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2. Inferring Phenotypic Trait Evolution on Large Trees With Many Incomplete Measurements

Author

Hassler, Gabriel, Tolkoff, Max R, Allen, William L, Ho, Lam Si Tung, Lemey, Philippe, and Suchard, Marc A

Subjects
Economics, Statistics, Econometrics, Mathematical Sciences, Bioengineering, 1.4 Methodologies and measurements, Aetiology, 2.5 Research design and methodologies (aetiology), Underpinning research, Generic health relevance, Bayesian inference, Matrix-normal, Missing data, Phylogenetics, matrix-normal, missing data, phylogenetics, stat.ME, stat.CO, Demography, Statistics & Probability
Abstract

Comparative biologists are often interested in inferring covariation between multiple biological traits sampled across numerous related taxa. To properly study these relationships, we must control for the shared evolutionary history of the taxa to avoid spurious inference. An additional challenge arises as obtaining a full suite of measurements becomes increasingly difficult with increasing taxa. This generally necessitates data imputation or integration, and existing control techniques typically scale poorly as the number of taxa increases. We propose an inference technique that integrates out missing measurements analytically and scales linearly with the number of taxa by using a post-order traversal algorithm under a multivariate Brownian diffusion (MBD) model to characterize trait evolution. We further exploit this technique to extend the MBD model to account for sampling error or non-heritable residual variance. We test these methods to examine mammalian life history traits, prokaryotic genomic and phenotypic traits, and HIV infection traits. We find computational efficiency increases that top two orders-of-magnitude over current best practices. While we focus on the utility of this algorithm in phylogenetic comparative methods, our approach generalizes to solve long-standing challenges in computing the likelihood for matrix-normal and multivariate normal distributions with missing data at scale.

Published
2022

3. Principled, practical, flexible, fast: a new approach to phylogenetic factor analysis

Author

Hassler, Gabriel W., Gallone, Brigida, Aristide, Leandro, Allen, William L., Tolkoff, Max R., Holbrook, Andrew J., Baele, Guy, Lemey, Philippe, and Suchard, Marc A.

Subjects
Quantitative Biology - Populations and Evolution, Statistics - Applications, Statistics - Methodology
Abstract

Biological phenotypes are products of complex evolutionary processes in which selective forces influence multiple biological trait measurements in unknown ways. Phylogenetic factor analysis disentangles these relationships across the evolutionary history of a group of organisms. Scientists seeking to employ this modeling framework confront numerous modeling and implementation decisions, the details of which pose computational and replicability challenges. General and impactful community employment requires a data scientific analysis plan that balances flexibility, speed and ease of use, while minimizing model and algorithm tuning. Even in the presence of non-trivial phylogenetic model constraints, we show that one may analytically address latent factor uncertainty in a way that (a) aids model flexibility, (b) accelerates computation (by as much as 500-fold) and (c) decreases required tuning. We further present practical guidance on inference and modeling decisions as well as diagnosing and solving common problems in these analyses. We codify this analysis plan in an automated pipeline that distills the potentially overwhelming array of modeling decisions into a small handful of (typically binary) choices. We demonstrate the utility of these methods and analysis plan in four real-world problems of varying scales., Comment: 27 pages, 7 figures, 1 table

Published
2021

4. Inferring phenotypic trait evolution on large trees with many incomplete measurements

Author

Hassler, Gabriel, Tolkoff, Max R., Allen, William L., Ho, Lam Si Tung, Lemey, Philippe, and Suchard, Marc A.

Subjects
Statistics - Methodology, Statistics - Computation
Abstract

Comparative biologists are often interested in inferring covariation between multiple biological traits sampled across numerous related taxa. To properly study these relationships, we must control for the shared evolutionary history of the taxa to avoid spurious inference. Existing control techniques almost universally scale poorly as the number of taxa increases. An additional challenge arises as obtaining a full suite of measurements becomes increasingly difficult with increasing taxa. This typically necessitates data imputation or integration that further exacerbates scalability. We propose an inference technique that integrates out missing measurements analytically and scales linearly with the number of taxa by using a post-order traversal algorithm under a multivariate Brownian diffusion (MBD) model to characterize trait evolution. We further exploit this technique to extend the MBD model to account for sampling error or non-heritable residual variance. We test these methods to examine mammalian life history traits, prokaryotic genomic and phenotypic traits, and HIV infection traits. We find computational efficiency increases that top two orders-of-magnitude over current best practices. While we focus on the utility of this algorithm in phylogenetic comparative methods, our approach generalizes to solve long-standing challenges in computing the likelihood for matrix-normal and multivariate normal distributions with missing data at scale., Comment: 29 pages, 7 figures, 2 tables, 3 supplementary sections

