Search

Your search keyword '"Elderd, Bret"' showing total 232 results
Start Over Author "Elderd, Bret"
232 results on '"Elderd, Bret"'

3. A Note on Species Richness and the Variance of Epidemic Severity

Author

Shaffery, Peter, Elderd, Bret D., and Dukic, Vanja

Subjects
Quantitative Biology - Populations and Evolution
Abstract

The commonly observed negative correlation between the number of species in an ecological community and disease risk, typically referred to as "the dilution effect", has received a substantial amount of attention over the past decade. Attempts to test this relationship experimentally have revealed that, in addition to the mean disease risk decreasing with species number, so too does the variance of disease risk. This is referred to as the "variance reduction effect", and has received relatively little attention in the disease-diversity literature. Here, we set out to clarify and quantify some of these relationships in an idealized model of a randomly assembled multi-species community undergoing an epidemic. We specifically investigate the variance of the community disease reproductive ratio, a multi-species extension of the basic reproductive ratio R_0, for a family of random-parameter meta-community SIR models, and show how the variance of community $R_0$ varies depending on whether transmission is density or frequency-dependent. We finally outline areas of further research on how changes in variance affect transmission dynamics in other systems.

Published
2019

4. Global gene flow releases invasive plants from environmental constraints on genetic diversity

Author

Smith, Annabel L, Hodkinson, Trevor R, Villellas, Jesus, Catford, Jane A, Csergő, Anna Mária, Blomberg, Simone P, Crone, Elizabeth E, Ehrlén, Johan, Garcia, Maria B, Laine, Anna-Liisa, Roach, Deborah A, Salguero-Gómez, Roberto, Wardle, Glenda M, Childs, Dylan Z, Elderd, Bret D, Finn, Alain, Munné-Bosch, Sergi, Baudraz, Maude EA, Bódis, Judit, Brearley, Francis Q, Bucharova, Anna, Caruso, Christina M, Duncan, Richard P, Dwyer, John M, Gooden, Ben, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Moore, Joslin L, Morales, Melanie, Olsen, Siri Lie, Pärtel, Meelis, Petry, William K, Ramula, Satu, Rasmussen, Pil U, Enri, Simone Ravetto, Roeder, Anna, Roscher, Christiane, Saastamoinen, Marjo, Tack, Ayco JM, Töpper, Joachim Paul, Vose, Gregory E, Wandrag, Elizabeth M, Wingler, Astrid, and Buckley, Yvonne M

Subjects
Genetics, Demography, Gene Flow, Genetic Variation, Introduced Species, Phylogeny, Plantago, plant invasion, adaptation, global change, population genetics, demography
Abstract

When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.

Published
2020

39. Phenotypic plasticity masks range‐wide genetic differentiation for vegetative but not reproductive traits in a short‐lived plant

Author

Villellas, Jesus, primary, Ehrlén, Johan, additional, Crone, Elizabeth E., additional, Csergő, Anna Mária, additional, Garcia, Maria B., additional, Laine, Anna‐Liisa, additional, Roach, Deborah A., additional, Salguero‐Gómez, Roberto, additional, Wardle, Glenda M., additional, Childs, Dylan Z., additional, Elderd, Bret D., additional, Finn, Alain, additional, Munné‐Bosch, Sergi, additional, Bachelot, Benedicte, additional, Bódis, Judit, additional, Bucharova, Anna, additional, Caruso, Christina M., additional, Catford, Jane A., additional, Coghill, Matthew, additional, Compagnoni, Aldo, additional, Duncan, Richard P., additional, Dwyer, John M., additional, Ferguson, Aryana, additional, Fraser, Lauchlan H., additional, Griffoul, Emily, additional, Groenteman, Ronny, additional, Hamre, Liv Norunn, additional, Helm, Aveliina, additional, Kelly, Ruth, additional, Laanisto, Lauri, additional, Lonati, Michele, additional, Münzbergová, Zuzana, additional, Nuche, Paloma, additional, Olsen, Siri Lie, additional, Oprea, Adrian, additional, Pärtel, Meelis, additional, Petry, William K., additional, Ramula, Satu, additional, Rasmussen, Pil U., additional, Enri, Simone Ravetto, additional, Roeder, Anna, additional, Roscher, Christiane, additional, Schultz, Cheryl, additional, Skarpaas, Olav, additional, Smith, Annabel L., additional, Tack, Ayco J.M., additional, Töpper, Joachim Paul, additional, Vesk, Peter A., additional, Vose, Gregory E., additional, Wandrag, Elizabeth, additional, Wingler, Astrid, additional, and Buckley, Yvonne M., additional

Published
2021
Full Text
View/download PDF

40. Phenotypic plasticity masks range-wide genetic differentiation for vegetative but not reproductive traits in a short-lived plant

