scholarly journals Phylogeographic Diversity of the Lower Central American Cichlid Andinoacara coeruleopunctatus (Cichlidae)

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
S. Shawn McCafferty ◽  
Andrew Martin ◽  
Eldredge Bermingham
Keyword(s):  
Central American ◽  
Ecological Processes ◽  
Cichlid Species ◽  
Biogeographic Patterns ◽  
Relative Contribution ◽  
Drainage Connection ◽  
Important Region ◽  
Dispersal Capability ◽  
Demographic Processes ◽  
Clock Analysis

It is well appreciated that historical and ecological processes are important determinates of freshwater biogeographic assemblages. Phylogeography can potentially lend important insights into the relative contribution of historical processes in biogeography. However, the extent that phylogeography reflects historical patterns of drainage connection may depend in large part on the dispersal capability of the species. Here, we test the hypothesis that due to their relatively greater dispersal capabilities, the neotropical cichlid species Andinoacara coeruleopunctatus will display a phylogeographic pattern that differs from previously described biogeographic assemblages in this important region. Based on an analysis of 318 individuals using mtDNA ATPase 6/8 sequence and restriction fragment length polymorphism data, we found eight distinct clades that are closely associated with biogeographic patterns. The branching patterns among the clades and a Bayesian clock analysis suggest a relatively rapid colonization and diversification among drainages in the emergent Isthmus of Panama followed by the coalescing of some drainages due to historical connections. We also present evidence for extensive cross-cordillera sharing of clades in central Panama and the Canal region. Our results suggest that contemporary phylogeographic patterns and diversification in Lower Central American fishes reflect an interaction of historical drainage connections, dispersal, and demographic processes.

scholarly journals Molecular and fossil evidence place the origin of cichlid fishes long after Gondwanan rifting

2013 ◽  
Vol 280 (1770) ◽  
pp. 20131733 ◽  
Author(s):  
Matt Friedman ◽  
Benjamin P. Keck ◽  
Alex Dornburg ◽  
Ron I. Eytan ◽  
Christopher H. Martin ◽  
...  
Keyword(s):  
Evolutionary Developmental Biology ◽  
Molecular Clocks ◽  
Distributional Pattern ◽  
Cichlid Species ◽  
Biogeographic Patterns ◽  
Cichlid Fishes ◽  
Clock Analysis ◽  
Model Clade ◽  
Relaxed Molecular Clock ◽  
Relaxed Clock

Cichlid fishes are a key model system in the study of adaptive radiation, speciation and evolutionary developmental biology. More than 1600 cichlid species inhabit freshwater and marginal marine environments across several southern landmasses. This distributional pattern, combined with parallels between cichlid phylogeny and sequences of Mesozoic continental rifting, has led to the widely accepted hypothesis that cichlids are an ancient group whose major biogeographic patterns arose from Gondwanan vicariance. Although the Early Cretaceous ( ca 135 Ma) divergence of living cichlids demanded by the vicariance model now represents a key calibration for teleost molecular clocks, this putative split pre-dates the oldest cichlid fossils by nearly 90 Myr. Here, we provide independent palaeontological and relaxed-molecular-clock estimates for the time of cichlid origin that collectively reject the antiquity of the group required by the Gondwanan vicariance scenario. The distribution of cichlid fossil horizons, the age of stratigraphically consistent outgroup lineages to cichlids and relaxed-clock analysis of a DNA sequence dataset consisting of 10 nuclear genes all deliver overlapping estimates for crown cichlid origin centred on the Palaeocene ( ca 65–57 Ma), substantially post-dating the tectonic fragmentation of Gondwana. Our results provide a revised macroevolutionary time scale for cichlids, imply a role for dispersal in generating the observed geographical distribution of this important model clade and add to a growing debate that questions the dominance of the vicariance paradigm of historical biogeography.

scholarly journals Deciphering Centimeter-Scale Microbial Biogeographic Patterns and Community Assembly Processes From A 3D Perspective

2020 ◽  
Author(s):  
Ran Xue ◽  
Kankan Zhao ◽  
Xiuling Yu ◽  
Erinne Stirling ◽  
Shan Liu ◽  
...  
Keyword(s):  
Microbial Community ◽  
Variable Selection ◽  
Microbial Diversity ◽  
Community Assembly ◽  
Sampling Strategy ◽  
Sampling Scheme ◽  
Ecological Processes ◽  
Soil Matrix ◽  
Biogeographic Patterns ◽  
2D To 3D

