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1.
Assembly rules for New England ant assemblages   总被引:10,自引:0,他引:10  
Community assembly rules specify patterns of species co-occurrence and morphology dictated by interspecific competition. We collected data on the occurrence of ground-foraging ant species in 22 ombrotrophic bogs and adjacent forest plots of New England to test two general assembly rules: reduced co-occurrence of species among communities, and even spacing of body sizes of species within communities. We used null models to generate random communities unstructured by competition and evaluated patterns at regional and local spatial scales. At the regional scale, species co-occurrence in forests, but not bogs, was less than expected by chance, whereas, at the local scale, co-occurrence in both habitats was not different from random. At the regional scale, spacing of body size distributions was random (in bogs) or aggregated (in forests). At the local scale, body size patterns were weakly segregated in bogs, but random or weakly aggregated in forests. In bogs, size ratio constancy was accompanied by greater generic diversity than expected. Although assembly rules were originally developed for vertebrate communities, they successfully explained some patterns in New England ant assemblages. However, the patterns were contingent on spatial scale, and were distinctly different for bog and forest communities, despite their close proximity and the presence of many shared species in both assemblages. The harsh physical conditions of bogs may act as a habitat filter that alters community assembly rules.  相似文献   

2.
Xavier Arnan  Alan N. Andersen  Heloise Gibb  Catherine L. Parr  Nathan J. Sanders  Robert R. Dunn  Elena Angulo  Fabricio B. Baccaro  Tom R. Bishop  Raphaël Boulay  Cristina Castracani  Xim Cerdá  Israel Del Toro  Thibaut Delsinne  David A. Donoso  Emilie K. Elten  Tom M. Fayle  Matthew C. Fitzpatrick  Crisanto Gómez  Donato A. Grasso  Blair F. Grossman  Benoit Guénard  Nihara Gunawardene  Brian Heterick  Benjamin D. Hoffmann  Milan Janda  Clinton N. Jenkins  Petr Klimes  Lori Lach  Thomas Laeger  Maurice Leponce  Andrea Lucky  Jonathan Majer  Sean Menke  Dirk Mezger  Alessandra Mori  Jimmy Moses  Thinandavha Caswell Munyai  Omid Paknia  Martin Pfeiffer  Stacy M. Philpott  Jorge L.P. Souza  Melanie Tista  Heraldo L. Vasconcelos  Javier Retana 《Global Change Biology》2018,24(10):4614-4625
The relationship between levels of dominance and species richness is highly contentious, especially in ant communities. The dominance‐impoverishment rule states that high levels of dominance only occur in species‐poor communities, but there appear to be many cases of high levels of dominance in highly diverse communities. The extent to which dominant species limit local richness through competitive exclusion remains unclear, but such exclusion appears more apparent for non‐native rather than native dominant species. Here we perform the first global analysis of the relationship between behavioral dominance and species richness. We used data from 1,293 local assemblages of ground‐dwelling ants distributed across five continents to document the generality of the dominance‐impoverishment rule, and to identify the biotic and abiotic conditions under which it does and does not apply. We found that the behavioral dominance–diversity relationship varies greatly, and depends on whether dominant species are native or non‐native, whether dominance is considered as occurrence or relative abundance, and on variation in mean annual temperature. There were declines in diversity with increasing dominance in invaded communities, but diversity increased with increasing dominance in native communities. These patterns occur along the global temperature gradient. However, positive and negative relationships are strongest in the hottest sites. We also found that climate regulates the degree of behavioral dominance, but differently from how it shapes species richness. Our findings imply that, despite strong competitive interactions among ants, competitive exclusion is not a major driver of local richness in native ant communities. Although the dominance‐impoverishment rule applies to invaded communities, we propose an alternative dominance‐diversification rule for native communities.  相似文献   

