Functional richness, functional evenness, and use of niche space in parasite communities.

نویسندگان

  • Devon B Keeney
  • Robert Poulin
چکیده

Most efforts aimed at elucidating the factors responsible for the variation in species richness among different parasite communities have focused on host characteristics such as body mass or diet. Independently of host features, however, the way in which parasites use resources within the host may also affect the species richness of the community. The distribution of parasite individuals or biomass in niche space determines whether host resources are used evenly, or whether there are gaps in resource use, with some parts of the total niche being underutilized. Here, the concepts of functional richness and functional evenness are applied to parasite communities for the first time, using simple indices. Measurements of the distribution of species in niche space within communities, such as mapping the distribution of helminths along the length of the host's intestine, is standard practice in parasitology. In such cases, functional richness is simply the proportion of the total number of intestine sections available that are used by at least 1 worm, whereas functional evenness measures the evenness in the distribution of worm numbers or biomass across all niche sections that are occupied. Data on cestode communities of elasmobranchs are used to illustrate the use of these indices, and to show how important they can be in tests of ecological hypotheses. The indices presented here capture essential features of resource use in parasite communities, and can be useful tools for comparative analyses.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Biology, chance, or history? The predictable reassembly of temperate grassland communities.

Many studies have examined invasion resistance in plant communities, but few have explored the mechanisms of invasion and how subsequent community reassembly affects community functioning. Using natural dispersal and deliberate seed addition into grassland communities with different compositional and richness histories, we show that invaders establish in a nonrandom manner due to negative effec...

متن کامل

Temporal Change in Functional Richness and Evenness in the Eastern African Plio-Pleistocene Carnivoran Guild

We analyze functional richness and functional evenness of the carnivoran guild in eastern Africa from 3.5 Ma to 1.5 Ma, and compare them to the present day. The data consist of characters of the craniodental apparatus of 76 species of fossil and extant carnivorans, divided into four 0.5 Ma time slices from 3.5 to 1.5 Ma, together with the modern fauna. Focus is on large (>21.5 kg) carnivores. R...

متن کامل

Evaluation of the effects of biological operations on functional diversity and soil of carbon stock (Case study: Arange watershed, Alborz province)

 Communities or ecosystems with higher biodiversity also have higher levels of ecosystem function and services, so the relationship between functional diversity and sustainability of plant communities is essential to predict ecosystem functioning. The aim of the present study was to investigate the relationship between carbon stocks and different species diversity and functional indices as well...

متن کامل

New multidimensional functional diversity indices for a multifaceted framework in functional ecology.

Functional diversity is increasingly identified as an important driver of ecosystem functioning. Various indices have been proposed to measure the functional diversity of a community, but there is still no consensus on which are most suitable. Indeed, none of the existing indices meets all the criteria required for general use. The main criteria are that they must be designed to deal with sever...

متن کامل

Changes in Bird Functional Diversity across Multiple Land Uses: Interpretations of Functional Redundancy Depend on Functional Group Identity

Examinations of the impact of land-use change on functional diversity link changes in ecological community structure driven by land modification with the consequences for ecosystem function. Yet, most studies have been small-scale, experimental analyses and primarily focussed on plants. There is a lack of research on fauna communities and at large-scales across multiple land uses. We assessed c...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • The Journal of parasitology

دوره 93 1  شماره 

صفحات  -

تاریخ انتشار 2007