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71.
Genetic variability among males is a necessary precondition for the evolution of female choice based on indirect genetic benefits.
In addition to mutations and host–parasite cycles, migration of locally adapted individuals offers an explanation for the
maintenance of genetic variability. In a previous study, conducting a reciprocal transplant experiment on a grasshopper, Chorthippus biguttulus, we found that environmental conditions significantly influenced not only body condition but also an important trait of male
calling song, the amplitude of song. Although not significant, all other analysed physical and courtship song traits and attractiveness
were superior in native than in transferred males. Thus, we concluded that local adaptation has a slight but consistent influence
on a range of traits in our study populations, including male acoustic attractiveness. In our present study, we scanned male
grasshoppers from the same two populations for amplification fragment length polymorphism (AFLP) loci connected with acoustic
attractiveness to conspecific females. We found greater differences in allele frequencies between the two populations, for
some loci, than are expected from a balance between drift and gene flow. These loci are potentially connected with locally
adapted traits. We examined whether these alleles show the proposed genotype environment interaction by having different associations
with attractiveness in the two populations. One locus was significantly related to sexual attractiveness; however, this was
independent of the males’ population affiliation. Future research on the evolution of female choice will benefit from knowledge
of the underlying genetic architecture of male traits under intraspecific sexual selection, and the ‘population genomics’
approach can be a powerful tool for revealing this structure. 相似文献
72.
Recent theoretical and empirical studies have shown that male dominance is often at odds with female mate preference and that
indirect (genetic) benefits of mate choice may not be related to male dominance. We tested whether female preference corresponded
to male dominance and whether mating with dominant males conveyed benefits to offspring fitness in a small freshwater fish,
the African annual killifish Nothobranchius korthausae (Cyprinodontiformes), a species without parental care. The experimental design used controlled for the effect of male age,
possibility of sperm and egg depletion, and accounted for a potential that females express their preference through maternal
effects by manipulation of egg mass during ovulation. By sequentially mating females with males of known dominance, we found
that female N. korthausae showed no mate preference in terms of egg numbers deposited with respect to male dominance or body size and no congruent
mate preference to specific males was detected. However, males sired offspring with consistently higher hatching success and
the effect was repeatable across individual females. Thus, some males provided females with indirect benefits related to additive
genetic quality (“good genes”) and expressed via increased hatching rate, but this benefit was not related to male dominance
status or body size. 相似文献
73.
Gregory E. Blomquist 《Behavioral ecology and sociobiology》2009,63(9):1345-1352
Females of many cercopithecine primates live in stable dominance hierarchies that create long-term asymmetries among sets
of female relatives (matrilines) in access to limiting resources and shelter from psychosocial stress. Rank-related differences
in fitness components are widely documented, but their causes are unclear. Predicted breeding values from an animal model
for female age of first reproduction are used to discriminate between shared additive genetic and shared environmental effects
among the members of matrilines in a population of free-ranging rhesus macaques (Macaca mulatta). While age of first reproduction has a modest heritability (≈0.2), breeding values are distributed in a largely random fashion
among matrilines and contribute little to the observed rank-related differences in average age of first reproduction. These
results support the long-held, but previously unverified, contention that rank-related life history differences in female
cercopithecine primates are the result of environmental rather than genetic differences among them. 相似文献
74.
Barbara A. Caspers Frank C. Schroeder Stephan Franke W. Jürgen Streich Christian C. Voigt 《Behavioral ecology and sociobiology》2009,63(5):741-749
Combining chemical analysis and odour preference tests, we asked whether two closely related sympatric species of sac-winged
bats use odour for species recognition. Males of the two sister species Saccopteryx bilineata and Saccopteryx leptura have pouches containing an odoriferous liquid in their antebrachial wing membrane, which is used in S. bilineata during courtship displays. Although both species occasionally share the same daytime roosts and are morphologically similar,
there is no evidence for interbreeding. We compared the production and composition of the wing sac odorant in male S. leptura and S. bilineata and performed odour preference tests with female S. bilineata. Similar to male S. bilineata, male S. leptura cleansed and refilled their wing sacs with secretions, but they spent more time each day in doing so than male S. bilineata. Chemical analysis by gas chromatography and mass spectrometry revealed that male Saccopteryx carried species-specific scents in their wing sacs. Binary choice tests confirmed that female S. bilineata preferred the wing sac scents of male S. bilineata to those of the sister species, suggesting that the species specificity of male wing sac scents maintain the pre-mating isolation
barrier between these closely related species. 相似文献
75.