3.
Epiphytes are conspicuous structural elements of tropical forest canopies. Individual tree crowns in lowland forests may support more than 30 ant species, yet we know little about the effects of epiphytes on ant diversity. We examined the composition of arboreal ant communities on Annona glabra trees and their interactions with the epiphytic orchid Caularthron bilamellatum in Panama. We surveyed the ants on 73 trees (45 with C. bilamellatum and 28 lacking epiphytes) and recorded their nest sites and behavioral dominance at baits. We found a total of 49 ant species (in 20 genera), ranging 1–9 species per tree. Trees with C. bilamellatum had higher average (±SD) ant species richness (4.2±2.28) than trees without epiphytes (2.7±1.21). Hollow pseudobulbs (PBs) of C. bilamellatum were used as nest sites by 32 ant species, but only 43 percent of suitable PBs were occupied. Ant species richness increased with PB abundance in trees, but nest sites did not appear to be a limiting resource on A. glabra. We detected no close association between ants and the orchid. We conclude that higher ant species richness in the presence of the orchid is due to bottom‐up effects, especially the year‐round supply of extrafloral nectar. The structure of ant communities on A. glabra partly reflects interference competition among behaviorally dominant species and stochastic factors, as observed in other forests.  相似文献   

4.
1. Interspecific competition is a major structuring principle in ecological communities. Despite their prevalence, the outcome of competitive interactions is hard to predict, highly context-dependent, and multiple factors can modulate such interactions. 2. We tested predictions concerning how competitive interactions are modified by anthropogenic habitat disturbance in ground-foraging ant assemblages inhabiting fragmented Inter-Andean tropical dry forests in southwestern Colombia, and investigated ant assemblages recruiting to baits in 10 forest fragments exposed to varying level of human disturbance. 3. Specifically, we evaluated how different components of competitive interactions (patterns of species co-occurrence, resource partitioning, numerical dominance, and interspecific trade-offs between discovery and dominance competition) varied with level of habitat disturbance in a human-dominated ecosystem. 4. Multiple lines of evidence suggest that the role of competitive interactions in structuring ground-foraging ant communities at baits varied with respect to habitat disturbance. As disturbance increased, community structure was more likely to exhibit random co-occurrence patterns, higher levels of monopolization of food resources by dominant ants, and disproportionate dominance of a single species, the little fire ant (Wasmannia auropunctata). At a regional scale, we found evidence for a trade-off between dominance and discovery abilities of the 15 most common species at baits. 5. Together, these results suggest that human disturbance modifies the outcome of competitive interactions in ground-foraging ant assemblages and may promote dominant species that reduce diversity and coexistence in tropical ecosystems.  相似文献   

5.
A theoretical dichotomy in community ecology distinguishes between mechanisms that stabilize species coexistence and those that cause neutral drift. Stable coexistence is predicted to occur in communities where competing species have niche-partitioning mechanisms that reduce interspecific competition. Neutral communities are predicted to be structured by stochastic processes that are not influenced by species identity, but that may be influenced by priority effects and dispersal limitation. Recent developments have suggested that neutral interactions may be more common at local scales, while niche structuring may be more common at larger scales. We tested for mechanisms that could promote either stable coexistence or neutral drift in a bromeliad-dwelling mosquito community by evaluating A) if a hypothesized within-bromeliad niche partitioning mechanism occurs in the community, B) if this mechanism correlates with local species co-occurrence patterns, and C) if patterns of coexistence at the larger (metacommunity) scale were consistent with those at the local scale. We found that mosquitoes in this community do partition space within containers, and that species with the strongest potential for competition co-occurred least. Species with overlapping spatial niches minimized co-occurrence by specialising in bromeliads of differing sizes, effectively changing the scale at which they coexist. In contrast, we found no evidence to support neutral dynamics in mosquito communities at either scale. In this community, a niche-based mechanism that is predicted to stabilize species coexistence explains co-occurrence patterns within and among bromeliads.  相似文献   