Abstract Background: Revealing the effects of multi-dimensional spatial distribution on microorganisms is crucial for the further understanding of microbial diversity, turnover and ecological processes. However, microbial community assembly and the factors that shape it are still unknown from a three dimensional (3D) perspective. Here, a 3D model was created by performing an exhaustive sampling strategy to a 4x4x4 soil matrix. We examined the dynamics of microbial diversity, biogeographic patterns and microbial assembly processes when transfroming sampling scheme from 2D to 3D.Results: Our results indicated that dispersion of microbial community and significance of distance decay relationship was higher in the 3D compared with 2D sampling scheme, suggesting increased microbial turnover when transforming the model from 2D to 3D. Only a small fraction of community variation can be explained by environmental, spatial factors and spatial canonical axes, possibly due to unmeasured environmental variables. The assembly of microbial community was dominated by deterministic processes that shifted from homogeneous selection to variable selection as we transformed the model from 2D to 3D. The importance of stochasticity increased when homogeneous and variable selection processes were well balanced. However, heterogeneity of existing environmental and spatial variables failed to explain the dynamics of community assembly.Conclusions: Our study revealed significant dynamics of microbial diversity and assembly processes when assessed from 2D and 3D perspectives. As microorganisms are spatially distributed in soil, this spatial dependent diversity and assembly suggests that microbial ecological questions need to be considered in more dimensions than they usually are. Further, new models that integrate all data sets are still needed to disengle the microbial processes in multiple dimensions.

Nocturnal activity by the primarily diurnal Central American agouti (Dasyprocta punctata) in relation to environmental conditions, resource abundance and predation risk

2009 ◽  
Vol 25 (2) ◽  
pp. 211-215 ◽  
Author(s):  
Thomas D. Lambert ◽  
Roland W. Kays ◽  
Patrick A. Jansen ◽  
Enzo Aliaga-Rossel ◽  
Martin Wikelski
Keyword(s):  
Social Interactions ◽  
Predation Risk ◽  
Environmental Conditions ◽  
Central American ◽  
Nocturnal Activity ◽  
Ecological Processes ◽  
Resource Abundance ◽  
Gain Access

An animal's fitness is in part based on its ability to manage the inherent risks (foraging costs, predation, exposure to disease) with the benefits (resource gain, access to mates, social interactions) of activity (Abrams 1991, Altizer et al. 2003, Lima & Bednekoff 1999, Rubenstein & Hohmann 1989, Wikelski et al. 2001). Thus, understanding an animal's pattern of activity is key to understanding behavioural and ecological processes. However, while numerous laboratory methodologies are available to continuously quantify activity over long periods of time, logistical difficulties have greatly hindered activity studies of animals in the field (DeCoursey 1990).

scholarly journals Lactifluus (Russulaceae) diversity in Central America and the Caribbean: melting pot between realms

2020 ◽  
Vol 44 (1) ◽  
pp. 278-300
Author(s):  
L. Delgat ◽  
R. Courtecuisse ◽  
E. De Crop ◽  
F. Hampe ◽  
T.A. Hofmann ◽  
...  
Keyword(s):  
Central America ◽  
Central American ◽  
Melting Pot ◽  
Biogeographic Patterns ◽  
North American Continent ◽  
Caribbean Islands ◽  
The North ◽  
The Caribbean ◽  
Three New Species ◽  
Different Origins

Species of the ectomycorrhizal genus Lactifluus, and often entire sections, are typically unique to a single continent. Given these biogeographic patterns, an interesting region to study their diversity is Central America and the Caribbean, since the region is closely connected to and often considered a part of the North American continent, but biogeographically belong to the Neotropical realm, and comprises several regions with different geologic histories. Based on a multi-gene phylogeny and morphological study, this study shows that Central America, Mexico and the Caribbean harbour at least 35 Lactifluus species, of which 33 were never reported outside of this region. It was found that species from the Caribbean generally show affinities to South American taxa, while species from the Central American mainland generally show affinities to Northern hemispheric taxa. We hypothesise that host specificity and/or climate play a crucial role in these different origins of diversity. Because of these different affinities, Caribbean islands harbour a completely different Lactifluus diversity than the Central American mainland. The majority of species occurring on the islands can be considered endemic to certain islands or island groups. In this paper, detailed morphological descriptions are given, with a focus on the unique diversity of the islands, and identification keys to all hitherto described Lactifluus species occurring in Central America and the Caribbean are provided. One new section, Lactifluus sect. Nebulosi, and three new species, Lactifluus guadeloupensis, Lactifluus lepus and Lactifluus marmoratus are described.

scholarly journals Biogeographic patterns of belemnite body size responses to episodes of environmental crisis

