Mate recognition
Dotaz
Zobrazit nápovědu
Existing research indicates that the shape of various facial regions is linked to perceived attractiveness and perceived formidability. Interestingly, little evidence shows that people directly focus on these specific facial regions during judgments of attractiveness and formidability, and there is little support for the notion that the levels of attractiveness and formidability affect raters' visual attention. We employed eye-tracking to examine visual attention (the number of fixations and dwell time) in 40 women and 37 men, while they assessed 45 male faces in life-sized photographs for attractiveness and formidability. The facial photographs were grouped by varying levels of attractiveness and formidability (low, medium, and high). Our results showed that regardless of the characteristics rated, both men and women paid the most visual attention to the eyes, nose, mouth, and forehead regions. We found statistically discernible variation in visual attention in relation to the rater's sex or target's attractiveness levels for other facial features (the chin, cheeks, or ears), but these differences may not be substantial enough to have practical implications. We suggest that the eyes, the nose, and the mouth regions play a central role in the evolution of face perception as regions most salient to the acquisition of informative cues about others. Further, during both attractiveness and formidability judgments, men looked longer at the stimuli than women did, which may hint at increased difficulty of this task for men, possibly because they compare themselves with the stimuli. Additionally, irrespective of sex, raters looked marginally longer at faces with a medium level of formidability than at those with a high formidability level, which may reflect ambiguity of these stimuli and uncertainty regarding assessment. We found no other significantly relationships between the target's attractiveness and formidability levels and the rater's visual attention to whole faces.
- MeSH
- dospělí MeSH
- krása MeSH
- lidé MeSH
- mínění MeSH
- mladý dospělý MeSH
- obličej * MeSH
- pozornost * fyziologie MeSH
- rozpoznání obličeje fyziologie MeSH
- technologie sledování pohybu očí MeSH
- výběrové chování fyziologie MeSH
- zraková percepce fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Recognition is considered a critical basis for discriminatory behaviours in animals. Theoretically, recognition and discrimination of parasitic chicks are not predicted to evolve in hosts of brood parasitic birds that evict nest-mates. Yet, an earlier study showed that host reed warblers (Acrocephalus scirpaceus) of an evicting parasite, the common cuckoo (Cuculus canorus), can avoid the costs of prolonged care for unrelated young by deserting the cuckoo chick before it fledges. Desertion was not based on specific recognition of the parasite because hosts accept any chick cross-fostered into their nests. Thus, the mechanism of this adaptive host response remains enigmatic. Here, I show experimentally that the cue triggering this 'discrimination without recognition' behaviour is the duration of parental care. Neither the intensity of brood care nor the presence of a single-chick in the nest could explain desertions. Hosts responded similarly to foreign chicks, whether heterospecific or experimental conspecifics. The proposed mechanism of discrimination strikingly differs from those found in other parasite-host systems because hosts do not need an internal recognition template of the parasite's appearance to effectively discriminate. Thus, host defences against parasitic chicks may be based upon mechanisms qualitatively different from those operating against parasitic eggs. I also demonstrate that this discriminatory mechanism is non-costly in terms of recognition errors. Comparative data strongly suggest that parasites cannot counter-evolve any adaptation to mitigate effects of this host defence. These findings have crucial implications for the process and end-result of host-parasite arms races and our understanding of the cognitive basis of discriminatory mechanisms in general.
- MeSH
- analýza rozptylu MeSH
- diskriminace (psychologie) fyziologie MeSH
- druhová specificita MeSH
- financování organizované MeSH
- hnízdění fyziologie MeSH
- lidé MeSH
- mateřské chování fyziologie MeSH
- otcovské chování MeSH
- regresní analýza MeSH
- rozpoznávání (psychologie) fyziologie MeSH
- zpěvní ptáci fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- srovnávací studie MeSH
Squamate reptiles are a highly diversified vertebrate group with extensive variability in social behavior and sexual dimorphism. However, hormonal control of these traits has not previously been investigated in sufficient depth in many squamate lineages. Here, we studied the hormonal control of male sexual behavior, aggressiveness, copulatory organ (hemipenis) size and sex recognition in the gecko Paroedura picta, comparing ovariectomized females, ovariectomized females treated with exogenous dihydrotestosterone (DHT), ovariectomized females treated with exogenous testosterone (T), control females and males. The administration of both T and DHT led to the expression of male-typical sexual behavior in females. However, in contrast to T, increased circulating levels of DHT alone were not enough to initiate the full expression of male-typical offensive aggressive behavior and development of hemipenes in females. Ovariectomized females were as sexually attractive as control females, which does not support the need for the demasculinization of the cues used for sex recognition by ovarian hormones as suggested in other sauropsids. On the other hand, our results point to the masculinization of the sex recognition cues by male gonadal androgens. Previously, we also demonstrated that sexually dimorphic growth is controlled by ovarian hormones in P. picta. Overall, it appears that individual behavioral and morphological sexually-dimorphic traits are controlled by multiple endogenous pathways in this species. Variability in the endogenous control of particular traits could have permitted their disentangling during evolution and the occurrence of (semi)independent changes across squamate phylogeny.
