Статті в журналах з теми "Intersexual interactions"

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1

Takakura, Koh-Ichi, Takayoshi Nishida, and Keisuke Iwao. "Conflicting intersexual mate choices maintain interspecific sexual interactions." Population Ecology 57, no. 2 (April 2015): 261–71. http://dx.doi.org/10.1007/s10144-015-0492-3.

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2

Akin, Jonathan A. "Intra- and inter-sexual aggression in the ground skink (Scincella lateralis)." Canadian Journal of Zoology 76, no. 1 (January 1, 1998): 87–93. http://dx.doi.org/10.1139/z97-172.

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Differences in reproductive investment between males and females can be a basis for both intra- and inter-sexual conflict. In a series of laboratory experiments, I staged intra- and inter-sexual contests for food between pairs of adult ground skinks (Scincella lateralis). Males were significantly more aggressive than females. Size asymmetry between contestants significantly affected intrasexual behavior between females, as smaller individuals exhibited avoidance behaviors more frequently than larger individuals. Aggression was more prevalent in intersexual contests than in intrasexual contests, and males bit females significantly more often than females bit males. Females captured significantly fewer prey in the presence of a male than in control tests, but showed more avoidance behaviors in intersexual contests than did males. These results suggest that intersexual conflict may be important in social interactions in ground skinks, particularly with respect to spatial distribution.
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3

Soderquist, TR, and L. Ealey. "Social interactions and mating strategies of a solitary carnivorous marsupial, Phascogale tapoatafa, in the wild." Wildlife Research 21, no. 5 (1994): 527. http://dx.doi.org/10.1071/wr9940527.

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The difficulty of observing the behaviour of cryptic, nocturnal carnivorous marsupials (Dasyuridae) in the wild has created a reliance on laboratory studies for the analysis of social interactions. Behavioural data on wild Phascogale tapoatafa suggest that previous interpretations may be biased by laboratory confinement. The play of juvenile P. tapoatafa entailed brief, non-contact chases, which apparently provide social practice prior to the solitary, post-dispersal life of adults. Interactions between wild adults very rarely included physical contact. Most encounters (63%) comprised chases, of which only female-female interactions commonly displaced the chased animal more than 3 m. Wild females readily deterred males from approaching closely by vocal threatening, even during the peak of the breeding season, so that forced copulation (as reported in captive dasyurids) was unlikely. Scent-presentation experiments suggested that sternal marking by males was intersexual communication, and may serve, along with intersexual chases, to familiarise females with future mates.
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4

Edwards, J. C., and C. J. Barnard. "The effects of Trichinella infection on intersexual interactions between mice." Animal Behaviour 35, no. 2 (April 1987): 533–40. http://dx.doi.org/10.1016/s0003-3472(87)80278-6.

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5

Zammit, John, and Michael P. Schwarz. "Intersexual sibling interactions and male benevolence in a fig wasp." Animal Behaviour 60, no. 5 (November 2000): 695–701. http://dx.doi.org/10.1006/anbe.2000.1522.

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6

Thaker, Maria, Caitlin Gabor, Joe Fries, and Kristen Epp. "Cohabitation patterns of the San Marcos salamander (Eurycea nana)." Amphibia-Reptilia 31, no. 4 (2010): 503–8. http://dx.doi.org/10.1163/017353710x524697.

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AbstractSocial interactions of conspecifics are a function of complex relationships involving resource defense, antipredatory tactics, and mate acquisition. Consequently, individuals often associate non-randomly with conspecifics in their habitats, with spatial distributions of adults ranging from territorial spacing to aggregations. Site tenacity and cohabitation patterns have been well studied in many species of terrestrial salamander; however, less is understood about these behaviors in aquatic species. We examined the cohabitation patterns of intrasexual and intersexual pairs of the federally threatened, paedomorphic San Marcos salamander (Eurycea nana) under artificial shelters in a laboratory setting over a 20-day period. We found that intrasexual female pairs and intersexual pairs were found cohabiting more often than intrasexual male pairs. We also assessed site tenacity by examining shelter affinity and found that both males and females inhabited one of the two shelters more often than expected from random habitation, regardless of whether they were in intersexual or intrasexual pairings. Our results indicate that although both sexes of Eurycea nana exhibit site affinity, the sex of individuals is an important determinant of cohabitation patterns.
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7

Sánchez-Hernández, Paula, M. Mercedes Suárez-Rancel, and Miguel Molina-Borja. "Intersexual behaviour and effect of male and female intruders in the Tenerife skink (Chalcides viridanus). Is there any mate guarding?" Behaviour 158, no. 10 (June 30, 2021): 901–19. http://dx.doi.org/10.1163/1568539x-bja10100.