Author

Villellas, Jesus, Ehrlén, Johan, Crone, Elizabeth E., Csergő, Anna Maria, Garcia, Maria B., Laine, Anna-Liisa, Roach, Deborah A., Salguero-Gómez, Roberto, Wardle, Glenda M., Childs, Dylan Z., Elderd, Bret D., Finn, Alain, Munné-Bosch, Sergi, Bachelot, Benedicte, Bódis, Judit, Bucharova, Anna, Caruso, Christina M., Catford, Jane A., Coghill, Matthew, Compagnoni, Aldo, Duncan, Richard P., Dwyer, John M., Ferguson, Aryana, Fraser, Lauchlan H., Griffoul, Emily, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Münzbergová, Zuzana, Nuche, Paloma, Olsen, Siri Lie, Oprea, Adrian, Pärtel, Meelis, Petry, William K., Ramula, Satu, Rasmussen, Pil U., Ravetto Enri, Simone, Roeder, Anna, Roscher, Christiane, Schultz, Cheryl, Skarpaas, Olav, Smith, Annabel L., Tack, Ayco J. M., Töpper, Joachim Paul, Vesk, Peter A., Vose, Gregory E., Wandrag, Elizabeth, Wingler, Astrid, Buckley, Yvonne M., Villellas, Jesus, Ehrlén, Johan, Crone, Elizabeth E., Csergő, Anna Maria, Garcia, Maria B., Laine, Anna-Liisa, Roach, Deborah A., Salguero-Gómez, Roberto, Wardle, Glenda M., Childs, Dylan Z., Elderd, Bret D., Finn, Alain, Munné-Bosch, Sergi, Bachelot, Benedicte, Bódis, Judit, Bucharova, Anna, Caruso, Christina M., Catford, Jane A., Coghill, Matthew, Compagnoni, Aldo, Duncan, Richard P., Dwyer, John M., Ferguson, Aryana, Fraser, Lauchlan H., Griffoul, Emily, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Münzbergová, Zuzana, Nuche, Paloma, Olsen, Siri Lie, Oprea, Adrian, Pärtel, Meelis, Petry, William K., Ramula, Satu, Rasmussen, Pil U., Ravetto Enri, Simone, Roeder, Anna, Roscher, Christiane, Schultz, Cheryl, Skarpaas, Olav, Smith, Annabel L., Tack, Ayco J. M., Töpper, Joachim Paul, Vesk, Peter A., Vose, Gregory E., Wandrag, Elizabeth, Wingler, Astrid, and Buckley, Yvonne M.

Abstract

Genetic differentiation and phenotypic plasticity jointly shape intraspecific trait variation, but their roles differ among traits. In short-lived plants, reproductive traits may be more genetically determined due to their impact on fitness, whereas vegetative traits may show higher plasticity to buffer short-term perturbations. Combining a multi-treatment greenhouse experiment with observational field data throughout the range of a widespread short-lived herb, Plantago lanceolata, we (1) disentangled genetic and plastic responses of functional traits to a set of environmental drivers and (2) assessed how genetic differentiation and plasticity shape observational trait–environment relationships. Reproductive traits showed distinct genetic differentiation that largely determined observational patterns, but only when correcting traits for differences in biomass. Vegetative traits showed higher plasticity and opposite genetic and plastic responses, masking the genetic component underlying field-observed trait variation. Our study suggests that genetic differentiation may be inferred from observational data only for the traits most closely related to fitness.

