Scaling of sexual dimorphism in body size and breeding system in primates

Section: Methodsmentioning

confidence: 99%

Sexual size dimorphism and corroboration of Rensch’s rule in Chersastus millipedes (Diplopoda: Pachybolidae)

Cooper¹

2014

“…Isometry for sexual size dimorphism (SSD) is based on the general allometric model [12][13] , male size = α (female size) β ; correlation coefficient, r = 0.85. The regression of log (female size) on log (male size) would generate an identical relationship with β < 1.…”

Section: Figmentioning

confidence: 99%

Relative sexual size dimorphism in Centrobolus fulgidus (Lawrence) compared to 18 congenerics

Cooper¹

2017

The present research was aimed to study relative sexual size dimorphism of Centrobolus fulgidus (Lawrence) compared to 18 congenerics. Millipedes illustrate reversed sexual size dimorphism (SSD) as females are larger than males; and corroborate Rensch's rule as this dimorphism increases with body size. SSD was calculated in 18 species of the genus Centrobolus and illustrated as a regression. The approximate relative position of C. fulgidus was shown from measurements taken at Richards Bay Minerals (February 1996) and St. Lucia Estuary (December 1996) in South Africa. The size of C. fulgidus was 56.2 X 5.4 mm: 63.5 X 5.2 mm (males: females; n=11) and logged (x = 3.398; y = 3.301). The mean volume ratio for C. fulgidus was 1.2505. The evidence suggests the proximate cause for SSD in C. ruber is sexual bimaturism while the ultimate cause in Centrobolus is intersexual competition.

“…Sexual size dimorphism is visible with the naked eye (Figures 2 & 3). β [6][7] . Allometric coefficient, β < 1 (hypoallometric); correlation coefficient, r = 0.85.…”

Section: Resultsmentioning

confidence: 99%

“…Size was perceived as body volume and calculated based on the formula for a cylinder (l.π.r ) where l is body length and r half of the width. SSD was estimated as the mean female volume divided by mean male volume and converted into a SSD index by subtracting 1 Allometry for SSD was based on a general allometric model where male size = α (female) β [6] . Millipede SSD was thus calculated in the genus Centrobolus [1] .…”

Section: Methodsmentioning

confidence: 99%

The relative sexual size dimorphism of Centrobolus inscriptus compared to 18 congenerics

Cooper¹

2016

Millipedes illustrate reversed sexual size dimorphism (SSD) as females are larger than males. SSD was calculated in 18 species of the genus Centrobolus and illustrated as a regression. The approximate relative position of C. inscriptus is shown. The size of C. inscriptus was 2245mm 3 : 1841 mm 3 : (females: males; n=88) and logged (x = 3.351216; y = 3.265054) and plotted. The mean volume ratio for C. inscriptus was 1.219446. Sexual size dimorphism was visible with the naked eye.