scholarly journals Indicators of body size variability in a highly developed small-scale fishery: Ecological and management implications

2021 ◽  
Vol 121 ◽  
pp. 107141
Author(s):  
Alexandre Alonso-Fernández ◽  
Jaime Otero ◽  
Rafael Bañón
Keyword(s):  
Body Size ◽  
Small Scale ◽  
Management Implications ◽  
Size Variability

scholarly journals The evolution of body size in termites

2021 ◽  
Vol 288 (1963) ◽  
Author(s):  
Nobuaki Mizumoto ◽  
Thomas Bourguignon
Keyword(s):  
Body Size ◽  
Size Reduction ◽  
Head Width ◽  
Termite Species ◽  
Fossil Species ◽  
Modern Species ◽  
Size Evolution ◽  
Phylogenetic Framework ◽  
Size Variability ◽  
Width Measurements

Termites are social cockroaches. Because non-termite cockroaches are larger than basal termite lineages, which themselves include large termite species, it has been proposed that termites experienced a unidirectional body size reduction since they evolved eusociality. However, the validity of this hypothesis remains untested in a phylogenetic framework. Here, we reconstructed termite body size evolution using head width measurements of 1638 modern and fossil termite species. We found that the unidirectional body size reduction model was only supported by analyses excluding fossil species. Analyses including fossil species suggested that body size diversified along with speciation events and estimated that the size of the common ancestor of modern termites was comparable to that of modern species. Our analyses further revealed that body size variability among species, but not body size reduction, is associated with features attributed to advanced termite societies. Our results suggest that miniaturization took place at the origin of termites, while subsequent complexification of termite societies did not lead to further body size reduction.

Reproductive patterns of European pond turtles differ between sites: a small scale scenario

2015 ◽  
Vol 36 (4) ◽  
pp. 339-349
Author(s):  
Marco A.L. Zuffi ◽  
Elena Foschi
Keyword(s):  
Body Size ◽  
Egg Production ◽  
Shell Height ◽  
The Body ◽  
Small Scale ◽  
Central Mediterranean ◽  
Population Structures ◽  
Body Sizes ◽  
Reproductive Females ◽  
Similar Body

From 1996 to 2002, we studied the body size, measures of reproductive strategy (relative clutch mass and delayed reproduction at sexual maturity), and reproductive output (clutch frequency and annual egg production) of female European Pond turtles,Emys orbicularis, at two sites separated by 12 km in central Mediterranean Tuscany (San Rossore and Camp Darby, central northern Italy). Females did not reproduce at the first appearance of external sexual characters, but reproduced at larger sizes, probably as older turtles. Among years, reproductive females were more common than were non-reproductive females, yet both groups had similar body sizes. Body size (carapace length and width, plastron length and width, shell height and body mass) varied between localities and among years. Body size differed between reproductive and non reproductive females in Camp Darby, but not in San Rossore females. Shell volume did not vary among years, nor between localities, nor between reproductive status. Reproductive females had higher body condition indices (BCI) than did non-reproductive females, while BCI did not differ between females laying one clutch and females laying multiple clutches. Clutch size did not vary among years. One clutch per year was much more frequent than multiple clutches, and multiple clutches were more frequent in Camp Darby than in San Rossore females, likely due to differences in population structures between sites.

scholarly journals Small-Scale Drop Size Variability: Impact on Estimation of Cloud Optical Properties

2005 ◽  
Vol 62 (7) ◽  
pp. 2555-2567 ◽  
Author(s):  
Y. Knyazikhin ◽  
R. B. Myneni ◽  
A. Marshak ◽  
W. J. Wiscombe ◽  
M. L. Larsen ◽  
...  
Keyword(s):  
Drop Size ◽  
Water Drop ◽  
Small Scale ◽  
Size Dependent ◽  
Radiative Impact ◽  
Size Variability ◽  
The Mean ◽  
Conventional Models ◽  
Processing Techniques ◽  
The Impact