Published
2019

5. Messaging migration : media agenda-setting, immigration attitudes, and the effects of evidence on perceptions and policy preferences

Author

Allen, William L. and Tilley, James

Subjects
325.41, Emigration and immigration
Abstract

How do messages impact what people think? Although this broad question speaks to current debates about the role of information in politics, variations of it have appeared throughout political science. My approach draws upon political communication, psychology, and linguistics to demonstrate how information relates to attitudes, perceptions, and policy preferences. Across four separate studies that use the issue of immigration in the British case, I address several sub-questions. First, how has the British press-itself a key messenger of political information-portrayed immigration and immigrants over several decades? Applying corpus linguistic methods, I find press coverage about immigration has both increased and been characterised by several sub-agendas. Second, how have these messages at the word-level related to changes in public concern about immigration? Using time series models, I show how specific dimensions of immigration-its sociocultural, geographic, and numerical aspects-and not overall levels of coverage are related to aggregate public concern. These two studies collectively demonstrate how the agenda-setting power of print media is likely more subtle and delimited than commonly expected. In the third study, I focus on the individual-level impacts of messages. Which qualities of immigrants matter more for public attitudes? Findings from a nationally-representative conjoint survey experiment demonstrate how the British public places greater importance on skill level and language fluency when evaluating individual immigrants. Finally, I broaden my view of messages to include different types of supporting evidence. Do arguments citing numerical or narrative evidence impact public perceptions and policy preferences? A second nationally-representative survey experiment shows how positive messages about immigrants featuring numerical or narrative supporting evidence can positively change perceptions, especially among people who would be expected to hold more negative views. But, the presence of extra information neither raises perceptions more than similarly positive messages lacking evidence, nor influences policy preferences.

Published
2019

7. Antarctica : a new age of exploration. National Geographic. Gilbert M. Grosvenor, Chairman ... Produced by National Geographic Maps for National Geographic Magazine, National Geographic: William L. Allen, ed. in chief ; Allen Carroll, chief cartograper. Washington, D.C. February 2002. Copyright 2002 National Geographic Society. Printed December, 2001. (insets) Surface elevation. (with) Ice sheet thickness. (with) Ice flow velocity. (with) Sea ice movement and wind flow. (on verso: Relief map of Antarctica).

Author

Allen, William L., Carroll, Allen, and National Geographic Society (U.S.). Cartographic Division.

Subjects
Mountains, Rivers
Abstract

2 color maps of Antarctica on 1 sheet, both sides. Relief shown by spot heights and shading. Azimuthal equidistant projection. Depth shown by bathymetric tints. Map showing research stations and automatic weather stations. Includes location map, population density and many historical notes concerning the discovery and exploration of the continent. On verso: Relief map of Antarctica, text, cross section and photos.

Published
2002

8. Proceedings of the Second Annual Deep Brain Stimulation Think Tank: What's in the Pipeline

Author

Gunduz, Aysegul, Morita, Hokuto, Rossi, P Justin, Allen, William L, Alterman, Ron L, Bronte-Stewart, Helen, Butson, Christopher R, Charles, David, Deckers, Sjaak, de Hemptinne, Coralie, DeLong, Mahlon, Dougherty, Darin, Ellrich, Jens, Foote, Kelly D, Giordano, James, Goodman, Wayne, Greenberg, Benjamin D, Greene, David, Gross, Robert, Judy, Jack W, Karst, Edward, Kent, Alexander, Kopell, Brian, Lang, Anthony, Lozano, Andres, Lungu, Codrin, Lyons, Kelly E, Machado, Andre, Martens, Hubert, McIntyre, Cameron, Min, Hoon-Ki, Neimat, Joseph, Ostrem, Jill, Pannu, Sat, Ponce, Francisco, Pouratian, Nader, Reymers, Donnie, Schrock, Lauren, Sheth, Sameer, Shih, Ludy, Stanslaski, Scott, Steinke, G Karl, Stypulkowski, Paul, Tröster, Alexander I, Verhagen, Leo, Walker, Harrison, and Okun, Michael S

