Fire as a fundamental ecological process: Research advances and frontiers

© 2020 The Authors. Journal of Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society Fire is a powerful ecological and evolutionary force that regulates organismal traits, population sizes, species interactions, community composition, carbon and nutrient cycling and ecosystem function. It also presents a rapidly growing societal challenge, due to both increasingly destructive wildfires and fire exclusion in fire-dependent ecosystems. As an ecological process, fire integrates complex feedbacks among biological, social and geophysical processes, requiring coordination across several fields and scales of study. Here, we describe the diversity of ways in which fire operates as a fundamental ecological and evolutionary process on Earth. We explore research priorities in six categories of fire ecology: (a) characteristics of fire regimes, (b) changing fire regimes, (c) fire effects on above-ground ecology, (d) fire effects on below-ground ecology, (e) fire behaviour and (f) fire ecology modelling. We identify three emergent themes: the need to study fire across temporal scales, to assess the mechanisms underlying a variety of ecological feedbacks involving fire and to improve representation of fire in a range of modelling contexts. Synthesis: As fire regimes and our relationships with fire continue to change, prioritizing these research areas will facilitate understanding of the ecological causes and consequences of future fires and rethinking fire management alternatives

Fire as a fundamental ecological process: Research advances and frontiers

© 2020 The Authors.Fire is a powerful ecological and evolutionary force that regulates organismal traits, population sizes, species interactions, community composition, carbon and nutrient cycling and ecosystem function. It also presents a rapidly growing societal challenge, due to both increasingly destructive wildfires and fire exclusion in fire‐dependent ecosystems. As an ecological process, fire integrates complex feedbacks among biological, social and geophysical processes, requiring coordination across several fields and scales of study. Here, we describe the diversity of ways in which fire operates as a fundamental ecological and evolutionary process on Earth. We explore research priorities in six categories of fire ecology: (a) characteristics of fire regimes, (b) changing fire regimes, (c) fire effects on above‐ground ecology, (d) fire effects on below‐ground ecology, (e) fire behaviour and (f) fire ecology modelling. We identify three emergent themes: the need to study fire across temporal scales, to assess the mechanisms underlying a variety of ecological feedbacks involving fire and to improve representation of fire in a range of modelling contexts. Synthesis: As fire regimes and our relationships with fire continue to change, prioritizing these research areas will facilitate understanding of the ecological causes and consequences of future fires and rethinking fire management alternatives.Support was provided by NSF‐DEB‐1743681 to K.K.M. and A.J.T. We thank Shalin Hai‐Jew for helpful discussion of the survey and qualitative methods.Peer reviewe

Reconstructing the feeding ecology of Cambrian sponge reefs: The case for active suspension feeding in Archaeocyatha

Sponge-grade Archaeocyatha were early Cambrian biomineralizing metazoans that constructed reefs globally. Despite decades of research, many facets of archaeocyath palaeobiology remain unclear, making it difficult to reconstruct the palaeoecology of Cambrian reef ecosystems. Of specific interest is how these organisms fed; previous experimental studies have suggested that archaeocyaths functioned as passive suspension feeders relying on ambient currents to transport nutrient-rich water into their central cavities. Here, we test this hypothesis using computational fluid dynamics (CFD) simulations of digital models of select archaeocyath species. Our results demonstrate that, given a range of plausible current velocities, there was very little fluid circulation through the skeleton, suggesting obligate passive suspension feeding was unlikely. Comparing our simulation data with exhalent velocities collected from extant sponges, we infer an active suspension feeding lifestyle for archaeocyaths. The combination of active suspension feeding and biomineralization in Archaeocyatha may have facilitated the creation of modern metazoan reef ecosystems.<p>Funding provided by: Alexander von Humboldt Foundation<br>Crossref Funder Registry ID: https://ror.org/012kf4317<br>Award Number: </p><p>Funding provided by: Natural Sciences and Engineering Research Council<br>Crossref Funder Registry ID: https://ror.org/01h531d29<br>Award Number: RGPIN 435402</p><p>Funding provided by: National Science Foundation<br>Crossref Funder Registry ID: https://ror.org/021nxhr62<br>Award Number: NSF-NERC EAR-2007928</p><p>Funding provided by: Natural Environment Research Council<br>Crossref Funder Registry ID: https://ror.org/02b5d8509<br>Award Number: NE/V010859/2</p><p>Funding provided by: University of Toronto<br>Crossref Funder Registry ID: https://ror.org/03dbr7087<br>Award Number: </p><p>COMSOL Multiphysics computational fluid dynamics simulation solution files. Simulations were solved, meshes subsequently cleared (parameters remain). Necessary 3D geometry files are also provided. </p&gt

Reconstructing the feeding ecology of Cambrian sponge reefs: the case for active suspension feeding in Archaeocyatha

Sponge-grade Archaeocyatha were early Cambrian biomineralizing metazoans that constructed reefs globally. Despite decades of research, many facets of archaeocyath palaeobiology remain unclear, making it difficult to reconstruct the palaeoecology of Cambrian reef ecosystems. Of specific interest is how these organisms fed; previous experimental studies have suggested that archaeocyaths functioned as passive suspension feeders relying on ambient currents to transport nutrient-rich water into their central cavities. Here, we test this hypothesis using computational fluid dynamics (CFD) simulations of digital models of select archaeocyath species. Our results demonstrate that, given a range of plausible current velocities, there was very little fluid circulation through the skeleton, suggesting obligate passive suspension feeding was unlikely. Comparing our simulation data with exhalent velocities collected from extant sponges, we infer an active suspension feeding lifestyle for archaeocyaths. The combination of active suspension feeding and biomineralization in Archaeocyatha may have facilitated the creation of modern metazoan reef ecosystems. The attached file is the published version of the article.Copyright © 2023 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.NHM Repositor

Not just a checkbox: A qualitative study of the resident scholarly experience.

