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183
2012 Landscape genetics of a specialized grasshopper inhabiting highly fragmented habitats: a role for spatial scale
- Divers. Distrib
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Variation in rhodolith morphology and biogenic potential of newly-discovered rhodolith beds
- in Newfoundland and Labrador (Canada): Botanica Marina
, 2012
"... Abstract For the fi rst time the subarctic northwestern Atlantic, we examined variation in rhodolith ( Lithothamnion glaciale ) morphology and biogenic potential in two large ( > 500 m 2 ) rhodolith beds we discovered recently between the depths of 5 -25 m off St. Philip ' s and Holyrood, N ..."
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Abstract For the fi rst time the subarctic northwestern Atlantic, we examined variation in rhodolith ( Lithothamnion glaciale ) morphology and biogenic potential in two large ( > 500 m 2 ) rhodolith beds we discovered recently between the depths of 5 -25 m off St. Philip ' s and Holyrood, Newfoundland and Labrador. Rhodoliths at St. Philip ' s were > 50 % larger and contained 7 % more internal space in deep (15 -17 m) than shallow (8 -10 m) water, whereas shallow rhodoliths were > 180 % larger at Holyrood than at St. Philip ' s. ). There was a strong positive relationship (R2>0.93) between rhodolith volume and dry weight in both beds. Invertebrates associated with shallow rhodoliths belonging to the taxonomic groups Asteroidea, Echinoidea, Ophiuroidea, Bivalvia, Gastropoda, Polyplacophora, Crustacea, and Annelida were present at both sites, although they varied in terms of size, density, and biomass. Brittle stars ( Ophiopholis aculeata ) and chitons ( Tonicella marmorea ) accounted for at least 82 % (up to 2026.7 individuals m -2 ) of total numbers of invertebrates in each bed. Larger rhodoliths appeared to facilitate reproduction and feeding in dominant fi sh and invertebrate species. Differences in hydrodynamic conditions within and between beds may have contributed to these patterns.
New primary resource increases predation on a pest in a banana
"... agroecosystem ..."
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PERFORMANCES OF DIFFERENT ESTIMATION METHODS FOR GENERALIZED LINEAR MIXED MODELS PERFORMANCES OF DIFFERENT ESTIMATION METHODS FOR GENERALIZED LINEAR MIXED MODELS BY
"... Generalized linear mixed models (GLMMs) have become extremely popular in recent years. The main computational problem in parameter estimation for GLMMs is that, in contrast to linear mixed models, closed analytical expressions for the likelihood are not available. To overcome this problem, several a ..."
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Generalized linear mixed models (GLMMs) have become extremely popular in recent years. The main computational problem in parameter estimation for GLMMs is that, in contrast to linear mixed models, closed analytical expressions for the likelihood are not available. To overcome this problem, several approaches have been proposed in the literature. For this study we have used one quasi-likelihood approach, penalized quasi-likelihood (PQL), and two integral approaches: Laplace and adaptive Gauss-Hermite quadrature (AGHQ) approximation. Our primary objective was to measure the performances of each estimation method. AGHQ approximation is more accurate than Laplace approximation, but slower. So the question is when Laplace approximation is adequate, versus when AGHQ approximation provides a significantly more accurate result. We have run two simulations using PQL, Laplace and AGHQ approximations with different quadrature points for varying random effect standard deviation (θ) and number of replications per cluster. The performances of these three methods were measured base on the root mean square error (RMSE) and bias. Based on the simulated data, we have found that for both smaller values of θ and
in ve
, 2013
"... MS. number: A13-00177 ay b h a phy arro ck. song, but only a weak predictor of attack. We used a two-part playback design to test these predictions, with an initial edge playback from just off the subject’s territory using a song type that the subject matching. Matching the edge playback also was no ..."
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MS. number: A13-00177 ay b h a phy arro ck. song, but only a weak predictor of attack. We used a two-part playback design to test these predictions, with an initial edge playback from just off the subject’s territory using a song type that the subject matching. Matching the edge playback also was not associated with physical measures of aggression ggress Waas anation at disp essive progression of discretely different signals. Here we test a specific model of hierarchical signalling proposed for song sparrows, Melospizamelodia, by Beecher and colleagues (Beecher & Campbell 2005; Searcy & Beecher 2009; Akçay et al. 2013). s (Clutton-Brock & ed for fallow deer, d here it has been ression, with one other (Bartoset al. e blue penguins, c displays given by these birds (Waas 1990,1991b), two vocalizations, growls andhisses, appear to form a hierarchy of threat. When confronted with a model penguin at their burrows, lonemales that give growls aremore likely to attack thanmales that remain silent, andmales that give hisses are more likely to attack than those that growl (Waas 1991a). Thus hisses are a more reliable threat than growls. Themodel of hierarchical aggressive signalling in song sparrows emerged from work by Beecher and colleagues on matching be-haviours. In song type matching, one individual replies to another
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"... i Table of Contents List of tables.........................................................................................................................v List of figures...................................................................................................................... vi Acknow ..."
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i Table of Contents List of tables.........................................................................................................................v List of figures...................................................................................................................... vi Acknowledgements..............................................................................................................1
Reproductive success of Cabralea canjerana (Meliaceae) in Atlantic forest fragments, Brazil Edivani Villaron Franceschinelli1, Roselaini Mendes do Carmo2, Carlos de Melo e Silva Neto1,
"... Abstract: In Brazil, the Atlantic forest remnants have high biological diversity and a high level of endemism, but very little is known about the reproductive success of native species. Cabralea canjerana is a common tree in the Montane Atlantic forest, and its reproduction is highly dependent on po ..."
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Abstract: In Brazil, the Atlantic forest remnants have high biological diversity and a high level of endemism, but very little is known about the reproductive success of native species. Cabralea canjerana is a common tree in the Montane Atlantic forest, and its reproduction is highly dependent on pollinators. In order to contribute with the particular knowledge on this species, we collected data in three fragmented and three continuous forest sites, where the effects of fragmentation on both mutualistic (pollination) and antagonistic (seed predation) interac-tions were analysed. We determined fruit production and weight of 25 trees per site. The number of seeds and the percentage of predated and aborted seeds were also accessed for seven fruits of 10 trees per site. Pollinator visitation frequencies to flowers were recorded in two forest fragments and in two sites of the continuous forest. Our data showed that plants of C. canjerana produced more fruits (z-value=-8.24; p<0.0001) and seeds per fruit (z-value=-6.58; p=0.002) in the continuous than in the fragmented sites. This was likely due to differences in pollination, because the number of pollinator visits was higher in the continuous forest than in the fragments. Seed abortion (z-value=4.08, p<0.001) and predation (z-value=3.72, p=0.0002), on the other hand, were higher in the fragmented than in the continuous sites. Then, mutualistic and antagonistic interactions were affected by
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"... Disruptive viability selection on a black plumage trait associated with dominance ..."
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Disruptive viability selection on a black plumage trait associated with dominance
