The size and shape of parasitic larvae of naiads (Unionidae) are not dependent on female size

AbstractThe naiads, large freshwater mussels (Unionida), have very long life spans, are large-bodied, and produce thousands to millions of larvae (glochidia) which typically must attach to host fish tissues to metamorphose into a juvenile mussel. Glochidia develop within a female's marsupial gill demibranch, thus their number is restricted by female size. However, larger mussels acquire more energy, which could be invested in either larger-sized glochidia, in a more glochidia, or a combination of both. The high level of host specialization seen in many naiads may constrain glochidial size and shape around a narrow optimum, while naiads that use a wide range of host fishes may be predicted to possess greater plasticity in glochidial morphology. In this paper, we investigated the relationship between maternal body size and progeny body size and shape, aided by modern digital microscopy. We analyzed the between- and within- species variation of glochidia size and shape relative to female size in four widespread species of European naiads: Anodonta anatina, Anodonta cygnea, Unio crassus and Unio tumidus. Whereas the total reproductive output is collinear with female body size, substantial differences between species in glochidia size were found within genus Anodonta, but not genus Unio where glochidial size is remarkably consistent. The glochidial shape, however, differed within both Unio and Anodonta. We interpret this constant within-species glochidial size in Unio as reflecting a constraint imposed by the likelihood of successful transmission onto and off from a narrow range of hosts, whereas their shape seems to be less constrained. The Anodonta species, inhabiting a wide spectrum of habitats and using more than twice the number of fish hosts than Unio spp., have larger glochidia with greater variation in size and shape. Our results suggest that measures of glochidial variability may also serve as an indicator of host specificity in other naiads.

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Investigating the link between television viewing and men's preferences for female body size and shape in rural Nicaragua

Evolution and Human Behavior ◽

10.1016/j.evolhumbehav.2018.05.005 ◽

2018 ◽

Vol 39 (5) ◽

pp. 538-546 ◽

Cited By ~ 3

Author(s):

Tracey Thornborrow ◽

Jean-Luc Jucker ◽

Lynda G. Boothroyd ◽

Martin J. Tovée

Keyword(s):

Body Size ◽

Female Body ◽

Television Viewing ◽

Size And Shape ◽

Female Body Size

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Monogamy in the European Starling

Behaviour ◽

10.1163/156853992x00633 ◽

1992 ◽

Vol 120 (3-4) ◽

pp. 262-285 ◽

Cited By ~ 25

Author(s):

Innes Cuthill ◽

Jonathan Wright

Keyword(s):

Body Size ◽

Experimental Studies ◽

Nest Defence ◽

Female Size ◽

European Starlings ◽

Male And Female ◽

Female Body Size ◽

Relative Contribution ◽

Provisioning Rate ◽

Male Display

AbstractRecent theoretical and experimental studies appear to provide a comprehensive explanation for the evolutionary, and short-term, stability of biparental care in birds. However, much of the intraspecific variation in the absolute and relative contribution by the male and female remains to be explained. Most studies of the natural variation across pairs reveal positive correlations between the level of male and female nest defence or brood provisioning, but some species show negative relations, or between-season variability in the direction of the relationship. This study examines the determinants of male and female provisioning rate in monogamous European starlings (Sturnus vulgaris), in terms of the patterns of male display, pairing patterns, laying phenology and clutch attributes. There was assortative pairing by body size and, controlling for female body size, larger males attracted relatively fecund mates. Males that sang relatively more, controlling for these body size effects, were paired with females that laid earlier. Female nest provisioning rates to experimentally standardized broods were positively correlated with female size, but male provisioning rates were unrelated to either song or any other attributes of themselves or their mates.

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Perceptions of Female Body Size and Shape in China, Hong Kong, and the United Kingdom

Cross-Cultural Research ◽

10.1177/1069397113510272 ◽

2013 ◽

Vol 48 (1) ◽

pp. 78-103 ◽

Cited By ~ 7

Author(s):

Josephine J. Y. Mo ◽

Kate W. K. Cheung ◽

Lucinda J. Gledhill ◽

Thomas V. Pollet ◽

Lynda G. Boothroyd ◽

...

