The role of sampling effort, taxonomical resolution and abundance weight in multivariate comparison of stream dwelling caddisfly assemblages collected from riffle and pool habitats

2011 ◽  
Vol 11 (2) ◽  
pp. 230-239 ◽  
Author(s):  
Dénes Schmera ◽  
Tibor Erős
Keyword(s):  
Sampling Effort

Ectoparasites of small-mammals: determinants of community structure in South American savannah

Parasitology ◽  
2016 ◽  
Vol 144 (4) ◽  
pp. 475-483 ◽  
Author(s):  
J. SPONCHIADO ◽  
G. L. MELO ◽  
T. F. MARTINS ◽  
F. S. KRAWCZAK ◽  
F. C. JACINAVICIUS ◽  
...  
Keyword(s):  
Body Mass ◽  
Host Species ◽  
Important Variable ◽  
Sampling Effort ◽  
South American ◽  
Central Brazil ◽  
Significant Relationships ◽  
Weak Influence ◽  
Host Body Mass

SUMMARYThis study aimed to assess the contribution of hosts characteristics (rodents and marsupials) in the organization of ectoparasite communities present in woodland patches in western central Brazil. We verified the effect of host species, sex, body mass and vertical strata in addition to the role of seasonality on the ectoparasite composition, richness and abundance. The total sampling effort was 22 032 trap-nights equally distributed in 54 woodland patches. Variance partition and principal coordinate analysis were used to verify the existence of significant relationships between response variables and predictors. As expected, host species was the most important variable in ectoparasite community assembly. The composition, richness and abundance of mites and lice were highly influenced by host species, although higher for mites than for lice. Host body mass had a determining role on the richness and abundance of tick species. Vertical stratification and seasonality had weak influence, while the sex of the host had no influence on the organization of these communities. The results are closely related to the evolutionary characteristics of the species involved, as well as with local environmental characteristics of the study area.

scholarly journals Geostatistics as a tool to improve sampling and statistical analysis in wetlands: a case sudy on dynamics of organic matter distribution in the Pantanal of Mato Grosso, Brazil

2002 ◽  
Vol 62 (4b) ◽  
pp. 861-870 ◽  
Author(s):  
F. NOGUEIRA ◽  
E. G. COUTO ◽  
C. J. BERNARDI
Keyword(s):  
Organic Matter ◽  
Flood Pulse ◽  
Sampling Effort ◽  
Classical Statistic ◽  
Mato Grosso ◽  
Money Economy ◽  
Landscape Units ◽  
A Minor ◽  
Flooded Areas

The Pantanal of Mato Grosso presents distinct landscape units: permanently, occasionally and periodically flooded areas. In the last ones, sampling is especially difficult due to the high heterogeneity occurring inter and intrastratas. This paper presents a comparison of different methodological approaches showing that they can influence decisively the knowledge of distribution organic matter dynamics. In such an area in order to understand the role of the flood pulse in the distribution dynamics of organic matter in a wetland at the Pantanal, we considered that there is spatial dependence between points. This consideration contradicts the classical statistic principle that focuses on the aleatority, and allowed the obtainment of a larger volume of information from a minor sampling effort, which means better performance, with time and money economy.

scholarly journals Resolution of biodiversity and assemblage structure in demersal fisheries surveys: the role of tow duration

2018 ◽  
Vol 75 (5) ◽  
pp. 1672-1681 ◽  
Author(s):  
M Moriarty ◽  
A F Sell ◽  
V M Trenkel ◽  
C P Lynam ◽  
F Burns ◽  
...  
Keyword(s):  
Species Richness ◽  
Body Size ◽  
Significant Loss ◽  
Sampling Effort ◽  
Large Fish ◽  
The North ◽  
Commercial Species ◽  
The North Sea ◽  
Typical Length

Abstract An experiment during a fisheries independent survey in the North Sea was conducted to test whether sampling effort could be reduced without a significant loss in data precision. To examine potential effects of reducing tow duration from the standard 30 min to a proposed 15 min estimates of species encounter rates, species richness, and estimates of abundance, biomass, and body size were analysed. Results show species richness estimates are lower in the short tow category. While biomass and abundance at length and body size are significantly affected by the change in tow duration, estimates of Large Fish Indicator, the Typical length and Mean-max length are not significantly affected by the regime change. The results presented here suggest that a reduction of tow duration did not optimize the resolution of biodiversity, and it may affect other survey objectives, such as, providing estimates of abundance or biomass for assessment of commercial species.

scholarly journals Challenges in assessing the roles of nepotism and reciprocity in cooperation networks

2018 ◽  
Author(s):  
Gerald G. Carter ◽  
Gabriele Schino ◽  
Damien Farine
Keyword(s):  
Social Relationships ◽  
Empirical Data ◽  
Statistical Power ◽  
Japanese Macaques ◽  
Sampling Effort ◽  
Relative Role ◽  
Vampire Bats ◽  
Two Factors ◽  
Resampling Procedure

AbstractNepotism and reciprocity are not mutually exclusive explanations for cooperation, because helping decisions can depend on both kinship cues and past reciprocal help. The importance of these two factors can therefore be difficult to disentangle using observational data. We developed a resampling procedure for inferring the statistical power to detect observational evidence of nepotism and reciprocity. We first applied this procedure to simulated datasets resulting from perfect reciprocity, where the probability and duration of helping events from individual A to B equaled that from B to A. We then assessed how the probability of detecting correlational evidence of reciprocity was influenced by (1) the number of helping observations and (2) varying degrees of simultaneous nepotism. Last, we applied the same analysis to empirical data on food sharing in vampire bats and allogrooming in mandrills and Japanese macaques. We show that at smaller sample sizes, the effect of kinship was easier to detect and the relative role of kinship was overestimated compared to the effect of reciprocal help in both simulated and empirical data, even with data simulating perfect reciprocity and imperfect nepotism. We explain the causes and consequences of this difference in power for detecting the roles of kinship versus reciprocal help. To compare the relative importance of genetic and social relationships, we therefore suggest that researchers measure the relative reliability of both coefficients in the model by plotting these coefficients and their detection probability as a function of sampling effort. We provide R scripts to allow others to do this power analysis with their own datasets.

Role of dactinomycin in the improved survival of children with Wilms' tumor

JAMA ◽  
1966 ◽  
Vol 195 (12) ◽  
pp. 1005-1009 ◽  
Author(s):  
D. J. Fernbach
Keyword(s):  
Wilms Tumor

Role of the allergist in diagnosis and management of patients with uveitis

JAMA ◽  
1966 ◽  
Vol 195 (3) ◽  
pp. 167-172 ◽  
Author(s):  
T. E. Van Metre
Keyword(s):  
Diagnosis And Management

The power of norms to sway fused group members

2018 ◽  
Vol 41 ◽  
Author(s):  
Winnifred R. Louis ◽  
Craig McGarty ◽  
Emma F. Thomas ◽  
Catherine E. Amiot ◽  
Fathali M. Moghaddam
Keyword(s):  
Evolutionary Anthropology ◽  
Normative Systems ◽  
Violent Extremism ◽  
Identity Fusion ◽  
Group Members

AbstractWhitehouse adapts insights from evolutionary anthropology to interpret extreme self-sacrifice through the concept of identity fusion. The model neglects the role of normative systems in shaping behaviors, especially in relation to violent extremism. In peaceful groups, increasing fusion will actually decrease extremism. Groups collectively appraise threats and opportunities, actively debate action options, and rarely choose violence toward self or others.

Sign in / Sign up

Export Citation Format

Share Document