Chemical Traits in Sexual Selection of the Rove Beetle, Aleochara curtula (Coleoptera: Staphylinidae)

Inter-specific symbiotic links are often reinforced by morphological, physiological, or behavioural trait modification undergone by the associated species. In some cases, such as in physogastric termitophile staphylinids, such modifications do facilitate the social interaction. Here we inspect chemical traits of the physogastric staphylinid Corotoca melantho (Insecta: Coleoptera) and its termite host Constrictotermes cyphergaster (Insecta: Blattodea: Isoptera), aiming to verify whether staphylinids resemble their host. First, we compared CHC profiles of hosts and guests within and among termitaria, to gather evidence on the origin of such profiles in guests. Then, we examined nitrogen and carbon isotopic signatures of these cohabitants to inspect whether chemical disguise is achieved by predation of host workers by staphylinids. Beetles presented CHC more similar to the CHC of their cohabiting termites than to (i) their conspecifics and (ii) termites from another nest, thereby favouring the hypothesis on CHC acquisition by guests. Isotopic signatures revealed that such similarities could not be majorly determined by share nutrition between these cohabitants. In general, our results evidenced that chemical disguise in termitophiles may function as a strategy for social integration in morphological mimics.

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FEMALE CHOICE AND SEXUAL SELECTION OF MALE WING MELANIN PATTERN INPIERIS OCCIDENTALIS(LEPIDOPTERA)

Evolution ◽

10.1111/j.1558-5646.1989.tb02617.x ◽

1989 ◽

Vol 43 (8) ◽

pp. 1672-1682 ◽

Cited By ~ 25

Author(s):

Diane C. Wiernasz

Keyword(s):

Sexual Selection ◽

Female Choice ◽

Male Wing ◽

Selection Of

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

Genetics Research ◽

10.1017/s001667230003192x ◽

1993 ◽

Vol 62 (3) ◽

pp. 213-222 ◽

Cited By ~ 126

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.

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

Canadian Journal of Zoology ◽

10.1139/z97-777 ◽

1997 ◽

Vol 75 (9) ◽

pp. 1532-1535 ◽

Cited By ~ 13

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.

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