DOCSLIB.ORG

Predator Personality Structures Prey Communities and Trophic Cascades

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Predator Personality Structures Prey Communities and Trophic Cascades Ecology Letters, (2017) 20: 366–374 doi: 10.1111/ele.12735 LETTER Predator personality structures prey communities and trophic cascades Abstract Denon Start* and Benjamin Intraspecific variation is central to our understanding of evolution and population ecology, yet its Gilbert consequences for community ecology are poorly understood. Animal personality – consistent indi- vidual differences in suites of behaviours – may be particularly important for trophic dynamics, Department of Ecology and Evolu- where predator personality can determine activity rates and patterns of attack. We used meso- tionary Biology, University of Tor- cosms with aquatic food webs in which the top predator (dragonfly nymphs) varied in activity onto Toronto, ON, Canada M5S 3B3 and subsequent attack rates on zooplankton, and tested the effects of predator personality. We *Correspondence: E-mail: denon. found support for four hypotheses: (1) active predators disproportionately reduce the abundance [email protected] of prey, (2) active predators select for predator-resistant prey species, (3) active predators strengthen trophic cascades (increase phytoplankton abundance) and (4) active predators are more likely to cannibalise one another, weakening all other trends when at high densities. These results suggest that intraspecific variation in predator personality is an important determinant of prey abundance, community composition and trophic cascades. Keywords Copepod, Daphnia, Epitheca canis, food web, intraspecific variation, predation competition. Ecology Letters (2017) 20: 366–374 Fussmann et al. 2007; Schoener 2011). Fewer studies have INTRODUCTION addressed the ecological effects of intraspecific trait differences Trait variation is central to our understanding of how individ- within communities, especially on higher order interactions uals interact, and how interactions determine community (but see Johnson & Stinchcombe 2007; Crutsinger et al. 2009; structure. Variation among species is particularly well studied Hughes & Stachowicz 2009). Understanding the consequences with respect to trophic interactions (Brooks & Dodson 1965; of differences among individuals on community processes is Schmitz et al. 2000). Differences in traits of predator species necessary for developing models of how and when the pres- are known to alter prey abundance and identity (Schmitz ence of intraspecific variation should alter dynamics (Bolnick et al. 2000), ultimately influencing ecosystem function (Sch- et al. 2011). mitz & Suttle 2001). For example, decades of research has Animal personalities are one type of intraspecific variation shown that predator identity and abundance structure prey comprising groups of behavioural traits that vary consistently communities and often alter trophic cascades (Paine 1966; among individuals of a given species (Sih et al. 2004; Dinge- Schmitz et al. 2000). This research usually assumes that mean manse et al. 2010). Animal personalities typically have genetic trait values adequately represent species interactions and their underpinnings and are heritable (Dochtermann et al. 2015), effects on community structure. However, using mean trait creating the potential for standing trait variation. For exam- values or simply species identity, ignores considerable ple, activity of larval odonates is heritable (Brodin & Johans- intraspecific trait variation (Benesh & Kalbe 2016), overlook- son 2004), consistent across ontogeny (Brodin 2009) and can ing a potentially important determinant of community struc- in turn alter predator activity and feeding rate (Araujo et al. ture (Bolnick et al. 2011). 2011). Crucially, different personalities can be maintained Intraspecific trait variation in a predator species can alter both within or among populations, with differing conse- community structure and ultimately ecosystem processes. quences for community dynamics (Sih et al. 2012). In short, Intraspecific differences among populations have been shown selection and gene flow can create populations composed of to have large consequences on trophic dynamics (e.g. Morin individuals with disparate personalities (Sih et al. 2012; Wolf 1983; Post et al. 2008). For example, Post et al. (2008) & Weissing 2012), and we expect these differences to have showed that trait variation among populations of a fish important implications for species