Published
2021
Full Text
View/download PDF

43. Global gene flow releases invasive plants from environmental constraints on genetic diversity

Author

Smith, Annabel L., Hodkinson, Trevor R., Villellas, Jesus, Catford, Jane A., Csergo, Anna Maria, Blomberg, Simone P., Crone, Elizabeth E., Ehrlén, Johan, Garcia, Maria B., Laine, Anna-Liisa, Roach, Deborah A., Salguero-Gomez, Roberto, Wardle, Glenda M., Childs, Dylan Z., Elderd, Bret D., Finn, Alain, Munne-Bosch, Sergi, Baudraz, Maude E. A., Bodis, Judit, Brearley, Francis Q., Bucharova, Anna, Caruso, Christina M., Duncan, Richard P., Dwyerh, Johnm., Gooden, Ben, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Moore, Joslin L., Morales, Melanie, Olsen, Siri Lie, Partel, Meelis, Petry, William K., Ramula, Satu, Rasmussen, Pil U., Enri, Simone Ravetto, Roeder, Anna, Roscher, Christiane, Saastamoinen, Marjo, Tack, Ayco J. M., Topper, Joachim Paul, Vose, Gregory E., Wandrag, Elizabeth M., Wingler, Astrid, Buckley, Yvonne M., Smith, Annabel L., Hodkinson, Trevor R., Villellas, Jesus, Catford, Jane A., Csergo, Anna Maria, Blomberg, Simone P., Crone, Elizabeth E., Ehrlén, Johan, Garcia, Maria B., Laine, Anna-Liisa, Roach, Deborah A., Salguero-Gomez, Roberto, Wardle, Glenda M., Childs, Dylan Z., Elderd, Bret D., Finn, Alain, Munne-Bosch, Sergi, Baudraz, Maude E. A., Bodis, Judit, Brearley, Francis Q., Bucharova, Anna, Caruso, Christina M., Duncan, Richard P., Dwyerh, Johnm., Gooden, Ben, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Moore, Joslin L., Morales, Melanie, Olsen, Siri Lie, Partel, Meelis, Petry, William K., Ramula, Satu, Rasmussen, Pil U., Enri, Simone Ravetto, Roeder, Anna, Roscher, Christiane, Saastamoinen, Marjo, Tack, Ayco J. M., Topper, Joachim Paul, Vose, Gregory E., Wandrag, Elizabeth M., Wingler, Astrid, and Buckley, Yvonne M.

Abstract

When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata. Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.

Published
2020
Full Text
View/download PDF

44. Global gene flow releases invasive plants from environmental constraints on genetic diversity

Author

Science Foundation Ireland, European Research Council, European Commission, Generalitat de Catalunya, Ministerio de Economía y Competitividad (España), Ministry of Education and Research (Estonia), Ministry of Business, Innovation, and Employment (New Zealand), Academy of Finland, Smith, Annabel L., Hodkinson, Trevor R., Villellas, Jesús, Catford, Jane A., Csergó, Anna Mária, Blomberg, Simone P., Crone, Elisabeth E., Ehrlén, Johan, García, María B., Laine, Anna-Liisa, Roach, Deborah A., Salguero-Gómez, R., Wardle, Glenda M., Childs, Dylan Z., Elderd, Bret D., Finn, Alain, Munné-Bosch, Sergi, Baudraz, Maude E.A., Bódis, Judit, Brearley, Francis Q., Bucharova, Anna, Caruso, Christina M., Duncan, Richard P., Dwyer, John M., Gooden, Ben, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michael, Moore, Joslin L., Morales, Melanie, Olsen, Siri Lie, Pärtel, Meelis, Petry, William K., Ramula, Satu, Rasmussen, Pil U., Ravetto Enri, Simone, Roeder, Anna, Roscher, Christiane, Saastamoinen, Satu, Tack, Ayco J. M., Töpper, Joachim Paul, Vose, Gregory E., Wandrag, Elizabeth M., Wingler, Astrid, Buckley, Yvonne M., Science Foundation Ireland, European Research Council, European Commission, Generalitat de Catalunya, Ministerio de Economía y Competitividad (España), Ministry of Education and Research (Estonia), Ministry of Business, Innovation, and Employment (New Zealand), Academy of Finland, Smith, Annabel L., Hodkinson, Trevor R., Villellas, Jesús, Catford, Jane A., Csergó, Anna Mária, Blomberg, Simone P., Crone, Elisabeth E., Ehrlén, Johan, García, María B., Laine, Anna-Liisa, Roach, Deborah A., Salguero-Gómez, R., Wardle, Glenda M., Childs, Dylan Z., Elderd, Bret D., Finn, Alain, Munné-Bosch, Sergi, Baudraz, Maude E.A., Bódis, Judit, Brearley, Francis Q., Bucharova, Anna, Caruso, Christina M., Duncan, Richard P., Dwyer, John M., Gooden, Ben, Groenteman, Ronny, Hamre, Liv Norunn, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michael, Moore, Joslin L., Morales, Melanie, Olsen, Siri Lie, Pärtel, Meelis, Petry, William K., Ramula, Satu, Rasmussen, Pil U., Ravetto Enri, Simone, Roeder, Anna, Roscher, Christiane, Saastamoinen, Satu, Tack, Ayco J. M., Töpper, Joachim Paul, Vose, Gregory E., Wandrag, Elizabeth M., Wingler, Astrid, and Buckley, Yvonne M.

Abstract

When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata. Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.