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Abstract Individuals avoid potential competitors accessing mates during reproductive periods staying close to the mate and chasing same-sex intruders. We studied intersexual relationships and the effect of intruders of each sex in male-female pairs of Chalcides viridanus. We analysed: (1) behaviour patterns of each pair member and the time they spent together during three successive days in March, April and May; and (2) interactions of intruder-resident of the same sex, during each of the three months. Sexual and monthly differences appeared in intersexual behaviour as the breeding season progressed. In each month, time together was significantly larger on the third trial day than in the two previous days but did not significantly change between months. Sexes did not significantly differ in intruder-resident behaviours, but male aggressive interactions were significantly larger in May. Intruder females performed higher frequencies of non-agonistic behaviours than residents. We discuss all these results considering the predictions of mate guarding hypothesis.
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8

Yun, Li, Patrick J. Chen, Amardeep Singh, Aneil F. Agrawal, and Howard D. Rundle. "The physical environment mediates male harm and its effect on selection in females." Proceedings of the Royal Society B: Biological Sciences 284, no. 1858 (July 5, 2017): 20170424. http://dx.doi.org/10.1098/rspb.2017.0424.

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Recent experiments indicate that male preferential harassment of high-quality females reduces the variance in female fitness, thereby weakening natural selection through females and hampering adaptation and purging. We propose that this phenomenon, which results from a combination of male choice and male-induced harm, should be mediated by the physical environment in which intersexual interactions occur. Using Drosophila melanogaster , we examined intersexual interactions in small and simple (standard fly vials) versus slightly more realistic (small cages with spatial structure) environments. We show that in these more realistic environments, sexual interactions are less frequent, are no longer biased towards high-quality females, and that overall male harm is reduced. Next, we examine the selective advantage of high- over low-quality females while manipulating the opportunity for male choice. Male choice weakens the viability advantage of high-quality females in the simple environment, consistent with previous work, but strengthens selection on females in the more realistic environment. Laboratory studies in simple environments have strongly shaped our understanding of sexual conflict but may provide biased insight. Our results suggest that the physical environment plays a key role in the evolutionary consequences of sexual interactions and ultimately the alignment of natural and sexual selection.
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9

McLean, Morgan J., Phillip J. Bishop, Jean-Marc Hero, and Shinichi Nakagawa. "Assessing the information content of calls of Litoria chloris: quality signalling versus individual recognition." Australian Journal of Zoology 60, no. 2 (2012): 120. http://dx.doi.org/10.1071/zo12014.

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In many species, male animals produce costly signals to attract females. Intersexual indicator theories propose that these signals are indicative of male quality, whereas individual recognition models are based on the idea that male signals are used primarily to allow for individual discrimination. These two types of models make differing predictions about the nature of male signals. In particular, these models’ predictions differ in the information about a male’s quality that will be included in his signal, the frequency distributions of male signals in a population, and the ways in which the different traits that make up a signal will covary. Calls from the Australian frog Litoria chloris were tested for consistency with the predictions of intersexual indicator models and individual recognition models. The calls were found to contain minimal information on male quality, and the covariance between different signal traits was consistent with the individual recognition models. However, the frequency distributions of male signal traits agreed with intersexual indicator models. In addition, this study found evidence that the information content of calls may instead mediate intrasexual interactions, although more research is required to determine if this is the case.
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10

Popović, Miloš, Ana Golubović, and Piotr Nowicki. "Intersexual Differences in Behaviour and Resource Use of Specialist Phengaris teleius Butterflies." Insects 13, no. 3 (March 6, 2022): 262. http://dx.doi.org/10.3390/insects13030262.

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Although the behaviour of the Large Blue butterflies of the genus Phengaris (= Maculinea) is relatively well studied, most empirical data come from investigations of their dispersal and oviposition. Here, we assessed overall intersexual differences in resource use by tracking Phengaris teleius (Bergsträsser, 1779) individuals and recording the duration of their behaviours. Females were characterised by frequent, short flights, and devoted more time to resting and oviposition. Males engaged in numerous, but usually short interactions, and spent most of the time in flight exploring their surroundings for receptive females. Their average flight time was significantly longer compared to females. Average feeding time did not differ between the sexes but was shorter when butterflies were feeding on Sanguisorba officinalis L. Intraspecific interactions within P. teleius were three times longer than those with other insect species, and interactions between sexes were particularly long lasting. Significantly shorter interspecific interactions imply that butterflies can easily recognise conspecifics and differentiate between sexes, which offers obvious fitness benefits. Both sexes, but especially females, showed strong association with their larval host plant, and less so with other flowers of similar colour and shape. Females predominantly used their host plant for feeding, which possibly indicates neuro-sensory constraints towards this resource.
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11

