Latitudinal variation in egg and clutch size in turtles

1993 ◽  
Vol 71 (12) ◽  
pp. 2448-2461 ◽  
Author(s):  
John B. Iverson ◽  
Christine P. Balgooyen ◽  
Kathy K. Byrd ◽  
Kelly K. Lyddan
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Egg Size ◽  
Positive Relationship ◽  
Negative Relationship ◽  
Latitudinal Variation ◽  
Significant Negative Relationship ◽  
Latitudinal Patterns ◽  
Clutch Mass ◽  
Size Data

Reproductive and body size data from 169 populations of 146 species (56% of those recognized), 65 genera (75%), and 11 families (92%) of turtles were tabulated to test for latitudinal variation in egg and clutch size. Body-size-adjusted correlation analysis of all populations (as well as within most families) revealed (i) a significant negative relationship (r2 = 0.26) between latitude and egg size, (ii) a significant positive relationship (r2 = 0.21) between latitude and clutch size, and (iii) no relationship between latitude and clutch mass. Phylogenetic contrast analyses corroborated these patterns. Clutch size was also negatively correlated with egg size across all populations as well as within most families. We evaluate the applicability to turtles of hypotheses postulated to explain such latitudinal patterns for other vertebrate groups. The observed pattern may be the result of latitudinal variation in selection on egg size and (or) clutch size, as well as on the optimal trade-off between these two traits.

THE WING LENGTH OF SWELTSA REVELSTOKA (PLECOPTERA: CHLOROPERLIDAE)

1985 ◽  
Vol 117 (2) ◽  
pp. 233-239 ◽  
Author(s):  
D.B. Donald
Keyword(s):  
Body Size ◽  
Significant Relationship ◽  
Positive Relationship ◽  
Wing Length ◽  
Negative Relationship ◽  
Head Capsule ◽  
High Elevation ◽  
Glacial Ice ◽  
Significant Negative Relationship ◽  
Stream Size

AbstractFunctional wing length (wing length/head-capsule width) of female Sweltsa revelstoka (Jewett) from streams was measured for 19 sites that have been free of Wisconsin glacial ice for about 15 000 years and possibly longer, and from 23 sites that have been ice free for about 10 000 years. At the former sites brachypterous populations were common and there was a significant negative relationship between functional wing length and elevation, and a positive relationship between functional wing length and stream size. In the area that deglaciated more recently, populations were not or only slightly brachypterous and there was no significant relationship between wing length and elevation or between wing length and stream size. Functional wing length was not related to body size. These analyses indicate that the brachypterous condition is probably genotypic in origin. I suggest that streams were colonized by macropterous forms shortly after deglaciation, and that brachyptery takes several millennia to develop at small, high-elevation streams.

Annual variations in reproductive characteristics of painted turtles (Chrysemys picta)

1986 ◽  
Vol 64 (5) ◽  
pp. 1148-1151 ◽  
Author(s):  
Lin Schwarzkopf ◽  
Ronald J. Brooks
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Repeated Measures ◽  
Egg Size ◽  
Annual Variation ◽  
Egg Mass ◽  
Annual Variations ◽  
Painted Turtles ◽  
Sources Of Variation ◽  
Clutch Mass

In Algonquin Park, Ontario, body size and clutch characteristics were recorded for 51 female painted turtles (Chrysemyspicta) in 1983, 61 in 1984, and 24 in 1985. Clutch size, clutch mass, and egg width correlated significantly with body size (carapace length) in all 3 years. Egg length and egg mass were significantly related to body size in 1984 and 1985, but not in 1983. There were no significant correlations of egg width or egg mass to clutch size. For a group of the same individuals compared by repeated-measures ANOVA, mean clutch mass and mean egg size, but not mean clutch size, varied significantly among years. Correlation of egg size with body size, lack of correlation between egg size and clutch size, and annual variation in egg size, but not clutch size, all fail to support current versions of optimal egg size theory. Twenty-six females nested in both 1983 and 1984 and 11 females nested in both 1984 and 1985. Fourteen females nested twice in 1 year: six in 1983 and eight in 1984. Between 43 and 73% of adult females nested in a given year and 12–13% nested twice in a single season. These estimates are similar to those reported for other populations of this species. It appears that variations in both clutch size (frequency) and egg size are important sources of variation in reproductive output.