interactions. predator created differences in plankton communities, algal Although intraspecific differences in animal personalities concentration and ecosystem processes. Within populations, have clear implications for species interactions, their effects on intraspecific variation underpins evolution that can alter higher order interactions remain poorly understood (Toscano predator–prey dynamics (Cortez 2016), and even in the & Griffen 2014; Belgrad & Griffen 2016). When differences in absence of evolution, nonlinear averaging can cause ecological predator personality alter the rate at which they consume dynamics to differ systematically when intraspecific variation prey, they may influence the density, behaviour or identity of is present (Bolnick et al. 2011). The sources and consequences prey species (Royaute & Pruitt 2015), which should in turn of intraspecific variation are best understood from evolution- have cascading effects on basal resources (Paine 1966; Schmitz ary and eco-evolutionary perspectives (Thompson 1988; et al. 2000). Because predators with active personalities can © 2017 John Wiley & Sons Ltd/CNRS Letter Animal personality in food webs 367 consume larger numbers of prey (Sih et al. 2012; Royaute& zooplankton communities and algal abundance, while simulta- Pruitt 2015), these individuals should produce larger trophic neously measuring cannibalism rates. Our study addressed the cascades. We expect these effects of personality to be particu- above ideas, specifically testing if (1) active predators dispro- larly important when communities are strongly structured by portionately reduce prey abundances, (2) predator-resistant predation (Schmitz et al. 2000), and when examining zooplankton species have a higher relative abundance when intraspecific variation in abundant species that interact active predators are present, (3) the combined effects of strongly (Bolnick et al. 2011). reduced prey abundance and changes in zooplankton commu- Predator personality can also change the type of prey nity composition strengthen trophic cascades (increase algal encountered and consumed, directly altering prey community abundance) when active predators are present and (4) canni- composition, and through this change, trophic cascades (Pea- balism weakens the above hypotheses when multiple active cor et al. 2011). In many communities prey fall along a preda- predators are present. We show that natural variation in tion competition continuum, where the most competitive predator activity levels is sufficient to alter prey density and species are efficient foragers that persist with low resources composition and, through these changes, alter trophic cas- (Tilman 1980; Mittelbach 1981) and predation resistance spe- cades. cies are well-defended but inefficient foragers (Werner & Hall 1988; Chase et al. 2002). The greater consumptive effect of active predators should reduce prey abundance, but can also METHODS select for well-defended prey species (Skelly 1995; Post et al. Study system and collection 2008). In other words, predator personality has the potential to selectively alter the prey community, which may alter the We tested the above questions using a dragonfly predator, strength of trophic cascades and allow poorly competing spe- Epitheca canis (hereafter Epitheca), and a simple aquatic food cies to persist. chain. Epitheca larvae are common in fishless ponds through- While active predators should have disproportionately large out northeastern North America and are often the most abun- effects on prey communities and trophic cascades, these pat- dant dragonfly (Anholt et al. 1991). Many odonates are terns may be weakened or reversed by predator–predator cannibalistic (Van Buskirk 1989) and have heritable personal- interactions such as cannibalism (Rudolf 2007). Cannibalism ity traits that are consistent across ontogeny (Brodin & increases with activity rate for at least two reasons. First, Johansson 2004; Brodin 2009). We used two zooplankton spe- active predators encounter prey and each other at a higher cies, a cyclopoid copepod (hereafter copepod) and Daphnia rate (Dell et al. 2011), increasing the opportunity for canni- catawba Coker (hereafter Daphnia), as prey. Both species are balism. Second, the increased metabolic demand of active abundant in ponds in southern Ontario, co-occur with predators (Brit-Friesen et al. 1989; Werner & Anholt 1993) Epitheca, and have largely overlapping ranges. Total zoo- can increase the need for cannibalism. High rates of cannibal- plankton abundance, composed mainly of these species, aver- ism can reduce the abundance of predators, consequently aged 90 individuals per litre when we collected zooplankton increasing the abundance of prey, weakening trophic cascades for our experiments (Start, unpublished data). Unicellular (Rudolf 2007). In addition, if predators are satiated by canni- algae represented the basal resource of the system. Using a balism, they will consume fewer prey, reducing the strength of simplified system allows us to feasibly investigate multi-gen- the trophic cascade on a per predator basis (Rudolf 2007). erational population and community dynamics. Thus, an active predator personality