Abstract Most cloud radiation models and conventional data processing techniques assume that the mean number of drops of a given radius is proportional to volume. The analysis of microphysical data on liquid water drop sizes shows that, for sufficiently small volumes, this proportionality breaks down; the number of cloud drops of a given radius is instead proportional to the volume raised to a drop size–dependent nonunit power. The coefficient of proportionality, a generalized drop concentration, is a function of the drop size. For abundant small drops the power is unity as assumed in the conventional approach. However, for rarer large drops, it falls increasingly below unity. This empirical fact leads to drop clustering, with the larger drops exhibiting a greater degree of clustering. The generalized drop concentration shows the mean number of drops per cluster, while the power characterizes the occurrence frequency of clusters. With a fixed total number of drops in a cloud, a decrease in frequency of clusters is accompanied by a corresponding increase in the generalized concentration. This initiates a competing process missed in the conventional models: an increase in the number of drops per cluster enhances the impact of rarer large drops on cloud radiation while a decrease in the frequency suppresses it. Because of the nonlinear relationship between the number of clustered drops and the volume, these two opposite tendencies do not necessarily compensate each other. The data analysis suggests that clustered drops likely have a stronger radiative impact compared to their unclustered counterpart; ignoring it results in underestimation of the contribution from large drops to cloud horizontal optical path.

scholarly journals A global analysis of cladoceran body size and its variation linking to habitat, distribution and taxonomy

2019 ◽  
Vol 187 (4) ◽  
pp. 1119-1130 ◽  
Author(s):  
Eric Zeus Rizo ◽  
Shaolin Xu ◽  
Quehui Tang ◽  
Rey Donne S Papa ◽  
Henri J Dumont ◽  
...  
Keyword(s):  
Body Size ◽  
Large Scale ◽  
Global Analysis ◽  
Functional Trait ◽  
Categorical Variables ◽  
Extensive Literature ◽  
Frequency Distributions ◽  
Size Frequency ◽  
Size Variability ◽  
Taxonomic Affiliation

Abstract Body size is a functional trait that influences the overall biology and ecology of an organism. Studying the shape of size–frequency distributions and size variability within different scales, approximates the influence of large-scale ecological and evolutionary processes on a species. In this study we examine the patterns of distribution and variability of body size among freshwater Cladocera across different taxonomic levels, geographic distribution and habitat association. Using extensive literature data, we show the global distribution of body size in freshwater Cladocera. Hierarchical models were used to assess the effect of different categorical variables on size variability. Our results show that almost all size–frequency distributions were skewed right in all categories. The hierarchical model showed that taxonomic affiliation contributes the most to size variability in our dataset, suggesting that size might be a conserved trait. Large genera (≥1mm) have larger estimated variability compared to smaller genera. In general, our observations on size–frequency distributions and size variability show a brief insight in the varying advantages of adaptive body size in this group of organisms in both biology (physiology) and ecology (competition and co-existence). Thus, body size is a trait important to the survival and continuing evolution of Cladocera.

Intraspecific body size variability in soil organisms at a European scale: Implications for functional biogeography

2018 ◽  
Vol 32 (11) ◽  
pp. 2562-2570 ◽  
Author(s):  
Jonathan Bonfanti ◽  
Mickaël Hedde ◽  
Sophie Joimel ◽  
Paul Henning Krogh ◽  
Cyrille Violle ◽  
...  
Keyword(s):  
Body Size ◽  
Soil Organisms ◽  
Size Variability

Small-scale spatiotemporal variability in body size of two common carabid beetles

2014 ◽  
Vol 9 (5) ◽  
pp. 476-494 ◽  
Author(s):  
Eliška Baranovská ◽  
Michal Knapp
Keyword(s):  
Body Size ◽  
Larval Growth ◽  
Weather Conditions ◽  
Carabid Beetles ◽  
Spatiotemporal Variability ◽  
Small Scale ◽  
Winter Mortality ◽  
Poecilus Cupreus ◽  
Arable Field ◽  
Anchomenus Dorsalis

AbstractAdult body size is one of the most ecologically relevant quantitative traits that underlies many other life-history traits of particular organism. In insects, there is positive intraspecific relationship between body size and female fecundity. In this study small scale temporal and spatial and space variability in structural body size of Poecilus cupreus and Anchomenus dorsalis was investigated. The beetles were collected in four fields near Prague-Suchdol in autumn 2009 and 2010, and in spring 2010, 2011 and 2012. In both species structural body size was significantly affected by sex (females were the larger sex). In A. dorsalis structural body size was also significantly affected by arable field identity, overwintering (post-overwintering individuals collected in spring were larger in comparison to pre-overwintering individuals collected in autumn), sampling year, overwintering by year and arable field by year interactions. Our results suggest that spatiotemporal variation in environmental conditions experienced by A. dorsalis during larval growth resulted in differences in adult structural body size among particular fields and particular sampling years. In addition, mean structural body size in A. dorsalis was affected by overwintering, which was probably caused by size-specific winter mortality. Moreover, effect of overwintering varied among years, probably according to the specific weather conditions during a particular winter.

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