6.
Abstract.  1. In insect communities on fermented tree sap, agonistic interactions occur frequently among the component species. This study examined the effects of such interference competition on community structure and species co-occurrence on a spatio-temporally small scale.
2. Experimental removal of giant hornets ( Vespa mandarinia ), one of the most dominant species, showed no effect on either species richness or total abundance of the remaining insects. Significant increases in abundance were detected for five out of 19 taxa: V. ducalis , V. crabro , Lasius japonicus , Cryptarcha lewisi , and a group of micro sap beetles ( Epuraea spp., Haptoncus spp., and Haptoncurina spp.).
3. Behavioural observations indicated that interference did not alter the staying time at a patch (an exuding spot on a tree) for V. mandarinia , Rhomborrhina japonica , and Neope goschkevitschii . Interference-mediated departure from a patch was less frequent than departure without interference for all nine species observed, except for R. japonica . These behavioural contexts varied yearly for several species.
4. These results suggest that interference competition is a minor determinant of overall community structure, despite its conspicuousness. This weak effect of interference may be attributed to the short stay of dominant species and to individual behavioural responses, such as competitor avoidance. The variable influence of interference might be related to differences in species attributes, such as dominance hierarchies.  相似文献   

7.
Body mass has been considered one of the most critical organismal traits, and its role in many ecological processes has been widely studied. In hummingbirds, body mass has been linked to ecological features such as foraging performance, metabolic rates, and cost of flying, among others. We used an evolutionary approach to test whether body mass is a good predictor of two of the main ecological features of hummingbirds: their abundances and behavioral dominance. To determine whether a species was abundant and/or behaviorally dominant, we used information from the literature on 249 hummingbird species. For abundance, we classified a species as “plentiful” if it was described as the most abundant species in at least part of its geographic distribution, while we deemed a species to be “behaviorally dominant” when it was described as pugnacious (notably aggressive). We found that plentiful hummingbird species had intermediate body masses and were more phylogenetically related to each other than expected by chance. Conversely, behaviorally dominant species tended to have larger body masses and showed a random pattern of distribution in the phylogeny. Additionally, small‐bodied hummingbird species were not considered plentiful by our definition and did not exhibit behavioral dominance. These results suggest a link between body mass, abundance, and behavioral dominance in hummingbirds. Our findings indicate the existence of a body mass range associated with the capacity of hummingbird species to be plentiful, behaviorally dominant, or to show both traits. The mechanisms behind these relationships are still unclear; however, our results provide support for the hypothesis that body mass is a supertrait that explains abundance and behavioral dominance in hummingbirds.  相似文献   

8.
Numerous studies have addressed variation in the local occurrence and abundance of species, but only recently have investigators begun considering the influence of spatial context on community structure. We examined the influence of geographic position within a species’ range on its dominance (relative abundance) within the community. Our three primary questions were: 1) Does dominance within a community vary across a species’ range? 2) Do dominance‐location trends differ between widely and narrowly distributed species? and 3) Does dominance within a guild vary across a species range? We examined 40 passerine species (20 widely distributed, 20 narrowly distributed) and their communities using North American Breeding Bird Survey data, of which, a subset of 11 species belonging to a single foraging guild were used for addressing guild effects. Data were gathered from communities at the center (10 locations) and periphery (10 locations) of each species’ range. Focal species were significantly less dominant at locations on the periphery of their ranges compared to central locations, and did not differ between widely and narrowly distributed species. In examining factors influencing these patterns, it was found that narrowly distributed species occur in communities of fewer individuals and fewer species compared to widely distributed species irrespective of locale. Within the foraging guild, dominance was also lower at the periphery than at the center of focal species’ ranges. However, guild abundance was also lower at the periphery of ranges while guild richness did not vary with locale. Specifically, focal species abundance decreased at a greater rate than abundance of other members of the foraging guild. Contrary to overall community data, widely distributed species were more dominant members of their guild at the center of their ranges. No significant patterns were found between distribution and guild dominance at the periphery of ranges.  相似文献   