Keyword(s):

Hong Kong ◽

United Kingdom ◽

Body Size ◽

Female Body ◽

Size And Shape ◽

Female Body Size ◽

The United Kingdom

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Egg burial depth by sockeye salmon (Oncorhynchus nerka): implications for survival of embryos and natural selection on female body size

Canadian Journal of Zoology ◽

10.1139/z99-020 ◽

1999 ◽

Vol 77 (5) ◽

pp. 836-841 ◽

Cited By ~ 44

Author(s):

Ryan P Steen ◽

Thomas P Quinn

Keyword(s):

Body Size ◽

Female Body ◽

Sockeye Salmon ◽

Oncorhynchus Nerka ◽

Female Size ◽

Burial Depth ◽

Female Body Size ◽

Substrate Level ◽

The Relationship ◽

Stream Bed

We studied the relationship between female sockeye salmon (Oncorhynchus nerka) body size and egg burial depth in a small Alaskan stream to better understand the ways in which stream-bed scour or digging by other females might destroy embryos. Two different measurements of egg burial depth were taken: depth from the original stream-bed surface to the top of the egg pocket and depth from the disturbed substrate directly above the egg pocket to the top of the egg pocket. The former may represent the depth to which stream-bed scouring would have to go to reach the eggs, but the latter represents the depth to which a second female would have to dig to disturb the egg pocket. Larger females buried their eggs deeper, relative to the original substrate level, than smaller females. This suggests that streams with frequent scour events would select for larger females. However, mean depth from the disturbed substrate level was significantly shallower than mean depth from the original stream-bed level, suggesting that even the smallest females could dig deep enough to disturb the egg pockets of the largest females. Finally, the egg burial depth - fish size relationship that we observed was compared with published data on other salmonid species, revealing considerable variation but a clear positive relationship between female size and burial depth. Because embryonic survival is affected by scour and nest disturbance, and because changes in fish body size, density, and flow regime can affect the vulnerability of embryos to such mortality, we recommend further, standardized measurements of the relationship between egg burial depth and female body size.

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Sexual dimorphism in Ephedrus persicae (Hymenoptera: Braconidae: Aphidiinae): intraspecific variation in size and shape

The Canadian Entomologist ◽

10.4039/n09-029 ◽

2009 ◽

Vol 141 (6) ◽

pp. 550-560 ◽

Cited By ~ 5

Author(s):

Ana Mitrovski Bogdanović ◽

Ana Ivanović ◽

Željko Tomanović ◽

Vladimir Žikić ◽

Petr Starý ◽

...

Keyword(s):

Sexual Dimorphism ◽

Intraspecific Variation ◽

Size Variation ◽

Wing Shape ◽

Species Variation ◽

Wing Size ◽

Aphid Parasitoid ◽

Size And Shape ◽

Variation Patterns ◽

Wide Range

AbstractSexual dimorphism in size and shape has been studied in a wide range of organisms, but intraspecific variation in sexual dimorphism remains largely unexplored. In many parasitoid species the diversity of morphological-variation patterns within species is complicated by host effects. It is not known whether the magnitude and direction of sexual size dimorphism can be affected by the developmental environment (i.e., different host species). In this study we explored patterns of sexual dimorphism in size and shape in the aphid parasitoid Ephedrus persicae Froggatt. The analyzed sample consisted of 83 females and 54 males reared from five species of host aphids (Hemiptera: Aphididae) from various areas of the Palaearctic region. The most notable result of the study is that E. persicae displays divergent patterns of sexual dimorphism in body size and wing size: females have larger bodies than males, but males have larger wings. Our analysis of wing size and wing shape also showed significant within species variation in the degree and pattern of sexual dimorphism. Variation in wing shape between the sexes seems to be more conserved than variation in wing size. Variation in wing shape is influenced predominantly by host (biotype) and to a lesser extent by sexual dimorphism within a biotype.