2019 ◽  
Author(s):  
Patrícia Rita ◽  
José C. García-Ramos ◽  
Pascal Neige ◽  
Laura Piñuela ◽  
Robert Weis ◽  
...  
Keyword(s):  
Body Size ◽  
The Body ◽  
The Other ◽  
Environmental Crisis ◽  
Oceanic Anoxic Event ◽  
Biogeographic Patterns ◽  
Relative Contribution ◽  
Other Hand ◽  
Marine Diversity ◽  
Abundance And Diversity

Body size changes have been investigated through episodes of environmental crisis among several groups of organisms but the relative contribution of within-lineage size changes, selective extinction and origination of taxa on these patterns is still being debated. Rapid warming, anoxia, and perturbations of the carbon cycle linked with volcanic activity, as well as their impact on marine diversity are well documented for the Pliensbachian-Toarcian (Pli-Toa) boundary and for the Toarcian Oceanic Anoxic Event (T-OAE). Belemnites were a very abundant and successful cephalopod group in the Mesozoic oceans playing a paramount role in the oceanic trophic webs. Belemnites have mainly been studied from a geochemical perspective during this interval. Newly collected data from three northern and western Iberian sections (Peniche, Rodiles and Lastres) allowed an analysis of the belemnite body size dynamics across the Pli-Toa boundary and the T-OAE and a comparison with other European basins. In Peniche (Lusitanian Basin, Portugal), a significant reduction in belemnite body size was recognized across the Pli-Toa boundary at the assemblage level (i.e. community scale of organization). From the analysis of the different taxa recorded, it seems that adult specimens of Pseudohastites longiformis are driving the body size pattern observed (13% rostrum size decrease). The uppermost Polymorphum-Levisoni zones interval is characterized by a dramatic decrease on both belemnite abundance and diversity. Only 4 specimens of the genus Acrocoelites were found, increasing the body size at the assemblage level. In the Asturian Basin (N Spain), on the other hand, a body size increase at the assemblage level is recognized across the Pli-Toa boundary caused by a within-lineage effect mainly related to adult specimens of Passaloteuthis and Pseudohastites genera. During the onset of the T-OAE, belemnite body size increases due to the appearance of Acrocoelites genus. To summarize, the increase in rostrum size at the assemblage level across the T-OAE is associated with the radiation of a large-sized taxon (Acrocoelites genus) and the extinction of various other species. On the other hand, across the Pli-Toa boundary, the belemnite body size changes are dominated by within-lineage mechanisms. This suggests that species might have been able to cope within the early warming phase (Pli-Ta boundary), but were more affected by the subsequent warming and anoxia during the T-OAE. Our preliminary results indicate that this pattern might also be recognized in other western European sections, such as Cleveland Basin, western Paris Basin (Normandy) and Southern Germany sections. The biotic and abiotic drivers of belemnite body size changes still need to be comprehensively analyzed.

scholarly journals The role of social and ecological processes in structuring animal populations: a case study from automated tracking of wild birds

2015 ◽  
Vol 2 (4) ◽  
pp. 150057 ◽  
Author(s):  
Damien R. Farine ◽  
Josh A. Firth ◽  
Lucy M. Aplin ◽  
Ross A. Crates ◽  
Antica Culina ◽  
...  
Keyword(s):  
Evolutionary Ecology ◽  
Preferential Attachment ◽  
Ecological Factors ◽  
Phenotypic Selection ◽  
Ecological Processes ◽  
Population Process ◽  
Relative Contribution ◽  
Animal Populations ◽  
Two Factors ◽  
Phenotypic Structure

Both social and ecological factors influence population process and structure, with resultant consequences for phenotypic selection on individuals. Understanding the scale and relative contribution of these two factors is thus a central aim in evolutionary ecology. In this study, we develop a framework using null models to identify the social and spatial patterns that contribute to phenotypic structure in a wild population of songbirds. We used automated technologies to track 1053 individuals that formed 73 737 groups from which we inferred a social network. Our framework identified that both social and spatial drivers contributed to assortment in the network. In particular, groups had a more even sex ratio than expected and exhibited a consistent age structure that suggested local association preferences, such as preferential attachment or avoidance. By contrast, recent immigrants were spatially partitioned from locally born individuals, suggesting differential dispersal strategies by phenotype. Our results highlight how different scales of social decision-making, ranging from post-natal dispersal settlement to fission–fusion dynamics, can interact to drive phenotypic structure in animal populations.

scholarly journals Vertical Niche Partitioning of Archaea and Bacteria Linked to Shifts in Dissolved Organic Matter Quality and Hydrography in North Atlantic Waters

2021 ◽  
Vol 8 ◽  
Author(s):  
Tamara Rodríguez-Ramos ◽  
Mar Nieto-Cid ◽  
Adrià Auladell ◽  
Elisa Guerrero-Feijóo ◽  
Marta M. Varela
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Beta Diversity ◽  
High Salinity ◽  
Niche Partitioning ◽  
Sequence Variant ◽  
Ecological Processes ◽  
Organic Matter Quality ◽  
Biogeographic Patterns ◽  
Bacterial Assemblages