9.
Abstract: Staging areas and migratory stopovers of wetland birds have the potential to function as geographic bottlenecks; entire populations within a flyway may be affected by the quality and quantity of available wetland habitat at stopover sites. Although approximately 90% of playa wetlands in the Rainwater Basin (RWB) region of south-central Nebraska, USA, have been destroyed, the area still provides essential stopover habitat for >10 million waterfowl each spring. We evaluated community patterns and species associations to assess importance of assembly rules in structuring wetland bird communities during migration and to better facilitate multispecies conservation and management strategies. We surveyed 36–40 playas twice weekly in the RWB and observed approximately 2.6 million individual migratory wetland birds representing 72 species during 3 spring migrations 2002–2004. We evaluated spatial and temporal species co-occurrence patterns of geese, dabbling ducks, diving ducks, and shorebirds using null model analysis. Goose species co-occurrence scores did not differ from random in any year of the study, suggesting that goose species frequently use the same habitats during migration. Co-occurrence patterns among dabbling ducks were not different than expected by chance in any year; however, when we evaluated co-occurrence at a weekly scale, dabbling ducks co-occurred less often than expected during weeks of peak migration (high abundance), indicating that dabbling duck species spatially segregated at high densities. Diving duck co-occurrence patterns did not differ from random in any year, suggesting that diving duck species used the same habitats during migration. Shorebird species co-occurred less often than expected in 2002 and 2004, and during weeks of high shorebird abundance, indicating that shorebird communities were distinctly structured during those times. Most association values among lesser snow geese (Chen caerulescens) and dabbling duck species were positive, indicating dabbling ducks did not avoid wetlands with snow geese, a concern for waterfowl managers. However, we frequently observed snow geese and dabbling ducks using different microhabitats within a wetland, which indicate species associations and co-occurrence patterns may have occurred at a finer spatial scale than we measured. This approach of co-occurrence analysis will allow wildlife managers charged with multispecies management at migration stopover sites to make informed conservation and management decisions based on community structure rather than historic single-species approaches.  相似文献   

10.
Factors that determine the relative abundance of bumblebee species remain poorly understood, rendering management of rare and declining species difficult. Studies of bumblebee communities in the Americas suggest that there are strong competitive interactions between species with similar length tongues, and that this competition determines the relative abundance of species. In contrast, in Europe it is common to observe several short-tongued species coexisting with little or no evidence for competition shaping community structure. In this study we examine patterns of abundance and distribution in one of the most diverse bumblebee communities in Europe, found in the mountains of southern Poland. We quantify forage use when collecting nectar and pollen for 23 bumblebee species, and examine patterns of co-occurrence and niche overlap to determine whether there is evidence for inter-specific competition. We also test whether rarity can be explained by diet breadth. Up to 16 species were found coexisting within single sites, with species richness peaking in mountain pasture at ~1,000 m altitude. Results concur with previous studies indicating that the majority of pollen collected by bumblebees is from Fabaceae, but that some bee species (e.g. B. ruderatus) are much more heavily dependent on Fabaceae than others (e.g. B. lucorum). Those species that forage primarily on Fabaceae tended to have long tongues. In common with studies in the UK, diet breadth was correlated with abundance: rarer species tended to visit fewer flower species, after correcting for differences in sample size. No evidence was found for similarity in tongue length or dietary overlap influencing the likelihood of co-occurrence of species. However, the most abundant species (which co-occurred at most sites) occupied distinct dietary niche space. While species with tongues of similar length tended, overall, to have higher dietary niche overlap, among the group of abundant short-tongued species that commonly co-occurred there was marked dietary differentiation which may explain their coexistence.  相似文献   

