern in conservation biology, in part because they can trigger or accelerate species or population declines. Focusing on primates as a well-studied host clade, we tested whether the species richness and prevalence of parasites differed between threatened and non-threatened host species. 2We collated data on 386 species of parasites (including viruses, bacteria, protozoa, helminths and arthropods) reported to infect wild populations of 36 threatened and 81 non-threatened primate species. Analyses controlled for uneven sampling effort and host phylogeny. 3Results showed that total parasite species richness was lower among threatened primates, supporting the prediction that small, isolated host populations harbour fewer parasite species. This trend was consistent across three major parasite groups found in primates (helminths, protozoa and viruses). Counter to our predictions, patterns of parasite species richness were independent of parasite transmission mode and the degree of host specificity. 4We also examined the prevalence of selected parasite genera among primate sister-taxa that differed in their ranked threat categories, but found no significant differences in prevalence between threatened and non-threatened hosts. 5This study is the first to demonstrate differences in parasite richness relative to host threat status. Results indicate that human activities and host characteristics that increase the extinction risk of wild animal species may lead simultaneously to the loss of parasites. Lower average parasite richness in threatened host taxa also points to the need for a better understanding of the cascading effects of host biodiversity loss for affiliated parasite species. [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] Host intrinsic determinants and potential consequences of parasite infection in free-ranging red-fronted lemurs (Eulemur fulvus rufus)AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010Dagmar Clough Abstract Parasites and infectious diseases represent ecological forces shaping animal social evolution. Although empirical studies supporting this link abound in various vertebrate orders, both the study of the dynamics and impact of parasite infections and infectious diseases in strepsirrhine primates have received little empirical attention. We conducted a longitudinal parasitological study on four groups of wild red-fronted lemurs (Eulemur fulvus rufus) at Kirindy Forest, Madagascar, during two field seasons in consecutive years to investigate i) the degree of gastrointestinal parasite infection on population and individual levels and ii) factors potentially determining individual infection risk. Using a comprehensive dataset with multiple individually assignable parasite samples as well as information on age, sex, group size, social rank, and endocrine status (fecal androgen and glucocorticoid), we examined parasite infection patterns and host traits that may affect individual infection risk. In addition, we examined whether parasite infection affects mating and reproductive success. Our results indicated high variability in parasite infection on individual and population levels. Time of year and group size was important determinants of variability in parasite infection. Variation in hormone levels was also associated with parasite species richness and parasite infection intensity. Differences in parasite infection between years indicate a potential immune-enhancing function of steroid hormones on nematode infections, which has not been reported before from other vertebrates studied under natural conditions. Male mating and reproductive success were not correlated to any measure of parasite infection, which suggests a nonfunctional role of the parasites we examined in primate sexual selection. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc. [source] Gastrointestinal parasites of Howler monkeys (Alouatta palliata) inhabiting the fragmented landscape of the Santa Marta mountain range, Veracruz, MexicoAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2010Carolina Valdespino Abstract In recent years populations of howler monkeys (Alouatta palliata) in southeastern Mexico have decreased substantially due to the transformation and loss of natural habitats. This is especially evident in the Santa Marta mountain range, Veracruz, Mexico where several studies have evaluated the impact of fragmentation on howler monkey populations in order to propose management programs for their conservation. The conditions generated by fragmentation likely change the rates of parasitic infection and could decrease howler survival. In this study, gastrointestinal parasite species richness, prevalence, and egg density of infection were determined in howler groups inhabiting five forest fragments at the Santa Marta mountain range. Two hundred and seventy-eight fresh fecal samples were collected between October 2002 and April 2003. Three parasite species were found during the dry and the wet season in all forest fragments sampled: one unidentified species of Eimeriidae; Trypanoxyuris minutus (Oxyuridae); and Controrchis biliophilus (Dicrocoeliidae). Both the prevalence of T. minutus and infection density for all parasites differed between seasons and fragments (the largest fragment consistently differed from other fragments). Host density, distance to the nearest town, fragment size, fragment shape, and total basal area of food trees explained parasite prevalence, but each species had a different pattern. Although parasite richness was lower, prevalence and density were higher than values reported for howlers in conserved forests. These results suggest that the establishment of biological corridors and animal translocation programs must take into account the parasite ecology of each fragment to avoid higher infection rates and preclude potential consequent mortality. Am. J. Primatol. 72:539,548, 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||