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The Interplay between Environmental Filtering and Spatial Processes in Structuring Communities: The Case of Neotropical Snake Communities.

Cavalheri H, Both C, Martins M - PLoS ONE (2015)

Bottom Line: Such pattern suggests that the limited distribution of major snake lineages constrained species distributions.Structure indices for each community were also related to habitat type, showing that communities from non-forest areas tend to be more clustered.Our study showed that both environmental filtering and spatial gradients play important roles in shaping the composition of Neotropical snake communities.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, 05508-090, São Paulo, SP, Brazil.

ABSTRACT
Both habitat filters and spatial processes can influence community structure. Space alone affects species immigration from the regional species pool, whereas habitat filters affect species distribution and inter-specific interactions. This study aimed to understand how the interplay between environmental and geographical processes influenced the structure of Neotropical snake communities in different habitat types. We selected six studies that sampled snakes in forests, four conducted in savannas and two in grasslands (the latter two are grouped in a non-forest category). We used the net relatedness and nearest taxon indices to assess phylogenetic structure within forest and non-forest areas. We also used the phylogenetic fuzzy-weighting algorithm to characterize phylogenetic structure across communities and the relation of phylogenetic composition patterns to habitat type, structure, and latitude. Finally, we tested for morphological trait convergence and phylogenetic niche conservatism using four forest and four non-forest areas for which morphological data were available. Community phylogenetic composition changed across forest and non-forest areas suggesting that environmental filtering influences community structure. Species traits were affected by habitat type, indicating convergence at the metacommunity level. Tail length, robustness, and number of ventral scales maximized community convergence among forest and non-forest areas. The observed patterns suggested environmental filtering, indicating that less vertically structured habitats represent a strong filter. Despite the fact that phylogenetic structure was not detected individually for each community, we observed a trend towards communities composed by more closely related species in higher latitudes and more overdispersed compositions in lower latitudes. Such pattern suggests that the limited distribution of major snake lineages constrained species distributions. Structure indices for each community were also related to habitat type, showing that communities from non-forest areas tend to be more clustered. Our study showed that both environmental filtering and spatial gradients play important roles in shaping the composition of Neotropical snake communities.

No MeSH data available.


Phylogenetic tree for snake genera occurring in the eight communities studied.Phylogeny derived from multiple sources (see S2 File). Branch lengths are only illustrative. Major lineages follow [58].
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pone.0127959.g002: Phylogenetic tree for snake genera occurring in the eight communities studied.Phylogeny derived from multiple sources (see S2 File). Branch lengths are only illustrative. Major lineages follow [58].

Mentions: We constructed a topological phylogenetic tree (Fig 2, S1 Fig) including all species from each community, and individual phylogenies for each community, including species of their respective regional species pool (i.e. the species that could potentially compose the communities; see below), based on published phylogenies and personal communications from specialists (S2 File), using the software Mesquite 2.75 [31]. Because branch lengths were not available, analyses were performed by node counting.


The Interplay between Environmental Filtering and Spatial Processes in Structuring Communities: The Case of Neotropical Snake Communities.

Cavalheri H, Both C, Martins M - PLoS ONE (2015)

Phylogenetic tree for snake genera occurring in the eight communities studied.Phylogeny derived from multiple sources (see S2 File). Branch lengths are only illustrative. Major lineages follow [58].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4465701&req=5

pone.0127959.g002: Phylogenetic tree for snake genera occurring in the eight communities studied.Phylogeny derived from multiple sources (see S2 File). Branch lengths are only illustrative. Major lineages follow [58].
Mentions: We constructed a topological phylogenetic tree (Fig 2, S1 Fig) including all species from each community, and individual phylogenies for each community, including species of their respective regional species pool (i.e. the species that could potentially compose the communities; see below), based on published phylogenies and personal communications from specialists (S2 File), using the software Mesquite 2.75 [31]. Because branch lengths were not available, analyses were performed by node counting.

Bottom Line: Such pattern suggests that the limited distribution of major snake lineages constrained species distributions.Structure indices for each community were also related to habitat type, showing that communities from non-forest areas tend to be more clustered.Our study showed that both environmental filtering and spatial gradients play important roles in shaping the composition of Neotropical snake communities.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, 05508-090, São Paulo, SP, Brazil.

ABSTRACT
Both habitat filters and spatial processes can influence community structure. Space alone affects species immigration from the regional species pool, whereas habitat filters affect species distribution and inter-specific interactions. This study aimed to understand how the interplay between environmental and geographical processes influenced the structure of Neotropical snake communities in different habitat types. We selected six studies that sampled snakes in forests, four conducted in savannas and two in grasslands (the latter two are grouped in a non-forest category). We used the net relatedness and nearest taxon indices to assess phylogenetic structure within forest and non-forest areas. We also used the phylogenetic fuzzy-weighting algorithm to characterize phylogenetic structure across communities and the relation of phylogenetic composition patterns to habitat type, structure, and latitude. Finally, we tested for morphological trait convergence and phylogenetic niche conservatism using four forest and four non-forest areas for which morphological data were available. Community phylogenetic composition changed across forest and non-forest areas suggesting that environmental filtering influences community structure. Species traits were affected by habitat type, indicating convergence at the metacommunity level. Tail length, robustness, and number of ventral scales maximized community convergence among forest and non-forest areas. The observed patterns suggested environmental filtering, indicating that less vertically structured habitats represent a strong filter. Despite the fact that phylogenetic structure was not detected individually for each community, we observed a trend towards communities composed by more closely related species in higher latitudes and more overdispersed compositions in lower latitudes. Such pattern suggests that the limited distribution of major snake lineages constrained species distributions. Structure indices for each community were also related to habitat type, showing that communities from non-forest areas tend to be more clustered. Our study showed that both environmental filtering and spatial gradients play important roles in shaping the composition of Neotropical snake communities.

No MeSH data available.