- MeSH
- agrese účinky léků fyziologie MeSH
- androgeny farmakologie MeSH
- dihydrotestosteron farmakologie MeSH
- ještěři metabolismus MeSH
- ovarektomie MeSH
- pohlavní dimorfismus * MeSH
- rozmnožování účinky léků fyziologie MeSH
- sexuální chování zvířat účinky léků fyziologie MeSH
- testosteron farmakologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The nature and hormonal control of cues used for recognition of sex and reproductive status of conspecifics remain largely unstudied in reptiles. It has been proposed that production of a female attractiveness pheromone controlled by female ovarian hormones (and which is suppressed by male gonadal androgens) is necessary to elicit courtship in males. In the case of leopard gecko (Eublepharis macularius), it has been suggested that an individual is recognized as a male and attacked unless it produces female-specific stimuli in its skin and that females are attacked, not courted, while shedding. We tested the reactions of males to control males and control shedding and non-shedding females, castrated males, females treated with exogenous androgens (testosterone and dihydrotestosterone), and prepubertal individuals. The individuals with high androgen levels (i.e., control males and hormone-treated females) were attacked while animals in all the other groups were courted. Our results indicate that in leopard gecko hormonally controlled pheromones advertising female attractiveness are not required and that sex discrimination is based on the presence or absence of cues dependent on masculinization by male gonadal steroids.
- MeSH
- chování zvířat účinky léků MeSH
- dihydrotestosteron krev farmakologie MeSH
- diskriminace (psychologie) účinky léků fyziologie MeSH
- estradiol krev farmakologie MeSH
- ještěři fyziologie MeSH
- námluvy * psychologie MeSH
- pohlavní dimorfismus MeSH
- rozmnožování účinky léků MeSH
- rozpoznávání obrazu účinky léků fyziologie MeSH
- sexuální chování zvířat účinky léků fyziologie MeSH
- sociální chování MeSH
- testosteron krev farmakologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- estradiol aplikace a dávkování fyziologie MeSH
- estrus fyziologie MeSH
- krysa rodu rattus MeSH
- ovarektomie MeSH
- ovarium fyziologie MeSH
- paměť fyziologie MeSH
- sexuální chování zvířat fyziologie MeSH
- sociální chování MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
Flehmen is frequently explained as part of male sexual behaviour, but it can also be associated with overmarking behaviour and thus individual recognition. We tested three explanatory hypotheses of flehmen behaviour: to detect sexual status of a female, to decide whether to overmark an individual, and to improve individual recognition. Additionally, we examined interspecific flehmen differences in the African equids. We observed 130 individuals of all 4 species among 15 groups in 5 zoos. We recorded 4445 eliminations: 142 were accompanied by flehmen and 1648 were inspected by another animal and followed by flehmen (n = 147 cases). As males of all age categories flehmened more often than females we conclude that flehmen serves to detect reproductive status of a female. However, this is not an exclusive explanation as animals of all sex and age categories flehmened when inspecting an elimination. Flehmen was not the predictor of overmarking. Nevertheless, we suggest that foals could use it for individual recognition. We found large interspecific differences with the highest rate of flehmen in African wild ass and least in mountain zebra. Thus, while the main function of flehmen is to detect female reproductive status, inter-individual and inter-species differences also play a role.
