{"title":"Does a Simple Cope's Rule Mechanism Overlook Predators?","authors":"V. Penteriani, R. Kenward","doi":"10.1155/2007/92684","DOIUrl":"https://doi.org/10.1155/2007/92684","url":null,"abstract":"The Cope’s rule predicts a tendency for species to evolve towards an increase in size. Recently, it has been suggested that such a tendency is due to the fact that large body sizes provide a general increase in individual fitness. Here we highlight evidence that predator species do not always fit the large-size = high-fitness mechanism for Cope’s rule. Given the specific requirements of predators and the complexity of prey-predator relationships, any analysis that does not take into account all animal groups may overlook a significant portion of evolutive trends. Generalisations may not be possible regardless of taxa.","PeriodicalId":123249,"journal":{"name":"Research Letters in Ecology","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114507457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Mucientes, N. Queiroz, S. Pierce, I. Sazima, J. Brunnschweiler
{"title":"Is Host Ectoparasite Load Related to Echeneid Fish Presence","authors":"G. Mucientes, N. Queiroz, S. Pierce, I. Sazima, J. Brunnschweiler","doi":"10.1155/2008/107576","DOIUrl":"https://doi.org/10.1155/2008/107576","url":null,"abstract":"This study used field data of echeneid and ectoparasite associations with free-swimming whale sharks (Rhincodon typus) and captured mako sharks (Isurus oxyrinchus) to test whether (1) echeneid presence was positively correlated with ectoparasite presence; and (2) the number of ectoparasites was negatively correlated with the number of echeneid fish. Data from whale and mako sharks do not support the first hypothesis whereas data from mako sharks yields support for the second hypothesis. The results indicate that echeneids do regulate the number of ectoparasites on at least some host species, but these benefits may be contingent on the echeneid species.","PeriodicalId":123249,"journal":{"name":"Research Letters in Ecology","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123407917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shane J. Prochnow, J. White, Thadd Scott, Chris T. Filstrup
{"title":"Small Reservoir Impact on Simulated Watershed-Scale Nutrient Yield","authors":"Shane J. Prochnow, J. White, Thadd Scott, Chris T. Filstrup","doi":"10.1155/2007/12571","DOIUrl":"https://doi.org/10.1155/2007/12571","url":null,"abstract":"The soil and water assessment tool (SWAT) is used to assess the influence of small upland reservoirs (PL566) on watershed nutrient yield. SWAT simulates the impact of collectively increasing and decreasing PL566 magnitudes (size parameters) on the watershed. Totally removing PL566 reservoirs results in a 100% increase in total phosphorus and an 82% increase in total nitrogen, while a total maximum daily load (TMDL) calling for a 50% reduction in total phosphorus can be achieved with a 500% increase in the magnitude of PL566s in the watershed. PL566 reservoirs capture agriculture pollution in surface flow, providing long-term storage of these constituents when they settle to the reservoir beds. A potential strategy to reduce future downstream nutrient loading is to enhance or construct new PL566 reservoirs in the upper basin to better capture agricultural runoff.","PeriodicalId":123249,"journal":{"name":"Research Letters in Ecology","volume":"67 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128356368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Species Diversity Enhances Predator Growth Rates","authors":"M. H. Olson, R. Jacobs, E. O'Donnell","doi":"10.1155/2007/94587","DOIUrl":"https://doi.org/10.1155/2007/94587","url":null,"abstract":"Predators can be important top-down regulators of community structure and are known to have both positive and negative effects on species diversity. However, little is known about the reciprocal effects of species diversity on predators. Across a set of 80 lakes in Connecticut, USA, we found a strong positive correlation between prey species diversity (using the Shannon-Weiner Diversity Index) and growth rates of largemouth bass (Micropterus salmoides). This correlation was strongest for small predators and decreased with body size. Although the underlying mechanisms are not known, the correlation is not driven by total fish abundance, predator abundance, or productivity.","PeriodicalId":123249,"journal":{"name":"Research Letters in Ecology","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133488955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Barrett, Christina M. Romagosa, Matthew I. Williams
{"title":"Long-Term Bird Assemblage Trends in Areas of High and Low Human Population Density","authors":"K. Barrett, Christina M. Romagosa, Matthew I. Williams","doi":"10.1155/2008/202606","DOIUrl":"https://doi.org/10.1155/2008/202606","url":null,"abstract":"Urban areas are expanding globally, and the impact of high human population density (HHPD) on bird species richness remains unresolved. Studies primarily focus on species richness along an urban-to-rural gradient; however, some studies have analyzed larger-scale patterns and found results that contrast with those obtained at smaller scales. To move the discussion beyond static species richness patterns, we analyzed the effect of HHPD on bird assemblage dynamics (year-to-year extinction probability, turnover, changes in species richness) across the United States over a 25-year period. We found that bird assemblages in both high and low human population density areas changed significantly over the period of record. Specifically, bird assemblages increased in species richness on average. Assemblage change in areas of HHPD was not significantly different from assemblage change in areas with LHPD. These results suggest that human population density alone does not alter the persistence of avian assemblage patterns.","PeriodicalId":123249,"journal":{"name":"Research Letters in Ecology","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116904451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Host Specificity in the Parasitic Plant Cytinus hypocistis","authors":"Chris J. Thorogood, S. Hiscock","doi":"10.1155/2007/84234","DOIUrl":"https://doi.org/10.1155/2007/84234","url":null,"abstract":"Host specificity in the parasitic plant Cytinus hypocistis was quantified at four sites in the Algarve region of Portugal from 2002 to 2007. The parasite was found to be locally host specific, and only two hosts were consistently infected: Halimium halimifolium and Cistus monspeliensis. C. hypocistis did not infect hosts in proportion to their abundance; at three sites, 100% of parasites occurred on H. halimifolium which represented just 42.4%, 3% and 19.7% of potential hosts available, respectively. At the remaining site, where H. halimifolium was absent, 100% of parasites occurred on C. monspeliensis which represented 81.1% of potential hosts available. Other species of potential host were consistently uninfected irrespective of their abundance. Ecological niche divergence of host plants H. halimifolium and C. monspeliensis may isolate host-specific races of C. hypocistis, thereby potentially driving allopatric divergence in this parasitic plant.","PeriodicalId":123249,"journal":{"name":"Research Letters in Ecology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129077779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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