The sexual selection of endometriosis.

2021 ◽  
Author(s):  
Bernard Crespi ◽  
Natalie L. Dinsdale
Keyword(s):  
Sexual Selection ◽  
Selection Of

scholarly journals Artificial sexual selection alters allometry in the stalk-eyed fly Cyrtodiopsis dalmanni (Diptera: Diopsidae)

1993 ◽  
Vol 62 (3) ◽  
pp. 213-222 ◽  
Author(s):  
Gerald S. Wilkinson
Keyword(s):  
Sexual Selection ◽  
Sexual Dimorphism ◽  
Body Length ◽  
Sexually Dimorphic ◽  
Selected Lines ◽  
Variable Intensity ◽  
High Line ◽  
Cumulative Selection ◽  
Selection For ◽  
Selection Of

SummarySelection for increased and decreased ratio of eye span to body length was exerted on male stalk-eyed flies (Cyrtodiopsis dalmanni) from Malaysia using replicate selected and unselected lines. Response to selection was symmetrical. After 10 generations high line male eye span increased to 1·3 body lengths while low line male eye span declined to 1·1 body lengths. Realized heritabilities for eye span to body length ratio, estimated using regressions of deviations from unselected controls on cumulative selection differentials, were greater than zero for all four selected lines with average h2 = 0·35 + 0·06. The static linear allometric relationship between eye span and body length diverged between selected lines and rotated among selected line males in the same direction as among males in other sexually dimorphic diopsid species. Crosses between lines after 13 generations of selection indicate that the genes which influence relative eye span combine additively and do not exhibit sex linkage or maternal effects. The genetic correlation between the sexes, 0·29 + 0·05 as estimated by the regression of female on male change in eye span, did not prevent sexual dimorphism in eye span from diverging between lines. These results suggest that the exaggerated eye span of male C. dalmanni is maintained by natural selection opposing sexual selection rather than by lack of or asymmetry in additive genetic variation. Furthermore, the variation in sexual dimorphism for eye span-body length allometry observed among extant diopsid species is consistent with sexual selection of variable intensity acting on relative eye span.

Fighting success in relation to body mass and drumming activity in the male wolf spider Hygrolycosa rubrofasciata

1997 ◽  
Vol 75 (9) ◽  
pp. 1532-1535 ◽  
Author(s):  
Janne Kotiaho ◽  
Rauno V. Alatalo ◽  
Johanna Mappes ◽  
Silja Parri
Keyword(s):  
Sexual Selection ◽  
Body Mass ◽  
Wolf Spider ◽  
Male Body ◽  
Male Courtship ◽  
Hygrolycosa Rubrofasciata ◽  
Males And Females ◽  
A Minor ◽  
Selection Of ◽  
Agonistic Encounters

In the wolf spider Hygrolycosa rubrofasciata, males court females by drumming dry leaves with their abdomen. Females prefer to mate with the most actively drumming males, and courtship drumming activity is also positively correlated with male viability. However, body mass of the males seems to have only a minor, if any, effect on female choice or male viability. There is also no correlation between male body mass and courtship drumming activity. We studied the effect of body mass and courtship drumming activity on the outcome of agonistic encounters between male H. rubrofasciata. For this purpose, males and females were randomly placed in a plastic arena, where male courtship drumming activity and agonistic encounters were recorded. Large differences in body mass and drumming activity between two rivals seemed to independently increase the probability of the larger or more active males winning. We conclude that while courtship drumming activity affects the fighting success of the males, and body mass more so, male–male interactions may not be of major importance in sexual selection of H. rubrofasciata.

1. Darwin’s other big idea

2018 ◽  
pp. 1-15 ◽  
Author(s):  
Leigh W. Simmons
Keyword(s):  
Sexual Selection ◽  
Female Choice ◽  
Egg Production ◽  
Sexual Differences ◽  
The Other ◽  
Sexual Competition ◽  
Sexual Characteristics ◽  
Sexual Selection Theory ◽  
Males And Females ◽  
Selection Of

The idea that males and females often look, sound, smell, and behave differently is uncontroversial. Where those differences came from, however, and what role they play in various species—including humans—is not. ‘Darwin’s other big idea’ outlines Charles Darwin’s sexual selection theory: differential reproduction based on sexual competition, whether between the members of one sex for access to the other, or by selection of particular mating partners. Differences in reproductive parts directly involved in sperm or egg production—primary sexual characteristics—were relatively easy to explain. The other kinds of sexual differences, he proposed, could evolve in one of two ways: male–male competition resulting in weapons, or female choice resulting in ornaments, but this was highly controversial.

Sign in / Sign up

Export Citation Format

Share Document