Punctual ecological changes rather than global factors drive species diversification and the evolution of wing phenotypes in Morpho butterflies

AbstractAssessing the relative importance of geographical and ecological drivers of evolution is paramount to understand the diversification of species and traits at the macroevolutionary scale. Here, we use an integrative approach, combining phylogenetics, biogeography, ecology, and quantified phenotypes to investigate the drivers of both species and phenotypic diversification of the iconic Neotropical butterfly genus Morpho. We generated a time-calibrated phylogeny for all known species and inferred historical biogeography. We fitted models of time-dependent (accounting for rate heterogeneity across the phylogeny) and paleoenvironment-dependent diversification (accounting for global effect on the phylogeny). We used geometric morphometrics to assess variation of wing size and shape across the tree, and investigated their dynamics of evolution. We found that the diversification of Morpho is best explained when considering multiple independent diversification dynamics across the tree, possibly associated with lineages occupying different microhabitat conditions. First, a shift from understory to canopy was characterized by an increased speciation rate partially coupled with an increasing rate of wing shape evolution. Second, the occupation of dense bamboo thickets accompanying a major host-plant shift from dicotyledons towards monocotyledons was associated with a simultaneous diversification rate shift and an evolutionary “jump” of wing size. Our study points to a diversification pattern driven by punctual ecological changes instead of a global driver or biogeographic history.

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Little evidence for enhanced phenotypic evolution in early teleosts relative to their living fossil sister group

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1607237113 ◽

2016 ◽

Vol 113 (41) ◽

pp. 11531-11536 ◽

Cited By ~ 41

Author(s):

John T. Clarke ◽

Graeme T. Lloyd ◽

Matt Friedman

Keyword(s):

Evolutionary Rate ◽

Sister Group ◽

Shape Evolution ◽

Phenotypic Evolution ◽

Crown Group ◽

Living Fossil ◽

Jaw Mechanics ◽

Phenotypic Diversification ◽

Body Shapes ◽

Lineage Diversification

Since Darwin, biologists have been struck by the extraordinary diversity of teleost fishes, particularly in contrast to their closest “living fossil” holostean relatives. Hypothesized drivers of teleost success include innovations in jaw mechanics, reproductive biology and, particularly at present, genomic architecture, yet all scenarios presuppose enhanced phenotypic diversification in teleosts. We test this key assumption by quantifying evolutionary rate and capacity for innovation in size and shape for the first 160 million y (Permian–Early Cretaceous) of evolution in neopterygian fishes (the more extensive clade containing teleosts and holosteans). We find that early teleosts do not show enhanced phenotypic evolution relative to holosteans. Instead, holostean rates and innovation often match or can even exceed those of stem-, crown-, and total-group teleosts, belying the living fossil reputation of their extant representatives. In addition, we find some evidence for heterogeneity within the teleost lineage. Although stem teleosts excel at discovering new body shapes, early crown-group taxa commonly display higher rates of shape evolution. However, the latter reflects low rates of shape evolution in stem teleosts relative to all other neopterygian taxa, rather than an exceptional feature of early crown teleosts. These results complement those emerging from studies of both extant teleosts as a whole and their sublineages, which generally fail to detect an association between genome duplication and significant shifts in rates of lineage diversification.

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Perceptions of a Collaborative Professional Learning Program: Seeing the “Bigger Picture”

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2019_persp-19-00041 ◽

2020 ◽

Vol 5 (1) ◽

pp. 290-303

Author(s):

P. Charlie Buckley ◽

Kimberly A. Murza ◽

Tami Cassel

Keyword(s):

Data Analysis ◽

Professional Learning ◽

Social Communication ◽

Special Educators ◽

Service Providers ◽

Integrative Approach ◽

Theory Approach ◽

Learning Program ◽

Speech Language Pathologists ◽

Related Service

Purpose The purpose of this study was to explore the perceptions of special education practitioners (i.e., speech-language pathologists, special educators, para-educators, and other related service providers) on their role as communication partners after participation in the Social Communication and Engagement Triad (Buckley et al., 2015 ) yearlong professional learning program. Method A qualitative approach using interviews and purposeful sampling was used. A total of 22 participants who completed participation in either Year 1 or Year 2 of the program were interviewed. Participants were speech-language pathologists, special educators, para-educators, and other related service providers. Using a grounded theory approach (Glaser & Strauss, 1967 ) to data analysis, open, axial, and selective coding procedures were followed. Results Three themes emerged from the data analysis and included engagement as the goal, role as a communication partner, and importance of collaboration. Conclusions Findings supported the notion that educators see the value of an integrative approach to service delivery, supporting students' social communication and engagement across the school day but also recognizing the challenges they face in making this a reality.

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