Published
2020

45. Global gene flow releases invasive plants from environmental constraints on genetic diversity

Author

Smith, Annabel, Hodkinson, Trevor, Villellas, Jesus, Catford, Jane, Csergo, Anna, Blomberg, Simone, Crone, Elizabeth, Ehrlen, Johan, Garcia, Maria, Laine, Anna, Roach, Deborah, Salguero-Gomez, Roberto, Wardle, Glenda, Childs, Dylan, Elderd, Bret, Finn, Alain, Munne-Bosch, Sergi, Baudraz, Maude, Bodis, Judit, Brearley, Francis, Bucharova, Anna, Caruso, Christina, Duncan, Richard, Dwyer, John, Gooden, Ben, Groenteman, Ronny, Hamre, Liv, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Moore, Joslin, Morales, Melanie, Olsen, Siri, Partel, Meelis, Petry, William, Ramula, Satu, Rasmussen, Pil, Enri, Simone, Roeder, Anna, Roscher, Christiane, Saastamoinen, Marjo, Tack, Ayco, Topper, Joachim, Vose, Gregory, Wandrag, Elizabeth, Wingler, Astrid, Buckley, Yvonne, Smith, Annabel, Hodkinson, Trevor, Villellas, Jesus, Catford, Jane, Csergo, Anna, Blomberg, Simone, Crone, Elizabeth, Ehrlen, Johan, Garcia, Maria, Laine, Anna, Roach, Deborah, Salguero-Gomez, Roberto, Wardle, Glenda, Childs, Dylan, Elderd, Bret, Finn, Alain, Munne-Bosch, Sergi, Baudraz, Maude, Bodis, Judit, Brearley, Francis, Bucharova, Anna, Caruso, Christina, Duncan, Richard, Dwyer, John, Gooden, Ben, Groenteman, Ronny, Hamre, Liv, Helm, Aveliina, Kelly, Ruth, Laanisto, Lauri, Lonati, Michele, Moore, Joslin, Morales, Melanie, Olsen, Siri, Partel, Meelis, Petry, William, Ramula, Satu, Rasmussen, Pil, Enri, Simone, Roeder, Anna, Roscher, Christiane, Saastamoinen, Marjo, Tack, Ayco, Topper, Joachim, Vose, Gregory, Wandrag, Elizabeth, Wingler, Astrid, and Buckley, Yvonne

Abstract

© 2020 National Academy of Sciences. All rights reserved. When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata. Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.

Published
2020

46. Genetic differentiation can be predicted from observational data for reproductive but not vegetative traits in a widespread short-lived plant

Author

Villellas, Jesus, primary, Ehrlén, Johan, additional, Crone, Elizabeth, additional, Csergő, Anna, additional, Garcia, Maria, additional, Laine, Anna-Liisa, additional, Roach, Deborah, additional, Salguero-Gomez, Roberto, additional, Wardle, Glenda, additional, Childs, Dylan, additional, Elderd, Bret, additional, Finn, Alain, additional, Munne-Bosch, Sergi, additional, Bachelot, Benedicte, additional, Bódis, Judit, additional, Bucharova, Anna, additional, Caruso, Christina, additional, Catford, Jane, additional, Coghill, Matthew, additional, Compagnoni, Aldo, additional, Duncan, Richard, additional, Dwyer, John, additional, Ferguson, Aryana, additional, Fraser, Lauchlan, additional, Griffoul, Emily, additional, Groenteman, Ronny, additional, Hamre, Liv Norunn, additional, Helm, Aveliina, additional, Kelly, Ruth, additional, Laanisto, Lauri, additional, Lonati, Michele, additional, Munzbergova, Zuzana, additional, Nuche, Paloma, additional, Olsen, Siri, additional, Oprea, Adrian, additional, Partel, Meelis, additional, Petry, William, additional, Ramula, Satu, additional, Rasmussen, Pil, additional, Enri, Simone, additional, Roeder, Anna, additional, Roscher, Christiane, additional, Schultz, Cheryl, additional, Skarpaas, Olav, additional, Smith, Annabel, additional, Tack, Ayco, additional, Töpper, Joachim, additional, Vesk, Peter, additional, Vose, Gregory, additional, Wandrag, Elizabeth, additional, Wingler, Astrid, additional, and Buckley, Yvonne, additional

Published
2021
Full Text
View/download PDF

49. Social constraints on the onset of incubation in a neotropical parrot: a nestbox addition experiment

Author

Beissinger, Steven R., Tygielski, Susanne, and Elderd, Bret

Subjects
Parrots -- Behavior, Eggs -- Incubation, Birds -- Eggs and nests, Zoology and wildlife conservation
Abstract

The impact of early onset of incubation was examined to determine whether it serves to protect eggs from dangers imposed by conspecifics in the green-rumped parrotlet, Forpus passerinus. Nestboxes with eggs were installed and observed for egg destruction and nest-site takeovers. Findings showed that egg destruction at the nestboxes occurred during daylight and all mortality was caused by green-rumped parrotlets. Lone males never caused destruction, although they frequently visited the nestboxes. No significant differences were found in the frequency of visitations of lone males.

Published
1998

Catalog

Books, media, physical & digital resources
See catalog results