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Breeding traits of Hermann's tortoise Testudo hermanni hermanni in two western populations

Amphibia-Reptilia ◽

10.1163/156853807779798965 ◽

2007 ◽

Vol 28 (1) ◽

pp. 77-85 ◽

Cited By ~ 10

Author(s):

Marc Cheylan ◽

Jean Pierre Nougarède ◽

Aurelio Marín ◽

Albert Bertolero

Keyword(s):

Body Size ◽

Clutch Size ◽

Female Body ◽

Egg Production ◽

Reproductive Traits ◽

Ebro Delta ◽

Female Size ◽

Female Body Size ◽

Testudo Hermanni ◽

Testudo Hermanni Hermanni

AbstractOver a period of two years we used radiology to investigate breeding traits in females of two western populations of the threatened Hermann's tortoise Testudo hermanni hermanni. The main purpose of the study was to see if reproductive traits – clutch size, clutch frequency, annual egg production and egg width – varied between populations in Corsica (France) and the Ebro Delta (Spain), and if these traits were affected by female body size and amounts of spring rainfall. All the breeding traits analysed were greater in the Corsican population than in the Ebro Delta population. These differences were also significant when we used female body size as a covariable. In both populations the amount of spring rainfall affected breeding traits but not clutch size. Nevertheless, only in the Corsican population did clutch frequency, annual egg production and egg width increase significantly in the year with a wet spring. Contrary to the predictions of Optimal Propagule Size theory, we found that egg size and clutch size increased with female size, and that both variables were independent. On the other hand, clutch frequency was not related to female body size. Thus, in the Hermann's tortoise, as clutch size did not change between years and clutch frequency was independent of female size, all females are able to increase their reproductive output in years with favourable conditions by increasing their clutch frequency. Nevertheless, other factors besides female size and rainfall may influence in a highly complex way variability in breeding traits among populations.

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Golden Orbweavers Ignore Biological Rules: Phylogenomic and Comparative Analyses Unravel a Complex Evolution of Sexual Size Dimorphism

10.1101/368233 ◽

2018 ◽

Cited By ~ 3

Author(s):

Matjaž Kuntner ◽

Chris A. Hamilton ◽

Cheng Ren-Chung ◽

Matjaž Gregorič ◽

Nik Lupše ◽

...

Keyword(s):

Body Size ◽

Female Body ◽

Sexual Size Dimorphism ◽

Female Size ◽

Male And Female ◽

Size Dimorphism ◽

Female Body Size ◽

Size Evolution ◽

Web Size ◽

Cope’S Rule

AbstractInstances of sexual size dimorphism (SSD) provide the context for rigorous tests of biological rules of size evolution, such as Cope’s Rule (phyletic size increase), Rensch’s Rule (allometric patterns of male and female size), as well as male and female body size optima. In certain spider groups, such as the golden orbweavers (Nephilidae), extreme female-biased SSD (eSSD, female:male body length ≥ 2) is the norm. Nephilid genera construct webs of exaggerated proportions which can be aerial, arboricolous, or intermediate (hybrid). First, we established the backbone phylogeny of Nephilidae using 367 Anchored Hybrid Enrichment (AHE) markers, then combined these data with classical markers for a reference species-level phylogeny. Second, we used the phylogeny to test Cope and Rensch’s Rules, sex specific size optima, and the coevolution of web size, type, and features with female and male body size and their ratio, SSD. Male, but not female, size increases significantly over time, and refutes Cope’s Rule. Allometric analyses reject the converse, Rensch’s Rule. Male and female body sizes are uncorrelated. Female size evolution is random, but males evolve towards an optimum size (3.2–4.9 mm). Overall, female body size correlates positively with absolute web size. However, intermediate sized females build the largest webs (of the hybrid type), giant female Nephila and Trichonephila build smaller webs (of the aerial type), and the smallest females build the smallest webs (of the arboricolous type). We propose taxonomic changes based on the criteria of clade age, monophyly and exclusivity, classification information content, diagnosability, and arachnological community practice. We resurrect the family Nephilidae Simon 1894 that contains Clitaetra Simon 1889, the Cretaceous Geratonephila Poinar & Buckley 2012, Herennia Thorell 1877, Indoetra Kuntner 2006, new rank, Nephila Leach 1815, Nephilengys L. Koch 1872, Nephilingis Kuntner 2013, and Trichonephila Dahl 1911, new rank. We propose the new clade Orbipurae to contain Araneidae Clerck 1757, Phonognathidae Simon 1894, new rank, and Nephilidae. Nephilid female gigantism is a phylogenetically-ancient phenotype (over 100 ma), as is eSSD, though their magnitudes vary by lineage and, to some extent, biogeographically.