Subjects
Biomedical and Clinical Sciences, Biological Psychology, Clinical Sciences, Neurosciences, Psychology, Assistive Technology, Bioengineering, Mental Health, Parkinson's Disease, Brain Disorders, Rehabilitation, Neurodegenerative, Neurological, Animals, Brain, Deep Brain Stimulation, Humans, International Cooperation, Parkinson Disease, Tourette Syndrome, deep brain stimulation, Movement disorders, Neuroethics, Electrophysiology, neurotechnology, Cognitive Sciences, Neurology & Neurosurgery, Clinical sciences, Biological psychology
Abstract

The proceedings of the 2nd Annual Deep Brain Stimulation Think Tank summarize the most contemporary clinical, electrophysiological, and computational work on DBS for the treatment of neurological and neuropsychiatric disease and represent the insights of a unique multidisciplinary ensemble of expert neurologists, neurosurgeons, neuropsychologists, psychiatrists, scientists, engineers and members of industry. Presentations and discussions covered a broad range of topics, including advocacy for DBS, improving clinical outcomes, innovations in computational models of DBS, understanding of the neurophysiology of Parkinson's disease (PD) and Tourette syndrome (TS) and evolving sensor and device technologies.

Published
2015

11. The evolution and ecology of multiple antipredator defences

Author

Kikuchi, David W., Allen, William L., Arbuckle, Kevin, Aubier, Thomas G., Briolat, Emmanuelle S., Burdfield‐Steel, Emily R., Cheney, Karen L., Daňková, Klára, Elias, Marianne, Hämäläinen, Liisa, Herberstein, Marie E., Hossie, Thomas J., Joron, Mathieu, Kunte, Krushnamegh, Leavell, Brian C., Lindstedt, Carita, Lorioux‐Chevalier, Ugo, McClure, Melanie, McLellan, Callum F., Medina, Iliana, Nawge, Viraj, Páez, Erika, Pal, Arka, Pekár, Stano, Penacchio, Olivier, Raška, Jan, Reader, Tom, Rojas, Bibiana, Rönkä, Katja H., Rößler, Daniela C., Rowe, Candy, Rowland, Hannah M., Roy, Arlety, Schaal, Kaitlin A., Sherratt, Thomas N., Skelhorn, John, Smart, Hannah R., Stankowich, Ted, Stefan, Amanda M., Summers, Kyle, Taylor, Christopher H., Thorogood, Rose, Umbers, Kate, Winters, Anne E., Yeager, Justin, and Exnerová, Alice

Subjects
saaliseläimet, vuorovaikutus, predation sequence, defence portfolio, antergy, synergy, defence syndrome, secondary defences, saalistus, eläintiede, trade-offs, intraspecific variation, antergy , defence portfolio , defence syndrome , intraspecific variation , predation sequence , predator cognition, secondary defences , synergy, petoeläimet, synergia, puolustus, predator cognition
Abstract

Prey seldom rely on a single type of antipredator defence, often using multiple defences to avoid predation. In many cases, selection in different contexts may favour the evolution of multiple defences in a prey. However, a prey may use multiple defences to protect itself during a single predator encounter. Such “defence portfolios” that defend prey against a single instance of predation are distributed across and within successive stages of the predation sequence (encounter, detection, identification, approach (attack), subjugation and consumption). We contend that at present, our understanding of defence portfolio evolution is incomplete, and seen from the fragmentary perspective of specific sensory systems (e.g., visual) or specific types of defences (especially aposematism). In this review, we aim to build a comprehensive framework for conceptualizing the evolution of multiple prey defences, beginning with hypotheses for the evolution of multiple defences in general, and defence portfolios in particular. We then examine idealized models of resource trade-offs and functional interactions between traits, along with evidence supporting them. We find that defence portfolios are constrained by resource allocation to other aspects of life history, as well as functional incompatibilities between different defences. We also find that selection is likely to favour combinations of defences that have synergistic effects on predator behaviour and prey survival. Next, we examine specific aspects of prey ecology, genetics and development, and predator cognition that modify the predictions of current hypotheses or introduce competing hypotheses. We outline schema for gathering data on the distribution of prey defences across species and geography, determining how multiple defences are produced, and testing the proximate mechanisms by which multiple prey defences impact predator behaviour. Adopting these approaches will strengthen our understanding of multiple defensive strategies. peerReviewed