Growth and body size in Blanding's turtles (Emydoidea blandingi): relationships to reproduction

1991 ◽  
Vol 69 (1) ◽  
pp. 239-245 ◽  
Author(s):  
Justin D. Congdon ◽  
Richard C. van Loben Sels
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Egg Size ◽  
Reproductive Output ◽  
Body Sizes ◽  
Minimum Age ◽  
Average Size ◽  
Average Body ◽  
Clutch Mass ◽  
Growth And Reproduction

Growth and reproduction in Blanding's turtles (Emydoidea blandingi) were studied in southeastern Michigan from 1975 through 1988. Average body sizes of both sexes of adults were similar; however, shapes of males were different from those of females. The average size of a group of females with a mean minimum age of 47 years was not significantly different from a younger group with a mean age of 21 years. Clutch size ranged from 3 to 19 ([Formula: see text], N = 280) eggs over 11 years. Clutch wet mass ranged from 60.4 to 183.4 g ([Formula: see text], N = 17), and relative clutch mass of nine females averaged 0.12. Clutch size, and to a lesser degree egg size, showed a significant positive relationship with body size, but not with age of females. Hatchlings averaged 31.0 mm in plastron length, 35.3 mm in carapace length, and 9.2 g in body wet mass. Differences in juvenile growth rates and age at sexual maturity appear to be the major cause of variation in body size of adult Blanding's turtles and the related reproductive output per clutch.

Body size effects on pursuit success and interspecific diet differences in Cnemidophorus lizards

2000 ◽  
Vol 21 (4) ◽  
pp. 477-484 ◽  
Author(s):  
Kelly Passek ◽  
Douglas Eifler
Keyword(s):  
Body Size ◽  
Positive Relationship ◽  
Negative Relationship ◽  
Significant Positive Relationship ◽  
Significant Negative Relationship ◽  
Experimental Feeding ◽  
Feeding Trials ◽  
The Mean ◽  
The Relationship ◽  
Cnemidophorus Uniparens

AbstractWe examined the relationship between body size and pursuit success in the lizard Cnemidophorus uniparens. Using grasshoppers as prey in experimental feeding trials, we found a significant positive relationship between lizard body size and pursuit time. In addition, larger individuals were significantly more likely to be unsuccessful at capturing the grasshoppers. We also examined the relationship between the mean body size of Cnemidophorus populations and diet composition. We found a significant negative relationship between mean body size and the proportion of grasshoppers in the diet and a significant positive relationship between mean body size and the proportion of termites in the diet.

Egg size and shape, clutch dynamics, and reproductive effort in European tortoises

1988 ◽  
Vol 66 (7) ◽  
pp. 1527-1536 ◽  
Author(s):  
A. Hailey ◽  
N. S. Loumbourdis
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Egg Production ◽  
Egg Size ◽  
Reproductive Effort ◽  
Energy Content ◽  
The Body ◽  
Female Reproduction ◽  
Northern Greece ◽  
Clutch Mass

Energetic aspects of female reproduction are described for the tortoises Testudo graeca, Testudo marginata, and Testudo hermanni (three populations of different body size) from northern Greece. Egg width increased with body size in some populations, but smaller individuals produced more elongate eggs, and egg weight was not related to body size. This method for overcoming the constraint of the width of the pelvic canal means that egg width is a poor measure of egg size. Clutch size, clutch mass, and annual egg production varied with body size between populations. Mean relative clutch mass ranged from 4 to 7%, and was highest in the three populations of T. hermanni. All populations laid two or three clutches per year, based on the total number of eggs and large follicles divided by clutch size. Multiple clutches reflect the morphological constraint of packing shelled eggs within the body, rather than energy accumulation during the nesting period. Material for reproduction was stored in growing follicles rather than fat bodies; follicles reached half of their final weight before the animals entered hibernation. Annual reproductive effort as a proportion of body energy content was about 15% in all populations. This is lower than in other reptiles, partly because the carapace accounts for over half of the total ash-free dry weight of the tortoise body.