OBJECTIVES: Scholarship is a requirement of residency training; however, the scholarly productivity of trainees is highly variable. The purpose of this study was to explore the perspectives of residents who have been highly productive in scholarship. METHODS: We performed a qualitative study using a constructivist-interpretivist paradigm and conducted semistructured interviews at seven Accreditation Council for Graduate Medical Education-accredited emergency medicine residency programs in the United States. We included sites of diverse locations and training formats (PGY-1 to -4 vs. PGY-1 to -3). Program leadership identified residents with high levels of scholarly productivity at their institutions. We used purposive sampling to seek out residents with diversity in gender and PGY level. Two researchers independently performed a thematic analysis of interview transcripts. Discrepancies were resolved through in-depth discussion and negotiated consensus. RESULTS: We invited 14 residents and all consented to be interviewed. Residents felt scholarship enhanced their knowledge and skills, grew collaborative networks, and provided personal fulfillment and external rewards. Scholarship positively impacted their careers by focusing their professional interests and informing career decisions. Participants identified individual and institutional facilitators of success including personal prior knowledge and skills, project management skills, mindset, protected time, mentorship, and leadership support. Challenges to conducting scholarship included lack of time, expertise, and resources. Participants acknowledged that participating in scholarly activities was hard work and recommended that residents seek out quality mentorship, work on projects that they are passionate, start early, and be persistent in their efforts. Participants advice to faculty supporting resident scholarship included recommendations to allow resident autonomy of projects, provide scholarly opportunities, and be responsive to trainee needs. CONCLUSIONS: Participants in this study highlighted benefits of participating in scholarly activity as well as challenges and strategies for success. These results can inform residencies seeking to enhance the scholarly experience of trainees

The Capsid Proteins of a Large, Icosahedral dsDNA Virus

International audienceChilo iridescent virus (CIV) is a large (not, vert, similar 1850 Å diameter) insect virus with an icosahedral, T = 147 capsid, a double-stranded DNA (dsDNA) genome, and an internal lipid membrane. The structure of CIV was determined to 13 Å resolution by means of cryoelectron microscopy (cryoEM) and three-dimensional image reconstruction. A homology model of P50, the CIV major capsid protein (MCP), was built based on its amino acid sequence and the structure of the homologous Paramecium bursaria chlorella virus 1 Vp54 MCP. This model was fitted into the cryoEM density for each of the 25 trimeric CIV capsomers per icosahedral asymmetric unit. A difference map, in which the fitted CIV MCP capsomers were subtracted from the CIV cryoEM reconstruction, showed that there are at least three different types of minor capsid proteins associated with the capsomers outside the lipid membrane. “Finger” proteins are situated at many, but not all, of the spaces between three adjacent capsomers within each trisymmetron, and “zip” proteins are situated between sets of three adjacent capsomers at the boundary between neighboring trisymmetrons and pentasymmetrons. Based on the results of segmentation and density correlations, there are at least eight finger proteins and three dimeric and two monomeric zip proteins in one asymmetric unit of the CIV capsid. These minor proteins appear to stabilize the virus by acting as intercapsomer cross-links. One transmembrane “anchor” protein per icosahedral asymmetric unit, which extends from beneath one of the capsomers in the pentasymmetron to the internal leaflet of the lipid membrane, may provide additional stabilization for the capsid. These results are consistent with the observations for other large, icosahedral dsDNA viruses that also utilize minor capsid proteins for stabilization and for determining their assembly

“Not just a checkbox”: A qualitative study of the resident scholarly experience

ObjectivesScholarship is a requirement of residency training; however, the scholarly productivity of trainees is highly variable. The purpose of this study was to explore the perspectives of residents who have been highly productive in scholarship.MethodsWe performed a qualitative study using a constructivist–interpretivist paradigm and conducted semistructured interviews at seven Accreditation Council for Graduate Medical Education–accredited emergency medicine residency programs in the United States. We included sites of diverse locations and training formats (PGY-1 to -4 vs. PGY-1 to -3). Program leadership identified residents with high levels of scholarly productivity at their institutions. We used purposive sampling to seek out residents with diversity in gender and PGY level. Two researchers independently performed a thematic analysis of interview transcripts. Discrepancies were resolved through in-depth discussion and negotiated consensus.ResultsWe invited 14 residents and all consented to be interviewed. Residents felt scholarship enhanced their knowledge and skills, grew collaborative networks, and provided personal fulfillment and external rewards. Scholarship positively impacted their careers by focusing their professional interests and informing career decisions. Participants identified individual and institutional facilitators of success including personal prior knowledge and skills, project management skills, mindset, protected time, mentorship, and leadership support. Challenges to conducting scholarship included lack of time, expertise, and resources. Participants acknowledged that participating in scholarly activities was hard work and recommended that residents seek out quality mentorship, work on projects that they are passionate, start early, and be persistent in their efforts. Participants’ advice to faculty supporting resident scholarship included recommendations to allow resident autonomy of projects, provide scholarly opportunities, and be responsive to trainee needs.ConclusionsParticipants in this study highlighted benefits of participating in scholarly activity as well as challenges and strategies for success. These results can inform residencies seeking to enhance the scholarly experience of trainees.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/175416/1/aet210824.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/175416/2/aet210824_am.pd