Published
2023

20. Shock Mobilities During Moments of Acute Uncertainty

Author

Xiang, Biao, Allen, William L., Khosravi, Shahram, Kringelbach, Hélène Neveu, Ortiga, Yasmin Y., Liao, Karen Anne S., Cuéllar, Jorge E., Momen, Lamea, Deshingkar, Priya, Naik, Mukta, Xiang, Biao, Allen, William L., Khosravi, Shahram, Kringelbach, Hélène Neveu, Ortiga, Yasmin Y., Liao, Karen Anne S., Cuéllar, Jorge E., Momen, Lamea, Deshingkar, Priya, and Naik, Mukta

Abstract

The COVID-19 pandemic and interventions addressing it raise important questions about human mobility that have geopolitical implications. This forum uses mobility and immobility during the pandemic as lenses onto the ways that routinised state power reacts to acute uncertainties, as well as how these reactions impact politics and societies. Specifically, we propose the concept of “shock mobility” as migratory routines radically reconfigured: emergency flights from epicentres, mass repatriations, lockdowns, quarantines. Patterns of shock mobility and immobility are not new categories of movement, but rather are significant alterations to the timing, duration, intensity, and relations among existing movements. Many of these alterations have been induced by governments’ reactions to the pandemic in both migrant-sending and receiving contexts, which can be especially consequential for migrants in and from the Global South. Our interventions explore these processes by highlighting experiences of Afghans and Kurds along Iran’s borders, Western Africans in Europe, Filipino workers, irregular Bangladeshis in Qatar, Central Americans travelling northwards via Mexico, and rural-urban migrants in India. In total, we argue that tracing shocks’ dynamics in a comparative manner provides an analytical means for assessing the long-term implications of the pandemic, building theories about how and why any particular post-crisis world emerges as it does, and paving the way for future empirical work.

Published
2022
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21. Cascading Activation Revisited: How Audiences Contribute to News Agendas Using Social Media

Author

Landis, Benjamin Till, Allen, William L., Landis, Benjamin Till, and Allen, William L.

Abstract

Social media have become conduits through which audiences can challenge elites in media and politics. Recent updates to cascading activation, originally developed to explain how frames flowing from powerful figures gain public dominance, give greater theoretical scope for audiences to exert influence. Yet empirical understanding of how and in what circumstances this happens with respect to agenda-setting - another core media effect - is not well-developed, especially given the affordances of digital technologies. We address this gap by connecting theorization on cascades to developments in intermedia agenda-setting. Specifically, we analyze the dynamics surrounding the perceived reluctance by ARD-aktuell, the newsroom of Germany's public broadcasting consortium, to use its prime-time broadcast "Tagesschau" to report the arrest of a refugee accused of murdering a German woman in December 2016. By presenting finely grained timelines linking content analysis of 5,409 Facebook comments with Tagesschau editorial responses and parallel media coverage of this event, we contribute further conditions under which audience-informed cascades may occur: notably, when publicly funded news organizations are involved, and the issue at stake invokes both domestic and international aspects which sustain disagreement.

