Sexual Size Dimorphism and Selection in the Wild in the Waterstrider Aquarius remigis: Lifetime Fecundity Selection on Female Total Length and Its Components

Evolution ◽  
1997 ◽  
Vol 51 (2) ◽  
pp. 467 ◽  
Author(s):  
Richard F. Preziosi ◽  
Daphne J. Fairbairn
Keyword(s):  
Sexual Size Dimorphism ◽  
Aquarius Remigis ◽  
Lifetime Fecundity ◽  
Size Dimorphism ◽  
Total Length ◽  
Female Total ◽  
Fecundity Selection ◽  
In The Wild

Sexual size dimorphism in a natural population of Callicorixa vulnerata (Hemiptera: Corixidae)

2001 ◽  
Vol 133 (3) ◽  
pp. 311-313 ◽  
Author(s):  
P. Nosil
Keyword(s):  
Natural Population ◽  
Body Length ◽  
Sexual Size Dimorphism ◽  
Large Body ◽  
Size Dimorphism ◽  
Fecundity Selection ◽  
Adaptive Processes ◽  
Males And Females ◽  
Spine Number ◽  
Water Boatmen

Sexual size dimorphism occurs in many species. Differences between males and females, in size or other characteristics, may result from sexual selection, fecundity selection, natural selection, non-adaptive processes, or a combination of these pressures (Darwin 1874; Selander 1966; Trivers 1976; Slatkin 1984; Shine 1989). In insects, females with large body size often produce more eggs than smaller females, and femalebiased sexual size dimorphism is commonly attributed to such fecundity selection (e.g., Preziosi and Fairbairn 1997; but see Leather 1988). Water boatmen are detrivorous or zoophagous aquatic insects often inhabiting small ponds of the Northern Hemisphere (Hungerford 1948; Nosil and Reimchen 2001). Female water boatmen are generally larger than males. In this note, I quantify the nature and magnitude of a previously undescribed sexual size dimorphism in a natural population of the water boatman Callicorixa vulnerata Uhler (Hemiptera: Corixidae). I tested for differences between males and females in mean trait size (body length, body weight, mid-leg tarsal length, mid-leg tarsal spine number), and also tested for sexual dimorphism in allometric relationships between tarsal traits and body length.

scholarly journals A unified-models analysis of the development of sexual size dimorphism in Damaraland mole-rats, Fukomys damarensis

2019 ◽  
Vol 100 (4) ◽  
pp. 1374-1386
Author(s):  
Jack Thorley ◽  
Tim H Clutton-Brock
Keyword(s):  
Sex Differences ◽  
Sexual Size Dimorphism ◽  
Growth Models ◽  
Growth Data ◽  
Size Dimorphism ◽  
Skeletal Size ◽  
In The Wild ◽  
Parameterized Family ◽  
Sigmoid Functions ◽  
Reliable Basis

AbstractIndividual variation in growth rates often generates variation in fitness. However, the ability to draw meaningful inferences from growth data depends on the use of growth models that allow for direct comparisons of growth between the sexes, between populations, and between species. Unlike traditional sigmoid functions, a recently parameterized family of unified growth models provides a reliable basis for comparisons since each parameter affects a single curve characteristic and parameters are directly comparable across the unified family. Here, we use the unified-models approach to examine the development of sexual size dimorphism in Damaraland mole-rats (Fukomys damarensis), where breeding males are larger than breeding females. Using skeletal measurements, we show here that the larger size of male Damaraland mole-rats arises from an increased growth rate across the entire period of development, rather than through sex differences in the duration or timing of growth. Male-biased skeletal size dimorphism is not unusual among rodents, and our measures of sex differences in size in captive mole-rats are close to sexual size differences in the wild, where size dimorphism = 1.04 (male:female). We hope our study will encourage the wide use of unified growth models by mammalogists.

Sign in / Sign up

Export Citation Format

Share Document