Intraspecific diversity in an ecological engineer functionally trumps interspecific diversity in shaping community structure

Ecosystem Function

Eco-evolutionary Dynamics ◽

10.23943/princeton/9780691145433.003.0009 ◽

2016 ◽

Author(s):

Andrew P. Hendry

Keyword(s):

Community Structure ◽

Conceptual Framework ◽

Time Scales ◽

Ecosystem Function ◽

Evolutionary Dynamics ◽

Relative Strength ◽

Intraspecific Diversity ◽

Empirical Methods ◽

Ecosystem Level ◽

Key Questions

This chapter explores how the mathematical frameworks, empirical methods, and predictions introduced for community structure can be extended to ecosystem function. Also outlined is an alternative conceptual framework (biological stoichiometry) for evaluating eco-evolutionary dynamics at the ecosystem level. The key questions in this analysis include the importance of intraspecific diversity, the relative strength of the various effects, on what time scales do the effects play out, and to what extent are the effects direct or indirect. The chapter also addresses whether the effects of genotypes decrease toward higher levels of complexity (from phenotypes to communities to ecosystems), and to what extent feedbacks are evident-traits influence ecosystems which then influence traits.

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Fine-scale community and genetic structure are tightly linked in species-rich grasslands

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2010.0329 ◽

2011 ◽

Vol 366 (1569) ◽

pp. 1346-1357 ◽

Cited By ~ 8

Author(s):

Raj Whitlock ◽

Mark C. Bilton ◽

J. Phil Grime ◽

Terry Burke

Keyword(s):

Community Structure ◽

Species Coexistence ◽

Interspecific Interactions ◽

Genetic Effects ◽

Intraspecific Diversity ◽

Fine Scale ◽

Grassland Community ◽

Indirect Genetic Effects ◽

Coexisting Species ◽

The Impact

Recent evidence indicates that grassland community structure and species diversity are influenced by genetic variation within species. We review what is known regarding the impact of intraspecific diversity on grassland community structure, using an ancient limestone pasture as a focal example. Two genotype-dependent effects appear to modify community structure in this system. First, the abundance of individual constituent species can depend upon the combined influence of direct genetic effects stemming from individuals within the population. Second, the outcome of localized interspecific interactions occurring within the community can depend on the genotypes of participating individuals (indicating indirect genetic effects). Only genotypic interactions are thought to be capable of allowing the long-term coexistence of both genotypes and species. We discuss the implications of these effects for the maintenance of diversity in grasslands. Next, we present new observations indicating that losses of genotypic diversity from each of two species can be predicted by the abundance of other coexisting species within experimental grassland communities. These results suggest genotype-specific responses to abundance in other coexisting species. We conclude that both direct and indirect genetic effects are likely to shape community structure and species coexistence in grasslands, implying tight linkage between fine-scale genetic and community structure.

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Community Structure

Eco-evolutionary Dynamics ◽

10.23943/princeton/9780691145433.003.0008 ◽

2016 ◽

Author(s):

Andrew P. Hendry

Keyword(s):

Genetic Diversity ◽

Community Structure ◽

Empirical Work ◽

Community Change ◽

Phenotypic Change ◽

Predator Prey ◽

Current State ◽

Intraspecific Genetic Diversity ◽

Community Theory ◽

Interspecific Diversity

This chapter begins with an outline of mathematical approaches for evaluating how genotypes/phenotypes might alter community structure, which points to predictions about when such effects should be strongest in nature. It then summarizes common approaches for empirical work, which might be broadly classed as (1) the effects of genotypes/phenotypes within and among populations, and (2) the year-by-year correspondence between phenotypic change and community change. These key questions examine the current state of knowledge for two classic applications of evolutionary thinking to community theory: predator–prey interactions and competition. The chapter also considers the importance of intraspecific genetic diversity for community structure, which echoes and extends the intense interest surrounding the effects of interspecific diversity.

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Epidemiology, species composition and genetic diversity of tetra- and octonucleated Entamoeba spp. in different Brazilian biomes

Parasites & Vectors ◽

10.1186/s13071-021-04672-y ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Deiviane Aparecida Calegar ◽

Kerla Joeline Lima Monteiro ◽

Polyanna Araújo Alves Bacelar ◽

Brenda Bulsara Costa Evangelista ◽

Mayron Morais Almeida ◽

...

