Comparative fecundity, clutch size, ovariole number and egg size of Dacus tryoni and D. jarvisi, and their relationship to body size

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.

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

Canadian Journal of Zoology ◽

10.1139/z08-106 ◽

2008 ◽

Vol 86 (12) ◽

pp. 1376-1388 ◽

Cited By ~ 17

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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Female reproductive characteristics of the Balkan wall lizard (Podarcis taurica) in the northwestern periphery of its range

Open Life Sciences ◽

10.2478/s11535-010-0016-2 ◽

2010 ◽

Vol 5 (3) ◽

pp. 391-395 ◽

Cited By ~ 4

Author(s):

Katarina Ljubisavljević ◽

Georg Džukić ◽

Miloš Kalezić

Keyword(s):

Body Size ◽

Clutch Size ◽

Breeding Season ◽

Egg Size ◽

Reproductive Traits ◽

Species Range ◽

Trade Off ◽

Female Body Size ◽

Female Reproductive Traits ◽

Gravid Females

AbstractWe present data on the female reproductive traits of the Balkan wall lizard in the Deliblato Sand, a large continental sandland in the Pannonian area in the northwestern periphery of the species range. The clutch and egg characteristics of the population were investigated on the basis of clutches laid in laboratory conditions by gravid females captured in one locality. Balkan wall lizards produced at least two clutches in a breeding season. Individual females laid clutches of commonly two (range 1–4) eggs. The female body size had no effect on clutch and egg size. There was no trade-off between egg size and clutch size.

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ISOMETRY OF EGG SIZE IN A TEXAS POPULATION OF THE TURTLE STERNOTHERUS ODORATUS THAT EXHIBITS A NEARLY FIXED CLUTCH SIZE

Journal of North American Herpetology ◽

10.17161/jnah.vi.13615 ◽

2020 ◽

pp. 13-17

Author(s):

Peter V. Lindeman

Keyword(s):

Body Size ◽

Clutch Size ◽

Egg Size ◽

Female Body Size ◽

Competing Demands ◽

Sternotherus Odoratus ◽

Central Texas ◽

Relationship Of ◽

The Relationship ◽

Anatomical Constraints

In evaluating optimal egg-size theory and the effects of anatomical constraints on egg size in turtles, pivotal questions concern the significance of the relationship of egg size to female body size and whether the relationship is isometric or hypoallometric. In a central Texas population of the kinosternid turtle Sternotherus odoratus in which clutch size of a sample of turtles was nearly fixed (seven of eight females had two eggs while the largest female had three eggs), there was an isometric increase in egg width with body size among the females with two-egg clutches and significantly reduced egg width in the largest female’s three-egg clutch. Allometric analyses of populations that exhibit little variation in clutch size, as well as analysis of modal clutch sizes in populations with more variable clutch sizes, both have the potential to further illuminate the competing demands of increasing egg size vs. increasing clutch size as females grow larger, enabling them to optimize their reproductive output as it increases with body size.

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Variations in the reproductive strategies of three populations of Phrynocephalus helioscopus in China

PeerJ ◽

10.7717/peerj.5705 ◽

2018 ◽

Vol 6 ◽

pp. e5705

Author(s):

Tao Liang ◽

Lu Zhou ◽

Wenfeng He ◽

Lirong Xiao ◽

Lei Shi

Keyword(s):

Body Size ◽

Clutch Size ◽

Reproductive Strategies ◽

Female Body ◽

Egg Size ◽

Reproductive Traits ◽

Breeding Period ◽

Female Body Size ◽

Trade Offs ◽

Morphological Constraint

Background Egg size and clutch size are key life history traits. During the breeding period, it is possible for females to increase their reproductive output either by increasing the number of eggs if the optimal egg size (OES) is maintained, or by increasing the allocation of energy to each egg. However, the strategies adopted are often influenced by animals’ morphology and environment. Methods Here, we examined variation in female morphological and reproductive traits, tested for trade-offs between egg size and clutch size, and evaluated the relationship between egg size and female morphology in three populations of Phrynocephalus helioscopus. Results Female body size, egg size, and clutch size were larger in the Yi Ning (YN) and Fu Yun (FY) populations than in the Bei Tun (BT) population (the FY and YN populations laid more, and rounder eggs). Egg size was independent of female body size in two populations (BT and FY), even though both populations had an egg-size/clutch size trade-off. In the YN population, egg size and clutch size were independent, but egg size was correlated with female body size, consistent with the hypothesis of morphological constraint. Conclusions Our study found geographical variation in body size and reproductive strategies of P. helioscopus. Egg size was correlated with morphology in the larger-bodied females of the YN population, but not in the smaller-bodied females of the BT population, illustrating that constraints on female body size and egg size are not consistent between populations.

