The Role of Geography and Ecological Opportunity in the Diversification of Day Geckos (Phelsuma)

ABSTRACTAmong vertebrates, placental mammals are particularly variable in the covariance between their cranial shapes and body size (allometry), with the notable exception of rodents. Australian murid rodents present an opportunity to assess the cause of this anomaly because they radiated on an ecologically diverse continent unique for lacking other terrestrial placentals. Here we used 3D geometric morphometrics to quantify species-level and evolutionary allometries in 38 species (317 crania) from all Australian murid genera. We ask if ecological opportunity resulted in greater allometric diversity; conversely, we test if intrinsic constraints and/or stabilizing selection conserved allometry. To increase confidence in species-level allometric slopes, we introduce a new phylogeny-based method of bootstrapping and randomly resampling across the whole sample. We found exceedingly conserved allometry across the 10 million year split between Mus and the clade containing Australian murids. Cranial shapes followed craniofacial evolutionary allometry (CREA) patterns, with larger species having relatively longer snouts and smaller braincases. CREA is consistent with both intrinsic constraints and stabilizing selection hypotheses for conserved allometry. However, large-bodied frugivores evolved faster, while carnivorous specialists showed skull modifications known to conflict with masticatory efficiency. These results suggest a strong role of stabilizing selection on the masticatory apparatus of murid rodents.

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The role of phylogeny and ecological opportunity in host-parasite interactions: network metrics, host repertoire, and network link prediction.

10.22541/au.163274253.31016446/v1 ◽

2021 ◽

Author(s):

Armando Cruz-Laufer ◽

Tom Artois ◽

Stephan Koblmüller ◽

Antoine Pariselle ◽

Karen Smeets ◽

...

Keyword(s):

Link Prediction ◽

Ecological Opportunity ◽

Ecological Fitting ◽

Parasite Communities ◽

Network Link ◽

Taxonomic Research ◽

Gill Parasites ◽

Host Parasite ◽

Network Metrics

Hosts and parasites have often intimate associations. Therefore, the evolution of their interactions is crucial for understanding species-rich host-parasite communities. Yet relatively few studies investigate eco-evolutionary feedbacks in these systems as large datasets remain scarce. Here, we explore African cichlid fishes and their flatworm gill parasites (Cichlidogyrus spp.) including 9901 reported infections and 473 different host-parasite combinations collected through a survey of peer-reviewed literature. We apply network metrics, estimate host repertoires, and use network link prediction (NLP) algorithms to investigate meta-community structures and their predictors including evolutionary, ecological, and morphological parameters. Host repertoire was mostly determined by the hosts’ evolutionary history. Both ecological and evolutionary parameters predicted host parasite associations but many interactions remain undetected according to NLP. We conclude that ecological opportunity paired with ecological fitting has shaped interactions. The cichlid-Cichlidogyrus network is a suitable study system for eco-evolutionary feedbacks but taxonomic research remains key to finding undetected interactions.

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The role of ecological opportunity in shaping disparate diversification trajectories in a bicontinental primate radiation

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.1979 ◽

2014 ◽

Vol 281 (1781) ◽

pp. 20131979 ◽

Cited By ~ 12

Author(s):

Lucy A. P. Tran

Keyword(s):

Phenotypic Diversity ◽

Dietary Specialization ◽

Ecological Opportunity ◽

Biogeographic History ◽

Key Innovation ◽

Colobine Monkeys ◽

Foregut Fermentation ◽

Herbivorous Species ◽

African Clade

Exceptional species and phenotypic diversity commonly are attributed to ecological opportunity (EO). The conventional EO model predicts that rates of lineage diversification and phenotypic evolution are elevated early in a radiation only to decline later in response to niche availability. Foregut fermentation is hypothesized to be a key innovation that allowed colobine monkeys (subfamily Colobinae), the only primates with this trait, to successfully colonize folivore adaptive zones unavailable to other herbivorous species. Therefore, diversification rates also are expected to be strongly linked with the evolution of traits related to folivory in these monkeys. Using dated molecular phylogenies and a dataset of feeding morphology, I test predictions of the EO model to evaluate the role of EO conferred by foregut fermentation in shaping the African and Asian colobine radiations. Findings from diversification methods coupled with colobine biogeographic history provide compelling evidence that decreasing availability of new adaptive zones during colonization of Asia together with constraints presented by dietary specialization underlie temporal changes in diversification in the Asian but not African clade. Additionally, departures from the EO model likely reflect iterative diversification events in Asia.