11.
Aim To test the hypothesis that communities with higher diversity have more predictable properties by examining patterns of community structure along a species richness gradient. Location Trinidad and Tobago (11°00 N, 61°00 W), on the South American continental shelf, opposite the Orinoco River delta, north‐east Venezuela. Methods We used quantile regressions to investigate how three total abundance, absolute and relative dominance measures – numerical abundance, biomass and energy use, respectively – change across a species richness gradient. We investigated which allocation rule best mimics community assembly in this species richness gradient by examining the abundance of the dominant species and comparing it with predictions of niche apportionment models. Results All measures of total abundance increase on average across the gradient, but the upper limit remains constant. On average, absolute dominance is constant, but the distance between the upper and lower limits decreases along the gradient. Relative dominance decreases with species richness. Observed dominance patterns are best described by Tokeshi's random fraction model. Main conclusions Our results show that both total abundance and absolute dominance become increasingly variable as biodiversity decreases. Consequently, our study suggests that ecosystem properties are less predictable when biodiversity is lower.  相似文献   

12.
Predictable patterns of species number have been observed in relation to habitat size, habitat heterogeneity and environmental conditions, while patterns in relative abundance of species have been examined for few communities and no assembly rules have been established. We studied communities of attached macroalgae in 61 individual sites located in four different areas; the inner, middle and outer parts of three neighbouring low-tidal estuaries and the adjacent open waters of the Kattegat, Denmark. The objectives were to determine (1) the relationships of species number and rank-abundance to the environmental conditions, and (2) the importance of scale and the consistency of species rank number at the sites for these relationships. We found that species number increased significantly from the inner estuaries to the open coastal waters along with decreasing nutrient concentrations. Turnover (β) diversity was lowest in the open waters suggesting that species composition was more similar among samples there than in the estuaries. Rank-abundance curves did not differ between depth intervals and individual sites across the environmental gradients. However, the summed rank-abundance patterns for two sites showed significantly steeper initial slopes and dominance of few species (i.e., low evenness) in the inner estuaries than in open waters. This pattern was due to high rank consistency of dominant species among sites in the inner estuaries. In open waters rank consistency was low, and the summed abundance across sites showed an even abundance of species. The results imply that the scale of the study and the community variability observed at that particular scale, is the main determinant of abundance patterns.  相似文献   

13.
In 2005, the non-native Nylanderia flavipes was first recorded from Ohio. Here, we present the results of a baseline study designed to assess the status of this exotic species in northeastern Ohio and to explore its potential impacts on local ant communities and the extent to which it has been incorporated into the diet of a native predator, the red-backed salamander. At the sites where N. flavipes occurred, we found a sixfold increase in total ant abundance, with 87% of all ants collected being N. flavipes. The high numerical dominance of N. flavipes did not lead to observable changes in the species richness and abundance of the native ant community. At baits, N. flavipes did not engage in interspecific combat and did not exhibit aggression towards native ants. Thus, aggression and interference competition are not likely factors explaining the high local abundance of N. flavipes. Red-backed salamanders have incorporated N. flavipes into their diet, but further research is needed to understand the interactions of N. flavipes within the forest-floor food web. Although we did not detect changes in the local ant communities in the presence of N. flavipes, we argue that this species’ high local abundance and ability to forage at cooler temperatures may give it a competitive advantage and thereby affect native ants through exploitative competition.  相似文献   