Published
2022

32. Fast life history traits promote invasion success in amphibians and reptiles

Author

Allen, William L., Street, Sally E., and Capellini, Isabella

Subjects
Letter, Population Dynamics, biological invasions, comparative analyses, Reptiles, life history theory, reptiles, invasive species, transient dynamics, Amphibians, population growth, population dynamics, Animals, Letters, invasion biology, Introduced Species, Animal Distribution, Life History Traits, Phylogeny, Ecology, Evolution, Behavior and Systematics
Abstract

Competing theoretical models make different predictions on which life history strategies facilitate growth of small populations. While ‘fast’ strategies allow for rapid increase in population size and limit vulnerability to stochastic events, ‘slow’ strategies and bet‐hedging may reduce variance in vital rates in response to stochasticity. We test these predictions using biological invasions since founder alien populations start small, compiling the largest dataset yet of global herpetological introductions and life history traits. Using state‐of‐the‐art phylogenetic comparative methods, we show that successful invaders have fast traits, such as large and frequent clutches, at both establishment and spread stages. These results, together with recent findings in mammals and plants, support ‘fast advantage’ models and the importance of high potential population growth rate. Conversely, successful alien birds are bet‐hedgers. We propose that transient population dynamics and differences in longevity and behavioural flexibility can help reconcile apparently contrasting results across terrestrial vertebrate classes.

Published
2017

35. The role of life history traits in mammalian invasion success

Author

Capellini, Isabella, Baker, Joanna, Allen, William L., Street, Sally E., Venditti, Chris, and Wiens, John

Subjects
Mammals, Invasion pathway, Range expansion, Life history theory, Alien species, Biological invasions, Colonisation success, Phylogeny, Ecology, Evolution, Behavior and Systematics, Demography, Propagule pressure
Abstract

Why some organisms become invasive when introduced into novel regions while others fail to even establish is a fundamental question in ecology. Barriers to success are expected to filter species at each stage along the invasion pathway. No study to date, however, has investigated how species traits associate with success from introduction to spread at a large spatial scale in any group. Using the largest data set of mammalian introductions at the global scale and recently developed phylogenetic comparative methods, we show that human-mediated introductions considerably bias which species have the opportunity to become invasive, as highly productive mammals with longer reproductive lifespans are far more likely to be introduced. Subsequently, greater reproductive output and higher introduction effort are associated with success at both the establishment and spread stages. High productivity thus supports population growth and invasion success, with barriers at each invasion stage filtering species with progressively greater fecundity.

Published
2015

36. Multiple opportunities arise from multiple color defense strategies: a comment on Postema et al.

Author

Kelley, Jennifer L and Allen, William L

Subjects
*COLOR, *ANIMAL coloration
Abstract

For example, individuals use their body coloration to avoid detection and recognition, startle predators, signal unpalatability, and divert predator attacks ([4]). [3] review provides a novel and refreshing perspective on the conflicting selection pressures that shape animal coloration, and the multifunctional strategies that have evolved as a result. Thus, the categorization of defensive coloration strategies provides a unique opportunity to re-examine the link between coloration and behavioral defense in the context of function(s) and mechanism(s). [Extracted from the article]

Published
2023
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38. Book reviews

Author

Allen, William L., Ruf, Henry L., Jalloh, Chernor M., Donnelly, John, Gill, Jerry H., Barrett, Lee, Hall, Ronald L., and Kluback, William

Published
1987
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40. Experimental evidence that primate trichromacy is well suited for detecting primate social colour signals.

Author

Chihiro Hiramatsu, Melin, Amanda D., Allen, William L., Dubuc, Constance, and Higham, James P.

Subjects
COLOR vision testing, PRIMATES, PHOTORECEPTORS, DIGITAL images, ANIMAL coloration, SPECTRAL reflectance
Abstract

Primate trichromatic colour vision has been hypothesized to be well tuned for detecting variation in facial coloration, which could be due to selection on either signal wavelengths or the sensitivities of the photoreceptors themselves. We provide one of the first empirical tests of this idea by asking whether, when compared with other visual systems, the information obtained through primate trichromatic vision confers an improved ability to detect the changes in facial colour that female macaque monkeys exhibit when they are proceptive. We presented pairs of digital images of faces of the same monkey to human observers and asked them to select the proceptive face. We tested images that simulated what would be seen by common catarrhine trichromatic vision, two additional trichromatic conditions and three dichromatic conditions. Performance under conditions of common catarrhine trichromacy,and trichromacy with narrowly separated LM cone pigments (common in female platyrrhines), was better than for evenly spaced trichromacy or for any of the dichromatic conditions. These results suggest that primate trichromatic colour vision confers excellent ability to detect meaningful variation in primate face colour. This is consistent with the hypothesis that social information detection has acted on either primate signal spectral reflectance or photoreceptor spectral tuning, or both. [ABSTRACT FROM AUTHOR]

Published
2017
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43. Fooled, but not foolish

Author

Allen, William L.