Load more

Recommended publications
  • A Five-Year Research Program Is Proposed to Expand the Theory of Community Assembly from Its Current Base of Correlative Inferen
    PROJECT SUMMARY A five-year research program is proposed to expand the theory of community assembly from its current base of correlative inferences to one grounded in process-based conclusions derived from controlled field and laboratory experiments. Northern pitcher plants, Sarracenia purpurea, and their community of inquiline arthropods and rotifers, will be used as the model system for the proposed experiments. There are three goals to the proposed research. (1) Inquiline assemblages that colonize pitcher plants will be developed as a model system for understanding community assembly and persistence. (2) Field and laboratory experiments will be used to elucidate causes of inquiline community colonization, assembly, and persistence, and the consequences of inquiline community dynamics for plant leaf allocation patterns, growth, and reproduction, as well as within-plant nutrient cycling. Reciprocal interactions of plant dynamics on inquiline community structure will also be investigated experimentally. (3) Matrix models will be developed to describe reciprocal interactions between inquiline community assembly and persistence, and inquilines’ living host habitats. As an integrated whole, the proposed experiments and models will provide a complete picture of linkages between pitcher-plant inquiline communities and their host plants, at individual leaf and whole-plant scales. This focus on measures of plant performance will fill an apparent lacuna in prior studies of pitcher plant microecosystems, which, with few exceptions, have focused almost exclusively on inquiline population dynamics and interspecific interactions. Plant demography of S. purpurea will be described and modeled for the first time. Complementary, multi-year field and greenhouse experiments will reveal effects of soil and pitcher nutrient composition on leaf allocation, plant growth, and reproduction.
    [Show full text]
  • Chemical Deception Among Ant Social Parasites
    Current Zoology 60 (1): 62–75, 2014 Chemical deception among ant social parasites Rhian M. GUILLEM1, Falko DRIJFHOUT2, Stephen J. MARTIN3* 1 Department of Animal and Plant Sciences, University of Sheffield, S10 2TN, UK 2 Chemical Ecology Group, School of Physical and Geographical Sciences, Lennard-Jones Laboratory, Keele University, ST5 5BG, UK 3 School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, UK Abstract Deception is widespread throughout the animal kingdom and various deceptive strategies are exemplified by social parasites. These are species of ants, bees and wasps that have evolved to invade, survive and reproduce within a host colony of another social species. This is achieved principally by chemical deception that tricks the host workers into treating the invading parasite as their own kin. Achieving levels of acceptance into typically hostile host colonies requires an amazing level of decep- tion as social insects have evolved complex species- and colony-specific recognition systems. This allows the detection of for- eigners, both hetero- and con-specific. Therefore, social parasitic ants not only have to overcome the unique species recognition profiles that each ant species produces, but also the subtle variations in theses profiles which generate the colony-specific profiles. We present data on the level of chemical similarity between social parasites and their hosts in four different systems and then discuss these data in the wider context with previous studies, especially in respect to using multivariate statistical methods when looking for differences in these systems [Current Zoology 60 (1): 6275, 2014]. Keywords Mimicry, Social parasites, Cuticular hydrocarbons, Multivariate statistics Deception by mimicking the pattern of another spe- 1968).