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Reproductive aspects of the shrimp Cuapetes americanus (Kingsley, 1878) (Caridea, Palaemonidae) from Bocas del Toro, Panama

Crustaceana ◽

10.1163/15685403-00003685 ◽

2017 ◽

Vol 90 (7-10) ◽

pp. 1061-1078 ◽

Cited By ~ 1

Author(s):

Mariana Negri ◽

Tatiana Magalhães ◽

Natália Rossi ◽

Darryl L. Felder ◽

Fernando L. Mantelatto

Keyword(s):

Body Size ◽

Female Body ◽

Reproductive Output ◽

Reproductive Traits ◽

The Body ◽

Female Size ◽

Energy Investment ◽

Western Atlantic ◽

Bocas Del Toro ◽

Female Body Size

The shrimpCuapetes americanusis widely distributed in shallow waters of the western Atlantic Ocean, inhabiting sandy and rocky bottoms, macroalgae, seagrass beds, and mangrove roots. As the life cycle and ecology of this species remain poorly known, we investigated some reproductive traits of this species at Bocas del Toro, Panama. We collected and examined 167 individuals (63 males, 58 non-ovigerous females and 46 ovigerous females). Although males numerically dominated the larger size classes, ovigerous females were significantly larger than males and non-ovigerous females. All 46 ovigerous females were used to calculate embryo loss and embryo volume increase. Only females with eggs at an initial developmental stage () were used to estimate fecundity and reproductive output. A mean of 75.84 ± 40.16 embryos () occurred per female, a value near those reported for other species of Pontoniinae. A positive correlation between fecundity and female body size was observed, but it lacked significance. Likewise, a significant correlation between female body size and embryo volume was not detected. Embryo volume increased 35%, and females lost 26% of embryos on average during the incubation period, though significant changes were measurable only during early embryonic development. Mean reproductive output in the analysed reproductive event (0.22 ± 0.11, ) suggested a rate of energy investment in reproduction higher than average, as compared to females of most other decapods. A decrease in relative reproductive output was observed with the increase of female size, indicating that larger females were investing proportionally less energy in reproduction than smaller ones, when measured in relation to the body size, but this correlation also lacked significance. We review how these initial insights on reproduction ofC. americanusat Bocas del Toro compare to those of other populations in various localities.

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Reproduction triggers adaptive increases in body size in female mole-rats

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.0897 ◽

2018 ◽

Vol 285 (1880) ◽

pp. 20180897 ◽

Cited By ~ 7

Author(s):

Jack Thorley ◽

Nathan Katlein ◽

Katy Goddard ◽

Markus Zöttl ◽

Tim Clutton-Brock

Keyword(s):

Body Size ◽

Lumbar Vertebrae ◽

Growth Patterns ◽

Group Setting ◽

Reproductive Suppression ◽

Size And Shape ◽

Female Body Size ◽

Socially Responsive ◽

Natural Groups ◽

Breeding Status

In social mole-rats, breeding females are larger and more elongated than non-breeding female helpers. This status-related morphological divergence is thought to arise from modifications of skeletal growth following the death or removal of the previous breeder and the transition of their successors from a non-breeding to a breeding role. However, it is not clear what changes in growth are involved, whether they are stimulated by the relaxation of reproductive suppression or by changes in breeding status, or whether they are associated with fecundity increases. Here, we show that, in captive Damaraland mole-rats ( Fukomys damarensis ), where breeding was experimentally controlled in age-matched siblings, individuals changed in size and shape through a lengthening of the lumbar vertebrae when they began breeding. This skeletal remodelling results from changes in breeding status because (i) females removed from a group setting and placed solitarily showed no increases in growth and (ii) females dispersing from natural groups that have not yet bred do not differ in size and shape from helpers in established groups. Growth patterns consequently resemble other social vertebrates where contrasts in size and shape follow the acquisition of the breeding role. Our results also suggest that the increases in female body size provide fecundity benefits. Similar forms of socially responsive growth might be more prevalent in vertebrates than is currently recognized, but the extent to which this is the case, and the implications for the structuring of mammalian dominance hierarchies, are as yet poorly understood.

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