Understanding the factors that modulate prokaryotic assemblages and their niche partitioning in marine environments is a longstanding challenge in marine microbial ecology. This study analyzes amplicon sequence variant (ASV) diversity and co-occurrence of prokaryotic (Archaea and Bacteria) communities through coastal-oceanic gradients in the NW Iberian upwelling system and adjacent open-ocean (Atlantic Ocean). Biogeographic patterns were investigated in relation with environmental conditions, mainly focusing on the optical signature of the dissolved organic matter (DOM). Alpha- and beta-diversity were horizontally homogeneous [with the only exception of Archaea (∼1700 m depth), attributed to the influence of Mediterranean water, MW], while beta-diversity was significantly vertically stratified. Prokaryotic communities were structured in four clusters (upper subsurface, lower subsurface, intermediate, and deep clusters). Deep (>2000 m) archaeal and bacterial assemblages, and intermediate (500-2000 m) Bacteria (mainly SAR202 and SAR406), were significantly related to humic-like DOM (FDOM-M), while intermediate Archaea were additionally related to biogeochemical attributes of the high-salinity signature of MW. Lower subsurface (100-500 m) Archaea (particularly one ASV belonging to the genus Candidatus Nitrosopelagicus) were mainly related to the imprint of high-salinity MW, while upper subsurface (≤100 m) archaeal assemblages (particularly some ASVs belonging to Marine Group II) were linked to protein-like DOM (aCDOM254). Conversely, both upper and lower subsurface bacterial assemblages were mainly linked to aCDOM254 (particularly ASVs belonging to Rhodobacteraceae, Cyanobacteria, and Flavobacteriaceae) and nitrite concentration (mainly members of Planctomycetes). Most importantly, our analysis unveiled depth-ecotypes, such as the ASVs MarG.II_1 belonging to the archaeal deep cluster (linked to FDOM-M) and MarG.II_2 belonging to the upper subsurface cluster (related to FDOM-T and aCDOM254). This result strongly suggests DOM-mediated vertical niche differentiation, with further implications for ecosystem functioning. Similarly, positive and negative co-occurrence relationships also suggested niche partitioning (e.g., between the closely related ASVs Thaum._Nit._Nit._Nit._1 and _2) and competitive exclusion (e.g., between Thaum._Nit._Nit._Nit._4 and _5), supporting the finding of non-randomly, vertically structured prokaryotic communities. Overall, differences between Archaea and Bacteria and among closely related ASVs were revealed in their preferential relationship with compositional changes in the DOM pool and environmental forcing. Our results provide new insights on the ecological processes shaping prokaryotic assembly and biogeography.

scholarly journals Diversity and Biogeography of Bathyal and Abyssal Seafloor Bacteria and Archaea Along a Mediterranean—Atlantic Gradient

2021 ◽  
Vol 12 ◽  
Author(s):  
Blandine Trouche ◽  
Miriam I. Brandt ◽  
Caroline Belser ◽  
Covadonga Orejas ◽  
Stéphane Pesant ◽  
...  
Keyword(s):  
Eastern Mediterranean ◽  
Regional Scale ◽  
Dispersal Limitation ◽  
Sediment Depth ◽  
Western Atlantic ◽  
Microbial Life ◽  
Biogeographic Patterns ◽  
Relative Contribution ◽  
Basin Water ◽  
Seafloor Sediments

Seafloor sediments cover the majority of planet Earth and microorganisms inhabiting these environments play a central role in marine biogeochemical cycles. Yet, description of the biogeography and distribution of sedimentary microbial life is still too sparse to evaluate the relative contribution of processes driving this distribution, such as the levels of drift, connectivity, and specialization. To address this question, we analyzed 210 archaeal and bacterial metabarcoding libraries from a standardized and horizon-resolved collection of sediment samples from 18 stations along a longitudinal gradient from the eastern Mediterranean to the western Atlantic. Overall, we found that biogeographic patterns depended on the scale considered: while at local scale the selective influence of contemporary environmental conditions appeared strongest, the heritage of historic processes through dispersal limitation and drift became more apparent at regional scale, and ended up superseding contemporary influences at inter-regional scale. When looking at environmental factors, the structure of microbial communities was correlated primarily with water depth, with a clear transition between 800 and 1,200 meters below sea level. Oceanic basin, water temperature, and sediment depth were other important explanatory parameters of community structure. Finally, we propose increasing dispersal limitation and ecological drift with sediment depth as a probable factor for the enhanced divergence of deeper horizons communities.

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