Tolerated transfer of food among adults is rare among primates, except in humans. Here, we present data on a consistent pattern
of tolerated intersexual transfer of food (held in hand, foot, or mouth by the owner) among adult orangutans, in two different
natural populations (Pongo abelii and Pongo pygmaeus wurmbii), based on ca. 9,000 h of focal observation per site. Although rare, intersexual food transfers were disproportionately from
males to sexually active females and involved food that was equally available to both sexes. There was no evidence for direct
trading of food for social favors (mating, grooming, or agonistic support) or for sharing under pressure of harassment. However,
females frequently protested with loud screams when males, especially unflanged ones, attempted to take food they possessed,
and also when males responded aggressively to their taking attempt. Since associations ended sooner when the female emitted
noisy calls, a male who did not allow a female to take food from him risked losing the association. These findings support
the hypothesis that by taking food, a sexually active female may test the male's tendency toward violence. Thus, intersexual
food taking in orangutans is based on female leverage, resulting in a species-wide female entitlement to male “generosity”.
The inhibition of food defense required for this kind of transaction may also form the basis for sharing patterns among species
in which nutritional benefits have become important, such as chimpanzees and perhaps human foragers. 相似文献
76.
Vikram K. Iyengar 《Behavioral ecology and sociobiology》2009,63(6):847-855
Determining the factors that affect male mating success is essential to understanding how sexual selection operates, including
explanations of the adaptive value of female preferences and how variation in male traits is maintained in a population. Although
females may appear to choose males based on a single parameter, female mate choice is often a complex series of assessments
of male quality that can only be revealed through manipulation of multiple male traits. In the moth Utetheisa ornatrix (Lepidoptera: Arctiidae), females have been shown to judge males primarily on their production of a courtship pheromone,
hydroxydanaidal, derived from defensive chemicals acquired as larvae. Recent work, however, suggested that other factors,
including prior mating experience by males, may also influence the outcome of precopulatory interactions with females. I ran
mating trials with one female and two males to determine whether there were any differences in male mating success based on
their prior exposure to females, mating experience, and time between matings. Previously mated males were favored over virgins
when both males lacked the pheromone, but courting experience and mating interval did not explain these differences in male
mating success. Furthermore, multiply mated males lacking the pheromone were favored over virgin males that produced the pheromone,
thus reversing the commonly observed trend of female precopulatory bias towards males with higher levels of the pheromone.
These results demonstrate that males with mating experience can secure copulations despite deficiencies in the pheromone,
and I provide possible mechanisms and discuss their implications regarding sexual selection. 相似文献
77.
Carola Borries Kristin Launhardt Cornelia Epplen Jörg T. Epplen Paul Winkler 《Behavioral ecology and sociobiology》1999,46(5):350-356
Hypotheses about the evolution of gregariousness and social organisation in primates are based on ecological explanations
as well as on social factors such as conspecific threat (especially infanticide by males). The social explanation fits well
with the conditions found in strepsirrhine primates and furthermore explains why infanticide in anthropoid primates living
in one-male groups mainly occurs when the resident male (protector) is replaced. However, whether it likewise fits to the
conditions in multimale groups will depend on the role of resident males as infant protectors, which has rarely been examined.
We investigated long-term data of wild Hanuman langurs (Presbytis entellus) inhabiting a forest near the village of Ramnagar (southern Nepal). Twenty-two eye-witnessed attacks on infants by males
were analysed in connection with male residency, paternity (DNA analyses) and sexual behaviour. Adult males played a major
role in infant defence (65%). Only the genetic father or males who had been residents when the infant was conceived were observed
to protect infants. Males who immigrated after a female had conceived may later attack her infant and were never observed
to defend it. lt seems that the males took only copulations with potentially fertile females but not with pregnant females
as clues for paternity. In the light of these results it seems likely that the risk of infanticide is an important determinant
in female-male associations even in anthropoid primate multimale groups.
Received: 22 December 1998 / Received in revised form: 30 April 1999 / Accepted: 1 May 1999 相似文献
78.
J. Soltis R. Thomsen K. Matsubayashi O. Takenaka 《Behavioral ecology and sociobiology》2000,48(3):195-202
Infanticide was observed for the first time in a wild, non-provisioned troop of Japanese macaques on Yakushima Island, Japan.