Organization-Based Self-Esteem Affects Employees' Exchange Relationship Perceptions and Extrarole Behavior

2016 ◽  
Vol 44 (3) ◽  
pp. 509-517 ◽  
Author(s):  
Yanhan Zhu
Keyword(s):  
Social Exchange ◽  
Positive Relationship ◽  
Mainland China ◽  
Negative Relationship ◽  
Self Esteem ◽  
Moderating Effect ◽  
Exchange Relationship ◽  
Significant Positive Relationship ◽  
Significant Negative Relationship ◽  
Practical Implications

The 2 types of exchange relationship perceptions—social exchange relationship perceptions (SERPs) and economic exchange relationship perceptions (EERPs)—constitute the primary concept for understanding individual behavior in the workplace. Using a sample of 581 employees from Mainland China, I explored the effects of SERPs and EERPs on employee extrarole behavior (ERB), as well as the moderating effect of organization-based self-esteem (OBSE) on the relationships between SERPs and ERB, and between EERPs and ERB. The results revealed a significant positive relationship between SERPs and ERB, a significant negative relationship between EERPs and ERB, and a significant moderating effect for OBSE. Theoretical and practical implications of these findings are discussed.

Financial Performance Analysis of Nepalese Financial Institutions in the Framework of CAMEL

2020 ◽  
Vol 9 (1) ◽  
pp. 56-74
Author(s):  
Kedar Raj Gautam
Keyword(s):  
Financial Performance ◽  
Financial Institutions ◽  
Commercial Banks ◽  
Positive Relationship ◽  
Negative Relationship ◽  
Capital Adequacy ◽  
Significant Positive Relationship ◽  
Management Efficiency ◽  
Significant Negative Relationship ◽  
Development Banks

Analysis of financial performance to detect financial health of finance companies, development banks and commercial banks as a whole is a less explored research in Nepalese context. This paper, therefore, attempts to examine the financial performance and factors influencing financial performance of Nepalese financial depositary institutions in the framework of CAMEL. This study is based on descriptive cum casual research design. This study is based on secondary data which was extracted from various publications published by Nepal Rastra Bank such as banking and financial statistics, financial stability report and bank supervision report. All commercial banks, development banks, and finance companies are taken as population of the study. The study deals with financial performance analysis of entire population covering five years from 2014/15 to 2018/19. The variables such as capital adequacy, assets quality, management efficiency, earnings and liquidity are used to analyze financial performance. Descriptive as well as pooled regression analysis was used to assess the relationship among the variables. Descriptive analysis shows that financial institutions in each category meet NRB standard regarding capital adequacy. On the basis of capital adequacy and earnings, finance companies stand at first, on the basis of assets quality, development banks stand at first and on the basis of management efficiency, commercial banks stand at first. Finance companies store high liquidity as compared to other class financial institutions. The regression analysis shows that return on assets, ROA has significant positive relationship with capital adequacy and ROE but ROA has significant negative relationship with assets quality. However, return on equity, ROE has significant positive relationship with assets quality and ROA but ROE has significant negative relationship with capital adequacy. Capital adequacy and assets quality play major role to maximize ROA and ROE of financial institutions.

Clutch Mass, Offspring Mass, and Clutch Size: Body Mass Scaling and Taxonomic and Environmental Variation

2018 ◽  
pp. 68-97
Author(s):  
Douglas S. Glazier
Keyword(s):  
Life History ◽  
Body Size ◽  
Clutch Size ◽  
Body Mass ◽  
Life History Evolution ◽  
Offspring Size ◽  
Egg Mass ◽  
Mass Scaling ◽  
Scaling Relationships ◽  
Clutch Mass