    [Show full text]
  • The Adaptive Significance of Inquiline Parasite Workers
    Received 5December 2002 Accepted 29January 2003 Publishedonline 30April 2003 Theadaptive significance of inquilineparasite workers Seirian Sumner * ,David R.Nash and Jacobus J.Boomsma Departmentof Population Ecology, Zoological Institute, University ofCopenhagen, Universitetsparken 15, DK-2100Copenhagen, Denmark Social parasites exploit thesocially managed resourcesof their host’s society.Inquiline social parasites are dependenton their hostthroughout their life cycle,and so many ofthe traits inherited from their free-living ancestorare removedby natural selection.One trait that is commonly lostis theworker caste, thefunctions of which are adequately fulfilled by hostworkers. The fewinquiline parasites that have retaineda worker casteare thought tobe at atransitional stage in theevolution of social parasitism, and their worker castesare consideredvestigial andnon-adaptive. However, this idea has notbeen tested. Furthermore, whetherinquiline workershave anadaptive role outsidethe usual worker repertoire of foraging, broodcare andcolony maintenance has notbeen examined. In this paper, wepresentdata that suggestthat workersof the inquiline ant Acromyrmexinsinuator play avital role in ensuringthe parasite’ s fitness.We show that thepresence of these parasite workershas apositive effecton the production of parasite sexualsand a negative effecton the production of host sexuals. This suggeststhat inquiline workersplay avital role in suppressinghost queen reproduction, thus promoting therearing ofparasite sexuals.To ourknowledge, these are thefirst
    [Show full text]
  • Download PDF File
    Myrmecological News 20 7-14 Vienna, September 2014 Imperfect chemical mimicry explains the imperfect social integration of the inquiline ant Ectatomma parasiticum (Hymenoptera: Formicidae: Ectatomminae) Fabrice SAVARIT & Renée FÉNÉRON Abstract Inquilinism is an extreme form of social parasitism where the parasite permanently depends on its host. This parasitism is widespread among Formicinae and Myrmicinae ants but rare in other subfamilies, like Ectatomminae where Ectatomma parasiticum FEITOSA & FRESNEAU, 2008 is the sole inquiline described so far. This species is genetically and morpholo- gically very similar to its host, E. tuberculatum (OLIVIER, 1792), and uses its worker force to produce exclusively sexuals. During their life cycle, E. parasiticum queens enter into established host colonies and cohabit with the resident queens over an extended period of time. However, previous experiments in the laboratory have shown that some parasites are attacked by host workers, suggesting that their social integration into host colonies is incomplete or unstable. We thus investigate how the chemical cues of the parasites relate to the host's recognition system. For this, we compare the cuticu- lar hydrocarbon profiles of parasites, host queens and host workers using solid-phase microextraction. Although over- lapping, the chemical profiles of both species are distinct. Parasites have no specific compounds but a reduced total amount of cuticular hydrocarbons compared with hosts. We suggest that E. parasiticum uses an imperfect chemical mimicry stra- tegy as it is well-discriminated by its host species. Key words: Chemical strategy, cuticular hydrocarbons, inquiline ants, Ectatomma parasiticum, Ectatomma tuberculatum. Myrmecol. News 20: 7-14 (online 17 February 2014) ISSN 1994-4136 (print), ISSN 1997-3500 (online) Received 14 June 2013; revision received 12 November 2013; accepted 12 November 2013 Subject Editor: Falko P.
    [Show full text]
  • Exotic Ants (Hymenoptera, Formicidae) of Ohio
    JHR 51: 203–226 (2016) Exotic ants (Hymenoptera, Formicidae) of Ohio 203 doi: 10.3897/jhr.51.9135 RESEARCH ARTICLE http://jhr.pensoft.net Exotic ants (Hymenoptera, Formicidae) of Ohio Kaloyan Ivanov1 1 Department of Recent Invertebrates, Virginia Museum of Natural History, 21 Starling Ave., Martinsville, VA 24112, USA Corresponding author: Kaloyan Ivanov ([email protected]) Academic editor: Jack Neff | Received 9 May 2016 | Accepted 30 June 2016 | Published 29 August 2016 http://zoobank.org/DB4AA574-7B14-4544-A501-B9A8FA1F0C93 Citation: Ivanov K (2016) Exotic ants (Hymenoptera, Formicidae) of Ohio. Journal of Hymenoptera Research 51: 203–226. doi: 10.3897/jhr.51.9135 Abstract The worldwide transfer of plants and animals outside their native ranges is an ever increasing problem for global biodiversity. Ants are no exception and many species have been transported to new locations often with profound negative impacts on local biota. The current study is based on data gathered since the publication of the “Ants of Ohio” in 2005. Here I expand on our knowledge of Ohio’s myrmecofauna by contributing new records, new distributional information and natural history notes. The list presented here contains 10 species with origins in a variety of geographic regions, including South America, Eu- rope, Asia, and Indo-Australia. Two distinct groups of exotics, somewhat dissimilar in their geographic origin, occur in Ohio: a) 3 species of temperate Eurasian origin that have established reproducing outdoor populations; and b) 7 tropical tramp species currently confined to man-made structures. OnlyNylanderia flavipes (Smith, 1874) is currently seen to be of concern although its effects on local ant communities ap- pear to be restricted largely to already disturbed habitats.