Subjects
Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Author(s): William L. Allen [1] Sir References to National Geographic in your Opinion article 'Fossil Smuggling Unopposed' [1] are false. The article on new dinosaurs from China was not 'naively [...]

Published
2000
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45. Proceedings of the 4th World Conference on Research Integrity

Author

O’Brien, Susan Patricia, Chan, Danny, Leung, Frederick, Ko, Eun Jung, Kwak, Jin Sun, Gwon, TaeHwan, Lee, Ji Min, Lee, Min-Ho, Nolte, Helga, Gommel, Michael, Sponholz, Gerlinde, Krastev, Yordanka, Sandiran, Yamini, Connell, Julia, Solomon, Nicky, Krasovec, Ursa Opara, Sribar, Renata, Martinson, Brian C., Thrush, Carol R., Gunsalus, C. K., Oransky, Ivan, Marcus, Adam, Graf, Chris, Warne, Verity, Wates, Edward, Joshua, Sue, Roig, Miguel, Mumford, Michael, Deschênes, Mylène, Olivier, Catherine, Dupras-Leduc, Raphaëlle, Hammatt, Zoë, Tamot, Raju, Parker, Robin, Ricard, Cynthia, Nguyen-Khoa, Loc, Titus, Sandra, Jensen, Karsten Klint, Godecharle, Simon, Nemery, Ben, Dierickx, Kris, Gjerris, Mickey, Eriksen, Maud Marion Laird, Hoej, Jeppe Berggren, Steneck, Nicholas H., Nebeker, Camille, Kalichman, Michael, Booen, Elizabeth Mejia, Pacheco, Blanca Azucena, Giacinto, Rebeca Espinosa, Castaneda, Sheila, Li, Ding, Chen, Qiong, Zhu, Guoli, Sun, Zhonghe, Abbasi, Badaruudin, Ganguly, Parthasarathi, Ganguly, Barna, Bonn, Noémie Aubert, Bourcier, Daniele, Bordé, Jacques, Leduc, Michèle, Chou, Chien, Pan, Sophia Jui-An, Tiefenauer, Louis Xaver, Barr, Daniel, Taylor, Paul, Horn, Lyn Margaret, Poff, Deborah, Mavrinac, Martina, Brumini, Gordana, Petrovečki, Mladen, Santos, Christiane Coelho, Vasconcelos, Sonia, Lammey, Rachael, Hartgerink, Chris, van Assen, Marcel, Wicherts, Jelte, Hauge, Hanne Silje, Manka, Aaron, Iturrizaga, Raffael, Foeger, Nicole, Lescano, A. Roxana, Lanata, Claudio, Vasquez, Gissella, Mariana, Leguia, Silva, Marita, Kasper, Mathew, Montero, Claudia, Bausch, Daniel, Lescano, Andres G., Blom, Fenneke, Bouter, Lex, Lategan, Laetus O. K., Manaia, Gustavo Fitas, McCormack, Wayne T., Allen, William L., Connelly, Shane, Crites, Joshua, Engler, Jeffrey, Freedman, Victoria, Garvan, Cynthia W., Haidet, Paul, Hockensmith, Joel, McElroy, William, Sander, Erik, Volpe, Rebecca, Verderame, Michael F., Krstic, Snezana, Handy, Louise, Schaller-Demers, Debra, Lerouge, Inge, Cielen, Gerard, Schoofs, Liliane, Marusic, Ana, Squazzoni, Flaminio, Vaux, David, Al-Wazzan, Khalid, Alorainy, Ibrahim, O’Brien, Nolan, Guerin, Suzanne, Dodd, Philip, Wells, Frank, Blewett, Catherine, Litto, Fredric M., De Lecuona, Itziar, Löfstrom, Erika, Maes, Katrien, Bonn, Noémie, Peatfield, Tony, Boehme, Olivier, Caporale, Cinzia, Fanelli, Daniele, Carfora, John, Strauss, Eric, Lynn, William, De Bruyn, Dieter, Nele, Bracke, De Gelder, Katrien, Van der Burght, Stefanie, e Silva, José Roberto Lapa, Vasconcelos, Sonia M. R., Ingierd, Helene, Frankel, Mark, Vasgird, Daniel, Bird, Stephanie, Yarborough, Mark, Garner, Harold, Campo-Engelstein, Lisa, Master, Zubin, Smith, Elise, Resnik, David, Williams-Jones, Bryn, Malicki, Mario, Utrobicic, Ana, Ioannidis, John