14.
The role of competition in structuring communities of herbivorous insects is still debated. Despite this, few studies have simultaneously investigated the strength of various forms of competition and their effect on community composition. In this study, we examine the extent to which different types of competition will affect the presence and abundance of individual leaf miner species in local communities on oak trees Quercus robur. We first use a laboratory experiment to quantify the strength of intra‐ and interspecific competition. We then conduct a large‐scale field experiment to determine whether competition occurring in one year extends to the next. Finally, we use observational field data to examine the extent to which mechanisms of competition uncovered in the two experiments actually reflect into patterns of co‐occurrence in nature. In our experiment, we found direct competition at the leaf‐level to be stronger among conspecific than among heterospecific individuals. Indirect competition among conspecifics lowered the survival and weight of larvae of T. ekebladella, both at the branch and the tree‐level. In contrast, indirect competition among heterospecifics was only detected in one out of three species pairs examined. In the field experiment, the presence of a given moth species in one year affected the relative abundance of leaf miner species in the next year. Nevertheless, patterns of competition observed in these experiments did not translate into repulsion among free‐ranging leaf miners: conspecific larvae of four leaf‐mining species were aggregated on the same trees, shoots and leaves. In contrast, heterospecific larvae were only aggregated at the tree‐level. We propose that despite the fact that leaf miners do compete and that such effects extend through time, the incidence and strength of competition is relatively small at realistic densities. Hence, competition will likely be of minor importance in shaping the distribution of leaf miners in a natural setting.  相似文献   

15.
Competition effects on community development are difficult to quantify in species-rich plant communities due to the complexity of possible interactions. We used multispecies mixtures to investigate how species identity and competitive interactions influence the development of plant communities. Given the same set of species with differing initial abundance in various communities, we tested whether communities would become more similar (converge) or dissimilar (diverge) over time depending on the relative importance of species identity and competition. Twenty-four experimental communities were established by planting seedlings of twelve wetland species at different relative abundances and absolute densities. The development of the communities was monitored over three years, and yearly changes in biomass were modelled as a linear function of the species biomass at the start of each period. After three years, a clear dominance structure had developed, with four species making up 80% of the aboveground biomass. In all three years, community dynamics was driven by differences in relative growth rates among the species (i.e. an effect of species identity). However, in the second and third years negative density dependence was also important, with changes in the relative abundance of the most abundant species being negatively related to their biomass at the start of the period. Multiple species interactions – though generally weaker than effects of species identity and intraspecific competition – became increasingly important and also contributed to the dominance pattern. It is concluded that species identity and negative density dependence of the dominant species were the most important factors causing the experimental plant communities to converge. We suggest that model systems composed of several species offer a useful method for investigating the influence of functional traits upon community dynamics.  相似文献   

16.
Reeve et al. (2016, Ecography, 39 , 990‐997) found that ecologically flexible endemics dominate Indo‐Pacific bird communities. This negative relationship between local abundance and global range size contrasts strongly with the positive range size‐abundance relationship “rule,” which would predict community dominance by globally widespread species. Theuerkauf et al. (2017, Journal of Biogeography, 44 , 2161–2163) provide new data from New Caledonia which they claim invalidate our study. They find positive relationships between local abundance and local range size, which they attribute to endemic species having narrower habitat niches than globally widespread species. We reanalysed their data using global range sizes, corroborating the pattern we originally reported: negative relationships between local abundance and global range size, driven by a subset of adaptable endemic species. We stress the importance of being explicit about the scale of ecological mechanisms, and ensuring that the scale of analysis matches the scale of interpretation.  相似文献   

17.
《植物生态学报》2017,41(12):1219
Aims Interspecific associations can reflect how species are assembled into communities. The objectives of this study were to examine the patterns of woody species co-occurrence and to determine how species’ abundance would affect species associations. Methods Data from a total of 23 plots were used to test the interspecific associations of 93 woody plant species in forest communities of Putuoshan Island in Zhejiang Province. We compared the observed species associations with the expected patterns at random, and correlated interspecific association intensities with co-dominance propensity of species pairs. Important findings Species distribution co-varied among plots at the spatial scale of either 10 m × 10 m or 20 m × 20 m, but the majority of the 4 278 species pairs were not significantly associated. Interspecific association intensities were positively correlated with co-dominance propensity of species pairs, indicating that species abundance is a key factor affecting the interspecific co-occurrence. The observed values of variance ratio and the proportion of significantly associated species pairs consistently fell outside of the 2.5th-97.5th percentiles of random expectations (i.e. randomly permuting species across plots), suggesting that deterministic processes also play a role in species associations on the Putuoshan Island. We conclude that the pattern of woody species co-occurrence on Putuoshan Island are structured by both niche and stochastic processes.  相似文献   