    [Show full text]
  • Using Network Theory to Understand and Predict Biological Invasions
    Trends in Ecology & Evolution Review Using Network Theory to Understand and Predict Biological Invasions Carol M. Frost,1,2,* Warwick J. Allen,3 Franck Courchamp,4 Jonathan M. Jeschke,5,6,7 Wolf-Christian Saul,5,6,7,8 and David A. Wardle1,9 Understanding and predicting biological invasions is challenging because of the complexity of many interacting players. A holistic approach is needed with the potential to simultaneously consider all relevant effects and effectors. Using net- works to describe the relevant anthropogenic and ecological factors, from community-level to global scales, promises advances in understanding aspects of invasion from propagule pressure, through establishment, spread, and eco- logical impact of invaders. These insights could lead to development of new tools for prevention and management of invasions that are based on species’ network characteristics and use of networks to predict the ecological effects of invaders. Here, we review the findings from network ecology that show the most promise for invasion biology and identify pressing needs for future 1Department of Forest Ecology and research. Management, Swedish University of Agricultural Sciences, Skogsmarksgränd, SE901 83 Umeå, Scaling up to a Network Approach in Invasion Biology Sweden 2Current address: Department of Understanding and predicting biological invasions and their impacts is a huge challenge in ecol- Renewable Resources, University of ogy that will become more important as the homogenization of Earth’s biota increases [1]. Inva- Alberta, 230D Earth Sciences Building, sion biology’s ability to predict invasions and their impacts has been limited by the lack of Edmonton, AB, Canada T6G 2E3 3The Bio-Protection Research Centre, theoretical frameworks that can incorporate and quantify the formidable ecological complexity Lincoln University, PO Box 84, Lincoln of direct and indirect species interactions over multiple trophic levels [2].
    [Show full text]
  • Evolution of Miniaturisation in Inquiline Parasitic Ants: Timing of Male Elimination in Plagiolepis Pygmaea, the Host of Plagiolepis Xene
    Insect. Soc. 51 (2004) 395–399 0020-1812/04/040395-05 Insectes Sociaux DOI 10.1007/s00040-004-0758-9 © Birkhäuser Verlag, Basel, 2004 Research article Evolution of miniaturisation in inquiline parasitic ants: Timing of male elimination in Plagiolepis pygmaea, the host of Plagiolepis xene S. Aron 1, L. Passera 2 and L. Keller 3 1 Service d’Eco-Ethologie Evolutive, CP 160/12, Université Libre de Bruxelles, 50 av. F.D. Roosevelt, 1050 Brussels, Belgium, e-mail: [email protected] 2 Centre de Recherches sur la Cognition Animale, Université Toulouse III, France, e-mail: [email protected] 3 Institut d’Ecologie, Université de Lausanne, Switzerland, e-mail: [email protected] Received 9 February 2004; revised 20 April 2004; accepted 22 April 2004. Summary. Inquiline ant species are workerless social para- Introduction sites whose queens rely completely on the host worker force to raise their brood. A remarkable feature of inquiline ants is Social parasitism, whereby individuals of a species exploit the small size of sexuals, which are of the same size as or parental care from another species, has evolved repeatedly smaller than host workers. It has been suggested that minia- in eusocial Hymenoptera and has been reported in over 250 turisation evolved by parasites to prevent host workers from species of ants, bees and wasps (Wilson, 1971; Wcislo, 1987; discriminating between their own worker brood and the in- Hölldobler and Wilson, 1990). In its most extreme form, per- quiline sexuals, so that male and female inquilines can devel- manent inquilinism, social parasitism has been associated op under conditions where the host species does not produce with the loss of the worker caste.