P. A., ter Riet, Gerben, Walley, Tom, Bouter, Lex Marius, van der Steen, Jenny, Sorenson, Martha, Prosdocimi, Francisco, Masuda, Hatisaburo, Watanabe, Edson, Pinto, José Carlos, Palácios, Marisa, e Silva, José Lapa, Leta, Jacqueline, Vieyra, Adalberto, Pinto, André, Sant’Ana, Mauricio, Shinkai, Rosemary, Yudin, Boris, Vergès, Etienne, Brun-Wauthier, Anne-Sophie, Vial, Géraldine, Vinther, Torkild, Bähr, Volker, Plemmons, Dena, Davies, Rebecca Lynn, Laube, Katrina, Scheopner, Cynthia, Galland, John, Maisonneuve, Hervé, Decullier, Evelyne, Noble, Brian, Gilis, Anja, Gallacher, David J., Lavrijssen, Tom, David, Malwitz, Dasgupta, Malini, Mols, Hans, Savard, Tony, Mah, Eric, Wager, Elizabeth, Kleinert, Sabine, Kiermer, Veronique, Hufton, Andrew, Clyne, Melanie, Almeida, Renan Moritz, Fontes-Pereira, Aldo, Catelani, Fernanda, Rocha, Karina, Iorns, Elizabeth, Gunn, William, Letellier, Lucienne, Malherbe, Cornelia, Kamata, Takehito, Enebakk, Vidar, Penrod, Lynn, Nørgaard, Thomas, Elverdam, Charlotte, Fassin, Yves, Fekken, Cynthia, Adam, Jamal, Anderson, Melissa S., Buttliere, Brett, Groves, Trish, Shanahan, Daniel, Simera, Iveta, Kirtley, Shona, Villanueva, Eleana, Struthers, Caroline, MacCarthy, Angela, Altman, Douglas, Grebenshchikova, Elena, Greene, Bronwyn, Rohr, Ted, Harriman, Stephanie, Varantola, Krista, Opara, Ursa, Rokne, Jon, Setti, Gianluca, MacPherson, Gordon, Hazelkorn, Ellen, Smith, Carthage, McLaughlin, Robert H., Martins, Tatiana Duque, Tanimoto, Tetsuya, Steneck, Nicholas, Kalleberg, Ragnvald, Hussein, Tajammul, Sun, Ping, Tzeng, Ovid, Zimmerman, Susan, Lescano, Roxana, Heitman, Elizabeth, Nieto, Maria Andrea Rocio del Pilar Contre, Fong, Eric, Wilhite, Al, Motta-Roth, Désirée, Tijdink, Joeri, Smulders, Yvo, Steele, Logan, Watts, Logan, Johnson, James, Williams, Lee, Amini, Sufia, Hooft, Lotty, Kilicoglu, Halil, van Seters, Janneke, Eijsackers, Herman, Voragen, Fons, van der Zijpp, Akke, Brom, Frans, Abbasi, Badaruddin, Almasoud, Naif Nasser, Labuschagne, Adri, Severinsen, Johanne, Engh, Espen, Alani, Daham Ismail, Jusoff, H. J. Kamaruzaman, Gordon, Anita, Harton, Helen C., Rocha, Karina de Albuquerque, de Vasconcelos, Sonia Maria Ramos, Matandika, Limbanazo, Prata, Aline Carolina de Oliveira Machado, Neff, Mark William, Costas, Rodrigo, Larivière, Vincent, Filho, Douglas Leonardo Gomes, Guedes, Diego Oliveira, Keller, Niklas, Feufel, Markus, Offenhauser, Nikolas, Kowalczuk, Maria K., Moylan, Elizabeth C., Speanburg, Katie, Lubomirski, Mariusz, Malwitz, David, Gallacher, David, Gillis, Anja, Marques, Maria Betânia de Freitas, Amâncio, Laressa Lima, Fernandes, Raphaela Dias, Patrocínio, Oliveira, Rech, Cláudia Maria Correia Borges, Sousa, Adriana Nascimento, Garcia, Leila Posenato, Patel, Jigisha, Lada, Farida, Di Capua, Giuseppe, Peppoloni, Silvia, DuBois, James M., Chibnall, John, Van der Wall, Jillon, Tait, Raymond, Holen, Jacob, Johannessen, Adele Flakke, Ellefsen, Torunn, Rech, Claudia, Sousa, Adriana, Beranzoli, Laura, and Beirão, Paulo S. L.