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Male size does not correlate with fertilization success in two bufonid toads that show size-assortative mating

Current Zoology ◽

10.1093/czoolo/59.6.740 ◽

2013 ◽

Vol 59 (6) ◽

pp. 740-746 ◽

Cited By ~ 7

Author(s):

Xiao-Li Fan ◽

Zhi-Hua Lin ◽

Xiang Ji

Keyword(s):

Body Size ◽

Assortative Mating ◽

Clutch Size ◽

Egg Size ◽

Dry Mass ◽

Fertilization Success ◽

Male Body ◽

Mating Pattern ◽

Male Size ◽

Male Preference

Abstract We examined sexual size dimorphism (SSD), mating pattern, fertilization efficiency and female reproductive traits in two bufonid toads (Bufo gargarizans and Duttaphrynus melanostictus) to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gar-garizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficiencies on average were higher in B. gargarizans (95%) than in D. melanostictus (91%). Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects: (1) both showed size-assortative mating; (2) females did not tradeoff egg size against egg number; (3) male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length (SVL); and (4) the ratio of male to female SVL did not affect fertilization efficiency. Our data show that: (1) a female preference for large males is likely not important in terms of egg fertilization success; (2) a male preference for large females is likely important because larger females are more fecund; and (3) size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating.

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Latitudinal variation in egg and clutch size in turtles

Canadian Journal of Zoology ◽

10.1139/z93-341 ◽

1993 ◽

Vol 71 (12) ◽

pp. 2448-2461 ◽

Cited By ~ 77

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.

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A comparison of reproductive output of the Omei Treefrog (Rhacophorus omeimontis) between high and low elevations

Animal Biology ◽

10.1163/157075511x584218 ◽

2011 ◽

Vol 61 (3) ◽

pp. 263-276 ◽

Cited By ~ 8

Author(s):

Wen Bo Liao ◽

Xin Lu

Keyword(s):

Body Size ◽

Clutch Size ◽

Egg Size ◽

Reproductive Output ◽

Food Resource ◽

High Elevation ◽

Cold Climate ◽

Western China ◽

Major Influence ◽

Rhacophorus Omeimontis

AbstractElevation that results in changes in climate, duration of breeding season and food resource has long been considered a major influence on the evolution of life-history traits in amphibians. The present study examined differences in reproductive output (clutch size and egg size) of the Omei Treefrog (Rhacophorus omeimontis) at two elevations (1000 m and 1700 m above sea level) in Baoxing County, western China. Within each population, female attributes (size and age) were responsible for much of the reproductive output variation in that larger or older females produced larger clutches of smaller eggs. Clutch size and egg size showed a significantly negative correlation, which was indicative of a trade-off between the two parameters. The high-elevation females were significantly larger than the low-elevation counterparts. After accounting for interpopulational difference in body size, clutch size, egg size and clutch volume differed significantly between the populations. For the high-elevation population relatively smaller clutches tended to be associated with larger eggs. Our findings suggest that females produce smaller clutches relative to body size and larger eggs in the high-elevation population to ensure that each egg is adequately provisioned in the face of cold climate and short duration of development.

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

Canadian Journal of Zoology ◽

10.1139/z91-036 ◽

1991 ◽

Vol 69 (1) ◽

pp. 239-245 ◽

Cited By ~ 38

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.

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Contrasting reproductive strategies in a narrow latitude range: the case of D’Orbigny’s slider

Amphibia-Reptilia ◽

10.1163/15685381-00003122 ◽

2017 ◽

Vol 38 (4) ◽

pp. 425-434

Author(s):

Priscila Silva Lucas ◽

Alex Bager

Keyword(s):

Body Size ◽

Clutch Size ◽

Evolutionary Biology ◽

Egg Size ◽

Life History Theory ◽

Geographical Area ◽

Size Variation ◽

Reproductive Traits ◽

Maternal Body ◽

Trade Offs

Reproductive traits and the level of parental investment in offspring varies between individuals and species. These are central issues in life history theory and evolutionary biology. Maternal body size plays an important role in reproduction, and we usually observe variable investment in offspring by females. Thus, optimal egg size may not be reached in some populations or species. In this study, we tested if reproductive traits differed between populations of D’Orbigny’s slider in a specific geographical area in Brazil. We evaluated the relationship between reproductive traits to maternal body size and clutch size to egg size to determine possible trade-offs across populations. At the population level, maternal body size and reproductive traits of D’Orbigny’s slider were different even in geographically nearby areas. Maternal body size had a positive effect on clutch size, but not on egg size, except in the Arroio Grande population. Nevertheless, we did not observe a negative correlation between clutch and egg size in any population. Although maternal body size had effects in the different populations explaining most of the variation of clutch size, variation in egg size may be the result of decreased survival chances in unpredictable environments and possibly morphological constraints. The trade-off between egg size and number was not observed and this could be expected if resource availability and reproductive allocation by females vary greatly among individuals.

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