Hamilton, David G., Menna E. Jones, Elissa Z. Cameron, Hamish McCallum, Andrew Storfer, Paul A. Hohenlohe, and Rodrigo K. Hamede. "Rate of intersexual interactions affects injury likelihood in Tasmanian devil contact networks." Behavioral Ecology 30, no. 4 (April 25, 2019): 1087–95. http://dx.doi.org/10.1093/beheco/arz054.

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Abstract Identifying the types of contacts that result in disease transmission is important for accurately modeling and predicting transmission dynamics and disease spread in wild populations. We investigated contacts within a population of adult Tasmanian devils (Sarcophilus harrisii) over a 6-month period and tested whether individual-level contact patterns were correlated with accumulation of bite wounds. Bite wounds are important in the spread of devil facial tumor disease, a clonal cancer cell line transmitted through direct inoculation of tumor cells when susceptible and infected individuals bite each other. We used multimodel inference and network autocorrelation models to investigate the effects of individual-level contact patterns, identities of interacting partners, and position within the social network on the propensity to be involved in bite-inducing contacts. We found that males were more likely to receive potentially disease-transmitting bite wounds than females, particularly during the mating season when males spend extended periods mate-guarding females. The number of bite wounds individuals received during the mating season was unrelated to any of the network metrics examined. Our approach illustrates the necessity for understanding which contact types spread disease in different systems to assist the management of this and other infectious wildlife diseases.
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12

Smith, Joshua N., Anne W. Goldizen, Rebecca A. Dunlop, and Michael J. Noad. "Songs of male humpback whales, Megaptera novaeangliae, are involved in intersexual interactions." Animal Behaviour 76, no. 2 (August 2008): 467–77. http://dx.doi.org/10.1016/j.anbehav.2008.02.013.

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13

Zwickel, Fred C., and Allen Allison. "Inter- and intra-sexual interactions in a New Guinea skink, Emoia physicae." Canadian Journal of Zoology 64, no. 3 (March 1, 1986): 752–55. http://dx.doi.org/10.1139/z86-111.

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Three experiments were conducted in outdoor arenas with a small, New Guinea skink, Emoia physicae, to examine inter- and intra-sexual interactions. There were statistically significant differences in behaviour between adult males and adult females and in interactions within the sexes. Within sexes, larger lizards dominated smaller ones. Females dominated males, even though females are smaller. Intrasexual encounters were more likely to be agonistic than were intersexual encounters. Intrasexual encounters were more likely to be overtly agonistic among males than among females, but females often avoided one another. Both sexes of E. physicae exhibit behaviors that could function in a territorial context.
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14

Otronen, Merja. "Intra-and intersexual interactions at breeding burrows in the horned beetle, Coprophanaeus ensifer." Animal Behaviour 36, no. 3 (June 1988): 741–48. http://dx.doi.org/10.1016/s0003-3472(88)80157-x.

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15

Blackburn, Gwylim S., and Wayne P. Maddison. "Insights to the mating strategies of Habronattus americanus jumping spiders from natural behaviour and staged interactions in the wild." Behaviour 152, no. 9 (2015): 1169–86. http://dx.doi.org/10.1163/1568539x-00003273.

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We documented natural behaviour and staged intersexual interactions ofHabronattusamericanusjumping spiders in the wild in order to clarify three aspects of their mating strategies: (1) Do males invest more than females in locomotory mate search? (2) Do females exert strong mate choice? (3) Do direct contests occur among males? Males apparently invested heavily in mate search, travelling more than females yet eating nothing. Conversely, females frequently hunted and spent 10% of their time feeding. Females encountered one male per hour, likely affording them a high degree of choice among prospective mates. Accordingly, they promoted the termination of each interaction and ultimately rejected nearly all courting males. Male–male interactions were brief and did not feature direct antagonism. Our findings suggest that mate competition inH. americanusis characterized by male scramble competition for dispersed females, and that female mate choice may exert strong selection on male sexual display traits.
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16

Russell, Avery L., David W. Kikuchi, Noah W. Giebink, and Daniel R. Papaj. "Sensory bias and signal detection trade-offs maintain intersexual floral mimicry." Philosophical Transactions of the Royal Society B: Biological Sciences 375, no. 1802 (May 18, 2020): 20190469. http://dx.doi.org/10.1098/rstb.2019.0469.