    [Show full text]
  • The Crab Spider–Pitcher Plant Relationship Is a Nutritional Mutualism That Is Dependent on Prey- Resource Quality
    Received: 5 July 2018 | Accepted: 28 September 2018 DOI: 10.1111/1365-2656.12915 RESEARCH ARTICLE The crab spider–pitcher plant relationship is a nutritional mutualism that is dependent on prey- resource quality Weng Ngai Lam | Hugh T. W. Tan Department of Biological Sciences, National University of Singapore, Singapore, Abstract Singapore 1. Nutritional mutualisms are one of the three major categories of mutualisms and Correspondence involve the provision of limiting nutrients (resources) to one species by another. It Weng Ngai Lam was recently shown in laboratory experiments that two species of pitcher-dwell- Email: [email protected] ing crab spiders (Thomisidae), Thomisus nepenthiphilus and Misumenops nepen- Handling Editor: Audrey Dussutour thicola, increased capture rates of flesh flies (Sarcophagidae) for their host, Nepenthes gracilis. The spiders ambushed pitcher-visiting flesh flies and dropped their carcasses into pitchers after consuming them. The consumption of shared prey-resources by crab spiders and pitcher plants presents the possibility of para- sitism between them. However, ecologically generalizable mechanisms that pre- dict the context-dependent outcomes of such mutualisms are not known. 2. The effectiveness framework (mutualism effectiveness = quality × quantity) is useful for examining the total effect of mutualisms, but its quality component can be difficult to define. We identify the crab spider–pitcher plant interaction as a type of resource conversion mutualism and propose that the quality component in such interactions is the amount of the underlying resource contained in each unit of resource processed. We then used the crab spider–pitcher plant interaction to test the hypothesis that resource conversion mutualisms are more beneficial to the nutrient recipient when operating through high-quality resources (i.e., large prey, in this interaction).
    [Show full text]
  • Latin Derivatives Dictionary
    Dedication: 3/15/05 I dedicate this collection to my friends Orville and Evelyn Brynelson and my parents George and Marion Greenwald. I especially thank James Steckel, Barbara Zbikowski, Gustavo Betancourt, and Joshua Ellis, colleagues and computer experts extraordinaire, for their invaluable assistance. Kathy Hart, MUHS librarian, was most helpful in suggesting sources. I further thank Gaylan DuBose, Ed Long, Hugh Himwich, Susan Schearer, Gardy Warren, and Kaye Warren for their encouragement and advice. My former students and now Classics professors Daniel Curley and Anthony Hollingsworth also deserve mention for their advice, assistance, and friendship. My student Michael Kocorowski encouraged and provoked me into beginning this dictionary. Certamen players Michael Fleisch, James Ruel, Jeff Tudor, and Ryan Thom were inspirations. Sue Smith provided advice. James Radtke, James Beaudoin, Richard Hallberg, Sylvester Kreilein, and James Wilkinson assisted with words from modern foreign languages. Without the advice of these and many others this dictionary could not have been compiled. Lastly I thank all my colleagues and students at Marquette University High School who have made my teaching career a joy. Basic sources: American College Dictionary (ACD) American Heritage Dictionary of the English Language (AHD) Oxford Dictionary of English Etymology (ODEE) Oxford English Dictionary (OCD) Webster’s International Dictionary (eds. 2, 3) (W2, W3) Liddell and Scott (LS) Lewis and Short (LS) Oxford Latin Dictionary (OLD) Schaffer: Greek Derivative Dictionary, Latin Derivative Dictionary In addition many other sources were consulted; numerous etymology texts and readers were helpful. Zeno’s Word Frequency guide assisted in determining the relative importance of words. However, all judgments (and errors) are finally mine.