In this chapter, I show how clutch mass, offspring (egg) mass, and clutch size relate to body mass among species of branchiopod, maxillipod, and malacostracan crustaceans, as well as how these important life history traits vary among major taxa and environments independently of body size. Clutch mass relates strongly and nearly isometrically to body mass, probably because of physical volumetric constraints. By contrast, egg mass and clutch size relate more weakly and curvilinearly to body mass and vary in inverse proportion to one another, thus indicating a fundamental trade-off, which occurs within many crustacean taxa as well. In general, offspring (egg) size and number and their relationships to body mass appear to be more ecologically sensitive and evolutionarily malleable than clutch mass. The body mass scaling relationships of egg mass and clutch size show much more taxonomic and ecological variation (log-log scaling slopes varying from near 0 to almost 1 among major taxa) than do those for clutch mass, a pattern also observed in other animal taxa. The curvilinear body mass scaling relationships of egg mass and number also suggest a significant, size-related shift in how natural selection affects offspring versus maternal fitness. As body size increases, selection apparently predominantly favors increases in offspring size and fitness up to an asymptote, beyond which increases in offspring number and thus maternal fitness are preferentially favored. Crustaceans not only offer excellent opportunities for furthering our general understanding of life history evolution, but also their ecological and economic importance warrants further study of the various factors affecting their reproductive success.

scholarly journals Farmers’ perception of beneficial effects and limitations of vermicompost

2018 ◽  
Vol 5 (1) ◽  
pp. 19-25
Author(s):  
Md Shiduzzaman ◽  
Humyra Akhter ◽  
Mohammad Bashir Ahmed ◽  
Md Matiul Islam
Keyword(s):  
Positive Relationship ◽  
Negative Relationship ◽  
Training Experience ◽  
Interview Schedule ◽  
Beneficial Effects ◽  
Significant Negative Relationship ◽  
Spss Software ◽  
The Relationship ◽  
Day By Day ◽  
Scale Data

Vermicompost is very useful manure which is becoming popular day by day. However, its perception by the farmers is not yet assessed in the southwestern region of Bangladesh. The main objectives of this study were to determine the farmers’ perception of beneficial effects and limitations of vermicompost and to explore the relationship between selected characteristics of the farmers’ and their perception of beneficial effects and limitations of vermicompost. Data were collected using an interview schedule from randomly selected 60 respondents. Locale was three villages namely Lokhpur, Bollokhpur and Vobna under Fakirhat upazila of Bagerhat district. Faceto- face interview was conducted during 7 to 29 May, 2016. Farmers’ perception regarding the beneficial effects and limitations of vermicompost was measured using 5- point Likert type scale. Data were analyzed using SPSS software and farmers’ perception index was calculated. Majority (66.7 percent) of the respondents had moderate perception while 18.3 percent and 15 percent of them had less and high perception, respectively, on the beneficial effects and limitations of vermicompost. Among seven selected characteristics of the respondents, age showed a significant negative relationship with their perception of beneficial effects and limitations of vermicompost while training experience of the respondents showed a significant positive relationship with their overall perception. Thus, arrangement of training could pave the way of high perception of beneficial effects and limitations of vermicompost.Res. Agric., Livest. Fish.5(1): 19-25, April 2018

Clutch and egg size of the tropical lizard Tropidurus torquatus (Tropiduridae) along its geographic range in coastal eastern Brazil

2008 ◽  
Vol 86 (12) ◽  
pp. 1376-1388 ◽  
Author(s):  
M. C. Kiefer ◽  
M. Van Sluys ◽  
C. F.D. Rocha
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Female Body ◽  
Egg Size ◽  
Reproductive Investment ◽  
Geographic Range ◽  
Minimum Size ◽  
Brazilian Coast ◽  
Female Body Size ◽  
Almost All

The tropidurid lizard Tropidurus torquatus (Wied, 1820) has a set of populations inhabiting coastal sand dune habitats (“restinga”) along the eastern Brazilian coast. Despite its wide geographic range, there is no information about geographic variation in reproductive features among its populations. In the present study we compared some reproductive aspects of females in 10 coastal populations of T. torquatus, aiming to evaluate to what extension they vary geographically. The minimum size at maturity was relatively similar to most populations, but mean female body size had a considerable variation. Clutch size of almost all coastal populations of T. torquatus had little variation and was composed predominantly of two eggs. Interpopulational variation in the mean egg volume was relatively wide and strongly influenced by the variation in mean female body size. The data of the present study indicated that females of almost all coastal populations of T. torquatus produce, predominantly, clutches with two eggs and invest more energy in egg size instead of clutch size, probably as a consequence of morphological and environmental factors. The increased reproductive investment in egg size was confirmed by the values obtained for the relative clutch mass, which remained relatively constant along the coastal geographic distribution of T. torquatus.

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