Larval density and the Charnov–Bull model of adaptive environmental sex determination in a copepod

2005 ◽  
Vol 83 (7) ◽  
pp. 943-954 ◽  
Author(s):  
Maarten J Voordouw ◽  
H Eve Robinson ◽  
Gabe Stebbins ◽  
Arianne Y.K Albert ◽  
Bradley R Anholt
Keyword(s):  
Body Size ◽  
Sex Determination ◽  
Larval Density ◽  
Specific Pattern ◽  
Male Body ◽  
Weak Effect ◽  
Environmental Sex Determination ◽  
Adult Body Size ◽  
Female Body Size ◽  
Adult Body

Charnov and Bull suggested that environmentally induced variation in adult body size coupled with sex-specific differences in fitness can select for the evolution of adaptive environmental sex determination (ESD). In this study we determine whether larval density affects sex determination in the copepod Tigriopus californicus (Baker, 1912), as predicted by Charnov and Bull. Individuals reared at low densities developed faster and were significantly larger than siblings reared at high densities. For these laboratory-reared individuals, sexual selection on male body size was stronger than fecundity selection on female body size, but this sex-specific pattern of selection was reversed in the field. Differences in food availability (for females) and the mode of competition (for males) may account for the conflicting results between laboratory and field. We found a weak effect of larval density on sex determination in a pilot experiment but no effect in a second, more powerful experiment. While larval density did not affect the sex ratio of T. californicus, our sex-specific estimates of selection on adult body size will inform future models of adaptive ESD in this species and other copepods.

Grass-flower thrips of the genus Chirothrips (Thysanoptera: Thripidae), with a key to species from Iran

Zootaxa ◽  
2010 ◽  
Vol 2411 (1) ◽  
pp. 33 ◽  
Author(s):  
KAMBIZ MINAEI ◽  
LAURENCE MOUND
Keyword(s):  
Body Size ◽  
Species Group ◽  
Identification Key ◽  
Key To Species ◽  
Adult Body Size ◽  
Flower Thrips ◽  
New Synonym ◽  
Adult Body ◽  
Structural Differences

Species of the genus Chirothrips Haliday breed and pupate only within grass florets. Each larva is restricted to a single floret, and adult body size is thus presumably related to floret size. Despite this, some Chirothrips species are distinguished only on states that are related to body size. The validity of some commonly recorded members of the C. manicatus species-group, including C. africanus and C. pallidicornis, is therefore considered questionable. Character states that have been used to define the genus Agrostothrips Hood are shown to be variable, and this genus is placed as a new synonym of Chirothrips. An identification key, based on illustrated structural differences, is provided to the Chirothrips known from Iran: C. aculeatus, C. atricorpus, C. kurdistanus, C. manicatus, C. meridionalis and C. molestus.

scholarly journals Childhood retardation resulting in reduction of adult body size due to lesser adolescent skeletal delay

1970 ◽  
Vol 33 (3) ◽  
pp. 325-336 ◽  
Author(s):  
A. Roberto Frisancho ◽  
Stanley M. Garn ◽  
Werner Ascoli
Keyword(s):  
Body Size ◽  
Adult Body Size ◽  
Adult Body

Geographical and latitudinal variation in growth patterns and adult body size of Swedish moose (Alces alces)

Oecologia ◽  
1995 ◽  
Vol 102 (4) ◽  
pp. 433-442 ◽  
Author(s):  
H�kan Sand ◽  
G�ran Cederlund ◽  
Kjell Danell
Keyword(s):  
Body Size ◽  
Alces Alces ◽  
Growth Patterns ◽  
Latitudinal Variation ◽  
Adult Body Size ◽  
Adult Body

Evolutionary Divergence of Adult Body Size and Juvenile Growth in Sympatric Subpopulations of a Top Predator in Aquatic Ecosystems

2015 ◽  
Vol 186 (1) ◽  
pp. 98-110 ◽  
Author(s):  
Petter Tibblin ◽  
Anders Forsman ◽  
Per Koch-Schmidt ◽  
Oscar Nordahl ◽  
Peter Johannessen ◽  
...  
Keyword(s):  
Body Size ◽  
Aquatic Ecosystems ◽  
Evolutionary Divergence ◽  
Juvenile Growth ◽  
Top Predator ◽  
Adult Body Size ◽  
Adult Body

scholarly journals Associations between prenatal and postnatal growth and adult body size and composition

2003 ◽  
Vol 77 (6) ◽  
pp. 1498-1505 ◽  
Author(s):  
Haojie Li ◽  
Aryeh D Stein ◽  
Huiman X Barnhart ◽  
Usha Ramakrishnan ◽  
Reynaldo Martorell
Keyword(s):  
Body Size ◽  
Postnatal Growth ◽  
Adult Body Size ◽  
Adult Body

The role of thermal environment in determining the life history of a terrestrial salamander

2000 ◽  
Vol 78 (10) ◽  
pp. 1702-1711 ◽  
Author(s):  
Carlos D Camp ◽  
Jeremy L Marshall
Keyword(s):  
Body Size ◽  
Thermal Environment ◽  
Negative Relationship ◽  
Size Variation ◽  
Published Data ◽  
Size At Maturity ◽  
Adult Males ◽  
Age At Maturity ◽  
Adult Body Size ◽  
Adult Body

Largely using previously published data, we analyzed geographic variation in adult body size of terrestrial salamanders of the Plethodon glutinosus complex. Maximum body size of adult males is determined by size at maturity. In turn, size at maturity is determined by a negative relationship with environmental temperature. Moreover, both age at maturity and growth rate are correlated with size at maturity, but apparently only as coincidental correlates through the influence of temperature. The number of degree-days, estimated using temperature data from respective geographic locations, accurately predicts age at maturity for salamanders living in these areas. Development under cooler thermal regimes is more depressed than growth and, consequentially, adult body sizes are greater in cooler climates. This pattern of size variation fits thermal predictive models proposed for larval development in amphibians that breed in ponds. Phenotypic variation in adult body size appears to be accounted for largely by plastic responses to variation in thermal environments and may reflect a single reaction norm for the complex.

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