    [Show full text]
  • Title Evolutionary History of a Global Invasive Ant, Paratrechina
    Evolutionary history of a global invasive ant, Paratrechina Title longicornis( Dissertation_全文 ) Author(s) Tseng, Shu-Ping Citation 京都大学 Issue Date 2020-03-23 URL https://doi.org/10.14989/doctor.k22480 許諾条件により本文は2021-02-01に公開; 1. Tseng, Shu- Ping, et al. "Genetic diversity and Wolbachia infection patterns in a globally distributed invasive ant." Frontiers in genetics 10 (2019): 838. doi: 10.3389/fgene.2019.00838 (The final publication is available at Frontier in genetics via https://www.frontiersin.org/article/10.3389/fgene.2019.00838/f ull) 2. Tseng, Shu-Ping, et al. "Isolation and characterization of novel microsatellite markers for a globally distributed invasive Right ant Paratrechina longicornis (Hymenoptera: Formicidae)." European Journal of Entomology 116 (2019): 253-257. doi: 10.14411/eje.2019.029 (The final publication is available at European Journal of Entomology via https://www.eje.cz/artkey/eje-201901- 0029_isolation_and_characterization_of_novel_microsatellite_ markers_for_a_globally_distributed_invasive_ant_paratrec.php ) Type Thesis or Dissertation Textversion ETD Kyoto University Evolutionary history of a global invasive ant, Paratrechina longicornis Shu-Ping Tseng 2020 Contents Chapter 1 General introduction ...................................................................................... 1 1.1 Invasion history of Paratrechina longicornis is largely unknown ............... 1 1.2 Wolbachia infection in Paratrechina longicornis ......................................... 2 1.3 Unique reproduction mode in Paratrechina
    [Show full text]
  • An Access-Dictionary of Internationalist High Tech Latinate English
    An Access-Dictionary of Internationalist High Tech Latinate English Excerpted from Word Power, Public Speaking Confidence, and Dictionary-Based Learning, Copyright © 2007 by Robert Oliphant, columnist, Education News Author of The Latin-Old English Glossary in British Museum MS 3376 (Mouton, 1966) and A Piano for Mrs. Cimino (Prentice Hall, 1980) INTRODUCTION Strictly speaking, this is simply a list of technical terms: 30,680 of them presented in an alphabetical sequence of 52 professional subject fields ranging from Aeronautics to Zoology. Practically considered, though, every item on the list can be quickly accessed in the Random House Webster’s Unabridged Dictionary (RHU), updated second edition of 2007, or in its CD – ROM WordGenius® version. So what’s here is actually an in-depth learning tool for mastering the basic vocabularies of what today can fairly be called American-Pronunciation Internationalist High Tech Latinate English. Dictionary authority. This list, by virtue of its dictionary link, has far more authority than a conventional professional-subject glossary, even the one offered online by the University of Maryland Medical Center. American dictionaries, after all, have always assigned their technical terms to professional experts in specific fields, identified those experts in print, and in effect held them responsible for the accuracy and comprehensiveness of each entry. Even more important, the entries themselves offer learners a complete sketch of each target word (headword). Memorization. For professionals, memorization is a basic career requirement. Any physician will tell you how much of it is called for in medical school and how hard it is, thanks to thousands of strange, exotic shapes like <myocardium> that have to be taken apart in the mind and reassembled like pieces of an unpronounceable jigsaw puzzle.
    [Show full text]
  • The Metacommunity Concept: a Framework for Multi-Scale Community Ecology
    Ecology Letters, (2004) 7: 601–613 doi: 10.1111/j.1461-0248.2004.00608.x REVIEW The metacommunity concept: a framework for multi-scale community ecology Abstract M. A. Leibold,1* M. Holyoak,2 The metacommunity concept is an important way to think about linkages between N. Mouquet,3,4 P. Amarasekare,5 different spatial scales in ecology. Here we review current understanding about this J. M. Chase,6 M. F. Hoopes,7 concept. We first investigate issues related to its definition as a set of local communities 8 9 10 R. D. Holt, J. B. Shurin, R. Law, that are linked by dispersal of multiple potentially interacting species. We then identify D. Tilman,11 M. Loreau12 and 13 four paradigms for metacommunities: the patch-dynamic view, the species-sorting view, A. Gonzalez the mass effects view and the neutral view, that each emphasizes different processes of potential importance in metacommunities. These have somewhat distinct intellectual histories and we discuss elements related to their potential future synthesis. We then use this framework to discuss why the concept is useful in modifying existing ecological thinking and illustrate this with a number of both theoretical and empirical examples. As ecologists strive to understand increasingly complex mechanisms and strive to work across multiple scales of spatio-temporal organization, concepts like the metacommunity can provide important insights that frequently contrast with those that would be obtained with more conventional approaches based on local communities alone. Keywords Mass effects, metacommunity, neutral model, patch dynamics, species sorting. Ecology Letters (2004) 7: 601–613 2002). Remarkably, however, much of formal community INTRODUCTION theory is focused on a single scale, assuming that local Community ecology as a field is concerned with explaining communities are closed and isolated.
    [Show full text]