Keyword(s):

Atlantic Forest ◽

Phylogenetic Trees ◽

Small Subunit ◽

Ssu Rdna ◽

Intraspecific Diversity ◽

Cross Sectional ◽

Fecal Samples ◽

E Coli ◽

Microscopy Analysis ◽

Interspecific Diversity

Abstract Background Entamoeba species harbored by humans have different degrees of pathogenicity. The present study explores the intra- and interspecific diversity, phylogenetic relationships, prevalence and distribution of tetra- and octonucleated cyst-producing Entamoeba in different Brazilian regions. Methods Cross-sectional studies were performed to collect fecal samples (n = 1728) and sociodemographic data in communities located in four Brazilian biomes: Atlantic Forest, Caatinga, Cerrado, and Amazon. Fecal samples were subjected to molecular analysis by partial small subunit ribosomal DNA sequencing (SSU rDNA) and phylogenetic analysis. Results Light microscopy analysis revealed that tetranucleated cysts were found in all the studied biomes. The highest positivity rates were observed in the age group 6–10 years (23.21%). For octonucleated cysts, positivity rates ranged from 1 to 55.1%. Sixty SSU rDNA Entamoeba sequences were obtained, and four different species were identified: the octonucleated E. coli, and the tetranucleated E. histolytica, E. dispar, and E. hartmanni. Novel haplotypes (n = 32) were characterized; however, new ribosomal lineages were not identified. The Entamoeba coli ST1 subtype predominated in Atlantic Forest and Caatinga, and the ST2 subtype was predominant in the Amazon biome. E. histolytica was detected only in the Amazon biome. In phylogenetic trees, sequences were grouped in two groups, the first containing uni- and tetranucleated and the second containing uni- and octonucleated cyst-producing Entamoeba species. Molecular diversity indexes revealed a high interspecific diversity for tetra- and octonucleated Entamoeba spp. (H ± SD = 0.9625 ± 0.0126). The intraspecific diversity varied according to species or subtype: E. dispar and E. histolytica showed lower diversity than E. coli subtypes ST1 and ST2 and E. hartmanni. Conclusions Tetra- and octonucleated cyst-producing Entamoeba are endemic in the studied communities; E. histolytica was found in a low proportion and only in the Amazon biome. With regard to E. coli, subtype ST2 was predominant in the Amazon biome. The molecular epidemiology of Entamoeba spp. is a field to be further explored and provides information with important implications for public health.

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STRUKTUR KOMUNITAS MAKRO ALGA DI PESISIR PULAU KECAMATAN BULANG

SIMBIOSA ◽

10.33373/sim-bio.v3i2.282 ◽

2014 ◽

Vol 3 (2) ◽

Author(s):

Notowinarto Notowinarto ◽

Ramses Ramses ◽

Mulhairi Mulhairi

Keyword(s):

Community Structure ◽

Diversity Index ◽

Algal Species ◽

Algal Communities ◽

Marine Life ◽

Ph Values ◽

Abundance Patterns ◽

Coastal Marine ◽

Temperature Parameter ◽

Important Value Index

Bulang districts Batam Islands of Riau province (Riau Islands), its consists of many islands with as well as having the potential diversity of coastal marine life in particular kinds of macro algae or seaweed. Conducted research aimed to determine the structure of macro- algal communities in the intertidal zone islands. The results of the identification of algal species found 16 species are: the Order of Chlorophyceae as 6 spesies; Order Phaeophyceae as 2 spesies; and Order Rhodophyceae as 8 spesies. The community structure at the five stations showed the highest values were found in the island of dominance Cicir (D ' = 0.79) , uniformity index values on Tengah Island (E ' = 0.99) , while the island Balak had the highest diversity index (H ' = 0.88) , with the abundance patterns of population structure on the island is pretty good Central . Results of correlation analysis of regression between IVI types of algae with the conditions of environmental quality suggests that there is a significance (Fhit ˃ F table and the value of r = > 90 %) between IVI algae Halimeda sp and Cryptarachne polyglandulosa at each station with a temperature parameter surface (⁰C) , depth temperature (⁰C) and pH values. Keywords : Algae, Community Structure, Important Value Index.

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