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46. From the Editor.

Author

Allen, William L.

Subjects
*MOUNTAINEERING expeditions
Abstract

Offers observations on the 50th anniversary of the attempt by mountain-climbers Edmund Hillary and Tenzing Norgay to reach the summit of Mount Everest. Our own Barry Bishop--a 31-year-old writer, photographer, and geographer--was part of the team. When I joined the staff of the National Geographic Society in 1969, Barry was already a legend here. After recovering from Everest, where he'd lost his toes and nearly lost his life, the cheerful man with the handlebar mustache turned his boundless energy to promoting science, eventually becoming chairman of the Society's Committee for Research and Exploration. Nine years ago Barry was killed in a car accident. But his family's connection with Everest didn't end. Last spring Barry's son, Brent, joined Sir Edmund's son, Peter, and Tenzing's son Jamling on an expedition to the peak as a tribute to their fathers.

Published
2003

47. Interspecific visual signalling in animals and plants: a functional classification.

Author

Caro T and Allen WL

Subjects
Animals, Models, Biological, Species Specificity, Animal Communication, Biological Evolution, Plants
Abstract

Organisms frequently gain advantages when they engage in signalling with individuals of other species. Here, we provide a functionally structured framework of the great variety of interspecific visual signals seen in nature, and then describe the different signalling mechanisms that have evolved in response to each of these functional requirements. We propose that interspecific visual signalling can be divided into six major functional categories: anti-predator, food acquisition, anti-parasite, host acquisition, reproductive and agonistic signalling, with each function enabled by several distinct mechanisms. We support our classification by reviewing the ecological and behavioural drivers of interspecific signalling in animals and plants, principally focusing on comparative studies that address large-scale patterns of diversity. Collating diverse examples of interspecific signalling into an organized set of functional and mechanistic categories places anachronistic behavioural and morphological labels in fresh context, clarifies terminology and redirects research effort towards understanding environmental influences driving interspecific signalling in nature.This article is part of the themed issue 'Animal coloration: production, perception, function and application'., (© 2017 The Author(s).)

Published
2017
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48. The role of life history traits in mammalian invasion success.

Author

Capellini I, Baker J, Allen WL, Street SE, and Venditti C

Subjects
Animals, Ecosystem, Fertility, Phylogeny, Reproduction, Introduced Species, Mammals, Models, Biological
Abstract

Why some organisms become invasive when introduced into novel regions while others fail to even establish is a fundamental question in ecology. Barriers to success are expected to filter species at each stage along the invasion pathway. No study to date, however, has investigated how species traits associate with success from introduction to spread at a large spatial scale in any group. Using the largest data set of mammalian introductions at the global scale and recently developed phylogenetic comparative methods, we show that human-mediated introductions considerably bias which species have the opportunity to become invasive, as highly productive mammals with longer reproductive lifespans are far more likely to be introduced. Subsequently, greater reproductive output and higher introduction effort are associated with success at both the establishment and spread stages. High productivity thus supports population growth and invasion success, with barriers at each invasion stage filtering species with progressively greater fecundity., (©2015 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.)

Published
2015
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