- MeSH
- Equidae * MeSH
- koně MeSH
- sexuální chování zvířat * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Previous work on lizards has shown that many sexually dimorphic traits depend on testosterone (T), but the details of this control can vary among species. Here, we tested the role of T on the expression of morphological, physiological, and behavioral traits in Lichtenfelder's gecko (Goniurosaurus lichtenfelderi), from the lizard family Eublepharidae notable for interspecific variation in sexually dimorphic traits and the mode of sex determination. Experiments included three groups of males (intact control, surgically castrated, castrated with T replacement) and two groups of females (intact control, T supplemented). In males, castration caused reductions in 1) the size of hemipenes, 2) offensive aggression, 3) male sexual behavior in a neutral arena, 4) activity of precloacal glands, and 5) loss of male chemical cues for sex recognition. These reductions were not observed in castrated males with T replacement. Interestingly, castrated males performed sexual behavior in their home cages, which shows that the effect of T depends on the environmental context. Notably, tail vibration, previously reported as a courtship behavior in other eublepharids, is displayed by males of G. lichtenfelderi during interactions with conspecifics of both sexes, suggesting an evolutionary shift in the meaning of this signal. In females, T induced growth of hemipenes and male-typical courtship but did not induce precloacal pore activity, aggression, or mounting. In comparison to previous reports on Eublepharis macularius, our results indicate that effects of T do not depend on the mode of sex determination. Further, our results extend our understanding of the complexity of control of male traits and illustrate how lability in the effects of T can be a general mechanism causing evolutionary changes in the components of suites of functionally correlated traits.
- MeSH
- agrese fyziologie MeSH
- androgeny farmakologie fyziologie MeSH
- ještěři fyziologie MeSH
- kastrace MeSH
- námluvy MeSH
- pohlavní dimorfismus MeSH
- procesy určující pohlaví účinky léků fyziologie MeSH
- sexuální chování zvířat účinky léků fyziologie MeSH
- sexuální faktory MeSH
- testosteron farmakologie fyziologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Sex-specific chemical secretions have been widely used as diagnostic characters in chemotaxonomy. The taxonomically confused group of bumblebees has reaped the benefit of this approach through the analyses of cephalic labial gland secretions (CLGS). Most of currently available CLGS descriptions concern species from the West-Palearctic region but few from the New World. Here, the CLGS of four East-Palearctic species Bombus deuteronymus, B. filchnerae, B. humilis, and B. exil (subgenus Thoracobombus) are analysed. Our results show high levels of variability in the major compounds in B. exil. In contrast, we describe a low differentiation in CLGS compounds between B. filchnerae and its phylogenetically closely related taxon B. muscorum. Moreover, the chemical profiles of B. filchnerae and B. muscorum are characterized by low concentrations of the C16 component, which is found in higher concentrations in the other Thoracobombus species. This raises the possibility that courtship behavior as well as environmental constraints could affect the role of the bumblebee males' CLGS.
- MeSH
- analýza hlavních komponent MeSH
- exokrinní žlázy chemie metabolismus MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
- sexuální lákadla analýza chemie MeSH
- včely chemie metabolismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Communication in rhinos is primarily mediated by the vocal and olfactory signals as they have relatively poor eyesight. White rhinos are the most social of all the rhinoceros species, they defecate at common dungheaps and the adult bulls use dung and urine to mark their territory. Chemical communication may therefore be particularly important in the social interactions of white rhinos, and its knowledge could be very helpful in their management and conservation. However, no studies have investigated up until now the olfactory discrimination in any rhinoceros species in the wild. We have experimentally studied the reactions of the wild southern white rhinos (Ceratotherium simum) to the dung of familiar and unfamiliar adult females and adult territorial males. We registered the number of sniffing events, the duration of sniffing and the latency of the vigilance posture from the onset of sniffing. The dung of unfamiliar rhinos was sniffed longer than that of familiar rhinos. The rhinos showed a shorter latency of vigilance posture to the familiar dung of males than that of females. For unfamiliar dung, they displayed a shorter latency of vigilance posture to female than male dung. Our results indicate that the rhinos are able to discriminate the familiarity and sex of conspecifics from the smell of their dung. Olfactory cues could therefore play an important role in the social relationships and spatial organization of the southern white rhinoceros.
- MeSH
- čich * fyziologie MeSH
- diskriminace (psychologie) * fyziologie MeSH
- feces chemie MeSH
- feromony fyziologie MeSH
- komunikace MeSH
- Perissodactyla fyziologie psychologie MeSH
- podněty MeSH
- rozpoznávání (psychologie) * MeSH
- sexuální chování zvířat fyziologie MeSH
- sexuální faktory MeSH
- sexuální lákadla fyziologie MeSH
- sociální chování MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