18.
Using a large body of observational data on the occurrence ofSorex shrews in boreal forests, we test two models that predict the structure of small mammal communities along a gradient of increasing habitat productivity. Tilman’s (1982) model predicts a humped curve of species richness along productivity gradients. In contrast, we found a linear increase in species richness with increasing logarithm of the pooled density of shrews, which we use as a measure of habitat productivity for shrews. The model of Hanski and Kaikusalo (1989) assumes a trade-off between exploitative and interference competitive abilities, and it predicts that the size structure of small mammal communities should shift from the dominance of small species (superior in exploitative competition) in unproductive habitats to the dominance of large species (superior in interference competition) in productive habitats. Shrew assemblages show such a shift. Though it is not possible to draw definite conclusions about the role of interspecific competition from our observational data, the changing size structure of local shrew assemblages with increasing habitat productivity is a predictable feature of their community structure.  相似文献   

19.
Scaling biodiversity patterns has been recognized lately as a very important issue in the search of global processes; however coexistence and assemblage patterns are typically approached at a single spatial scale. Here, we examined coexistence and co-occurrence patterns of desert small mammal communities across different spatial scales in the search of general community patterns. We sampled small mammals in Monte desert (Argentina, South America) for small spatial scales and reviewed published papers from other worldwide deserts for large spatial scale analyses. We used classic community estimators (Shannon, Richness), rank abundance curves and fitting distributions to analyze species coexistence and co-occurrence patterns. Assemblage patterns were analyzed evaluating nestedness across spatial scales and among deserts. Worldwide desert small mammal assemblages are characterized mainly by low species richness and high variation in species composition. The central Monte desert of Argentina showed a consistent assemblage pattern across spatial scales, with a generalist species being the most abundant and widely distributed, accompanied by other subordinate and more narrowly distributed species. All Monte desert communities were significantly nested, with nestedness increasing with scale from patch to regional. Assemblage and coexistence patterns were similar when comparing worldwide deserts despite differences in total richness and faunal singularity. The degree of nestedness varied among worldwide deserts; however all of them showed a consistent nested pattern. Differences in the degree of nestedness could be a result of different regulating factors depending on the desert and scale. These results highlight the importance of including multiscale approaches when dealing with processes that structure desert communities.  相似文献   

20.
Understanding what processes drive community structure is fundamental to ecology. Many wild animals are simultaneously infected by multiple parasite species, so host–parasite communities can be valuable tools for investigating connections between community structures at multiple scales, as each host can be considered a replicate parasite community. Like free‐living communities, within‐host–parasite communities are hierarchical; ecological interactions between hosts and parasites can occur at multiple scales (e.g., host community, host population, parasite community within the host), therefore, both extrinsic and intrinsic processes can determine parasite community structure. We combine analyses of community structure and assembly at both the host population and individual scales using extensive datasets on wild wood mice (Apodemus sylvaticus) and their parasite community. An analysis of parasite community nestedness at the host population scale provided predictions about the order of infection at the individual scale, which were then tested using parasite community assembly data from individual hosts from the same populations. Nestedness analyses revealed parasite communities were significantly more structured than random. However, observed nestedness did not differ from null models in which parasite species abundance was kept constant. We did not find consistency between observed community structure at the host population scale and within‐host order of infection. Multi‐state Markov models of parasite community assembly showed that a host's likelihood of infection with one parasite did not consistently follow previous infection by a different parasite species, suggesting there is not a deterministic order of infection among the species we investigated in wild wood mice. Our results demonstrate that patterns at one scale (i.e., host population) do not reliably predict processes at another scale (i.e., individual host), and that neutral or stochastic processes may be driving the patterns of nestedness observed in these communities. We suggest that experimental approaches that manipulate parasite communities are needed to better link processes at multiple ecological scales.  相似文献   

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