Eight adult resident males attacked unweaned infants in the pre- and early mating season, and one infanticide was observed
directly. These attacks were not consistent with the social pathology, side effect of male aggression, cannibalism, or the
resource defense hypothesis, but were generally consistent with the sexual-selection hypothesis. First, most male attackers
had risen in dominance rank because several high-ranking males had left the troop. Second, in 78% of cases, male attackers
had not previously been observed to mate with the mothers of victims. Moreover, analysis of subject animal DNA showed that
males did not attack their own offspring. The two mothers who lost their unweaned infants, however, were not subsequently
observed to mate. In fact, almost no mating behavior was observed in the troop. This was most likely due to a poor fruiting
year. Resumption of mating by females who lost their infants may have been inhibited by an intervening environmental variable
which suppressed female reproductive function. These observations contribute to a growing body of evidence which suggests
that sexually selected infanticide can occur in seasonally breeding, multi-male, multi-female primate groups. Female Japanese
macaques are known to mate with multiple males. We found evidence that female mating with multiple males inhibits contact
aggression towards their infants. Adult males attacked infants eight times more often when they had not previously mated with
the mother.
Received: 2 September 1999 / Received in revised form: 27 April 2000 / Accepted: 3 May 2000 相似文献
79.
Sabra L. Klein H. Ray Gamble Randy J. Nelson 《Behavioral ecology and sociobiology》1999,45(5):323-329
Females may choose mates based on secondary sex traits that reflect disease resistance. Accordingly, females should be able
to distinguish between unparasitized and parasitized males, and should prefer to mate with unparasitized individuals. Mate
and odor preferences for uninfected males or males infected with the nematode, Trichinella spiralis, were examined among prairie voles (Microtus ochrogaster) and meadow voles (M. pennsylvanicus). In a 15-min odor preference test, only female meadow voles distinguished between bedding from parasitized and unparasitized
conspecific males, and preferred to spend time with bedding from unparasitized males. Although T. spiralis infection influenced odor preference in female meadow voles, there was no effect of infection status on mate preference among
either species. Testosterone and corticosterone concentrations were not different between parasitized and unparasitized males.
However, among prairie voles, males that spent an increased amount of time with females during the mate preference test had
elevated testosterone concentrations. Taken together, these data suggest that (1) female meadow voles can discriminate between
unparasitized and parasitized males, (2) the effects of infection on steroid hormone concentrations may be masked by the effects
of social interactions, and (3) parasites may represent a selective constraint on partner preference in voles; however, the
life cycle of parasites may influence female preference and should be considered in studies of female preference.
Received: 23 April 1998 / Accepted after revision: 25 October 1998 相似文献
80.
Costs and benefits of brood desertion in female kentish plovers,Charadrius alexandrinus 总被引:3,自引:0,他引:3
Female kentish plovers Charadrius alexandrinus typically desert their broods after the chicks hatch, i.e. 1–4 weeks before the chicks fledge or become independent. In this paper we investigate the costs and benefits of desertion for females. Desertion incurs a cost for females: following desertion chick survival in broods is lower (0.95 +- 0.02 day–1) than before the female deserts (0.98 +- 0.01 day–1). We investigated several possible causes for reduced brood survival by comparing characteristics of broods before and after desertion (controlling for differences in brood age). After desertion males increased the time they spent foraging and they tended to reduce time spent brooding chicks. Increased mortality of chicks may occur in deserted broods because following desertion (1) males spend less time alert in vigilance behaviour than before desertion, (2) they attend the chicks from greater distances, and (3) they show greater distraction display distances (in response to human intruders). Growth or development of chicks, measured by weight gain and tarsus length, was not different before and after desertion. Females gain two potential benefits from desertion: (1) they may remate and produce a second brood within the same breeding season or (2) they may enhance their probability of surviving to breed in a subsequent season. At least 27% of female kentish plovers that deserted remated and renested in the same season in this study. In contrast, we found no evidence that brood desertion increased the survival of females: there was no difference in local survival rate (return rate) for females deserting before or after 6 days brood age. These results clearly demonstrate that female kentish plovers that desert their offspring prior to fledging incur costs, but we suggest that there is a trade-off with the potential benefits gained by remating and making a second breeding attempt in the same season. 相似文献