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Ecological causes of uneven speciation and species richness in mammals

10.1101/504803 ◽

2019 ◽

Cited By ~ 12

Author(s):

Nathan S. Upham ◽

Jacob A. Esselstyn ◽

Walter Jetz

Keyword(s):

Species Richness ◽

Species Turnover ◽

Rate Variation ◽

Ecological Traits ◽

Ecological Opportunity ◽

Diversification Rates ◽

Speciation Rate ◽

Diversity Gradient ◽

Speciation Rates

ABSTRACTBiodiversity is distributed unevenly from the poles to the equator, and among branches of the tree of life, yet how those enigmatic patterns are related is unclear. We investigated global speciation-rate variation across crown Mammalia using a novel time-scaled phylogeny (N=5,911 species, ~70% with DNA), finding that trait- and latitude-associated speciation has caused uneven species richness among groups. We identify 24 branch-specific shifts in net diversification rates linked to ecological traits. Using time-slices to define clades, we show that speciation rates are a stronger predictor of clade richness than age. Speciation is slower in tropical than extra-tropical lineages, but only at the level of clades not species tips, consistent with fossil evidence that the latitudinal diversity gradient may be a relatively young phenomenon in mammals. In contrast, species tip rates are fastest in mammals that are low dispersal or diurnal, consistent with models of ephemeral speciation and ecological opportunity, respectively. These findings juxtapose nested levels of diversification, suggesting a central role of species turnover gradients in generating uneven patterns of modern biodiversity.

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The role of ecological opportunity in shaping host–parasite networks

Parasitology ◽

10.1017/s003118202000133x ◽

2020 ◽

Vol 147 (13) ◽

pp. 1452-1460

Author(s):

Elvira D'Bastiani ◽

Karla M. Campião ◽

Walter A. Boeger ◽

Sabrina B. L. Araújo

Keyword(s):

Body Size ◽

Theoretical Models ◽

Interaction Networks ◽

Ecological Opportunity ◽

Host Body ◽

Seasonally Flooded ◽

Brazilian Pantanal ◽

Host Parasite ◽

Host Body Size

AbstractDespite the great interest to quantify the structure of host–parasite interaction networks, the real influence of some factors such as taxonomy, host body size and ecological opportunity remains poorly understood. In this paper, we investigate the general patterns of organization and structure of interactions in two anuran–parasite networks in the Brazilian Pantanal (seasonally flooded environment) and Atlantic Forest (non-flooded forest). We present theoretical models to test whether the structures of these host–parasite interaction networks are influenced by neutrality, host taxonomy and host body size. Subsequently, we calculated metrics of connectance, nestedness and modularity to characterize the network structure. We demonstrated the structure networks were influenced mainly by body size and taxonomy of the host. Moreover, our results showed that the seasonally flooded environment present networks with higher connectance/nestedness and lower modularity compared to the other environment. The results also suggest that seasonal floods may promote ecological opportunities for new species associations.

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Continental cichlid radiations: functional diversity reveals the role of changing ecological opportunity in the Neotropics

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.0556 ◽

2016 ◽

Vol 283 (1836) ◽

pp. 20160556 ◽

Cited By ~ 15

Author(s):

Jessica Hilary Arbour ◽

Hernán López-Fernández

Keyword(s):

Central America ◽

Adaptive Radiation ◽

Morphological Diversity ◽

Evolutionary Rates ◽

Ecological Niches ◽

Ecological Opportunity ◽

Ecological Release ◽

Adaptive Radiations ◽

Lineage Diversification

Adaptive radiations have been hypothesized to contribute broadly to the diversity of organisms. Models of adaptive radiation predict that ecological opportunity and ecological release, the availability of empty ecological niches and the response by adapting lineages to occupy them, respectively, drive patterns of phenotypic and lineage diversification. Adaptive radiations driven by ‘ecological opportunity’ are well established in island systems; it is less clear if ecological opportunity influences continent-wide diversification. We use Neotropical cichlid fishes to test if variation in rates of functional evolution is consistent with changing ecological opportunity. Across a functional morphological axis associated with ram–suction feeding traits, evolutionary rates declined through time as lineages diversified in South America. Evolutionary rates of ram–suction functional morphology also appear to have accelerated as cichlids colonized Central America and encountered renewed opportunity. Our results suggest that ecological opportunity may play an important role in shaping patterns of morphological diversity of even broadly distributed lineages like Neotropical cichlids.

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Role of dactinomycin in the improved survival of children with Wilms' tumor

JAMA ◽

10.1001/jama.195.12.1005 ◽

1966 ◽

Vol 195 (12) ◽

pp. 1005-1009 ◽

Cited By ~ 18

Author(s):

D. J. Fernbach

Keyword(s):

Wilms Tumor

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Role of the allergist in diagnosis and management of patients with uveitis

JAMA ◽

10.1001/jama.195.3.167 ◽

1966 ◽

Vol 195 (3) ◽

pp. 167-172 ◽

Cited By ~ 2

Author(s):

T. E. Van Metre

Keyword(s):

Diagnosis And Management

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The power of norms to sway fused group members

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001644 ◽

2018 ◽

Vol 41 ◽

Cited By ~ 1

Author(s):

Winnifred R. Louis ◽

Craig McGarty ◽

Emma F. Thomas ◽

Catherine E. Amiot ◽

Fathali M. Moghaddam

Keyword(s):

Evolutionary Anthropology ◽

Normative Systems ◽

Violent Extremism ◽

Identity Fusion ◽

Group Members

AbstractWhitehouse adapts insights from evolutionary anthropology to interpret extreme self-sacrifice through the concept of identity fusion. The model neglects the role of normative systems in shaping behaviors, especially in relation to violent extremism. In peaceful groups, increasing fusion will actually decrease extremism. Groups collectively appraise threats and opportunities, actively debate action options, and rarely choose violence toward self or others.

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