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Mimicry is common in interspecies interactions, yet conditions maintaining Batesian mimicry have been primarily tested in predator–prey interactions. In pollination mutualisms, floral mimetic signals thought to dupe animals into pollinating unrewarding flowers are widespread (greater than 32 plant families). Yet whether animals learn to both correctly identify floral models and reject floral mimics and whether these responses are frequency-dependent is not well understood. We tested how learning affected the effectiveness and frequency-dependence of imperfect Batesian mimicry among flowers using the generalist bumblebee, Bombus impatiens , visiting Begonia odorata , a plant species exhibiting intersexual floral mimicry. Unrewarding female flowers are mimics of pollen-rewarding male flowers (models), though mimicry to the human eye is imperfect. Flower-naive bees exhibited a perceptual bias for mimics over models, but rapidly learned to avoid mimics. Surprisingly, altering the frequency of models and mimics only marginally shaped responses by naive bees and by bees experienced with the distribution and frequency of models and mimics. Our results provide evidence both of exploitation by the plant of signal detection trade-offs in bees and of resistance by the bees, via learning, to this exploitation. Critically, we provide experimental evidence that imperfect Batesian mimicry can be adaptive and, in contrast with expectations of signal detection theory, functions largely independently of the model and mimic frequency. This article is part of the theme issue ‘Signal detection theory in recognition systems: from evolving models to experimental tests’.
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17

Bedulina, Daria, Michael F. Meyer, Anton Gurkov, Ekaterina Kondratjeva, Boris Baduev, Roman Gusdorf, and Maxim A. Timofeyev. "Intersexual differences of heat shock response between two amphipods (Eulimnogammarus verrucosusandEulimnogammarus cyaneus) in Lake Baikal." PeerJ 5 (February 21, 2017): e2864. http://dx.doi.org/10.7717/peerj.2864.

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Acute temperature fluctuations are common in surface waters, and aquatic organisms may manifest physiological responses to punctuated temperature spikes long before behavioral responses. Ectotherms, especially cryophilic stenotherms such as those endemic to Lake Baikal (Siberia), may demonstrate specialized physiological responses to acute temperature increases because their proteomes have evolved to function most efficiently at lower temperatures (e.g., <10 °C). Therefore, our study questioned the nature and degree of variation in physiological response to acute thermal stress in two congenerous, endemic Baikal amphipod species,Eulimnogammarus verrucosusandEulimnogammarus cyaneus. We hypothesized that because interspecific and intersexual thermosensitivity varies significantly among ectotherms, there would be divergent intersexual and interspecific strategies to withstand acute thermal stress, manifested in different protein compositions and concentrations. We exposed individuals to the species’ respective LT50 for one hour followed by a three-hour recovery period. We then performed 1D-PAGE, Western blotting, 2D-PAGE, and Mass Spectrometry techniques and assessed relative intersexual and interspecific changes in proteomic composition and heat shock protein 70 level. Our results demonstrate that females tend to be more sensitive to an acute thermal stimulus than males, most likely because females allocate significant energy to reproduction and less to heat shock response, evidenced by females’ significantly lower LT50time. Lower level of Hsp70 was found in females of the thermosensitiveE. verrucosuscompared to males of this species. No intersexual differences were found in Hsp70 level in thermotolerantE. cyaneus. Higher levels of hemocyanin subunits and arginine kinase were found inE. cyaneusfemales after heat shock and recovery compared to males, which was not found forE. verrucosus, suggesting interspecific mechanisms forE. cyaneus’s higher thermotolerance. These differing responses between species and sexes of Baikal amphipods may reflect more general strategies for maintaining homeostatic conditions during acute thermal stress. As mean surface water temperatures increase worldwide, the net efficiency and efficacy of these strategies could give rise to long term changes in physiology, behavior, and interactions with other species, potentially precipitating population and community level alterations.
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18

Cholewiak, Danielle M., Salvatore Cerchio, Jeff K. Jacobsen, Jorge Urbán-R., and Christopher W. Clark. "Songbird dynamics under the sea: acoustic interactions between humpback whales suggest song mediates male interactions." Royal Society Open Science 5, no. 2 (February 2018): 171298. http://dx.doi.org/10.1098/rsos.171298.

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The function of song has been well studied in numerous taxa and plays a role in mediating both intersexual and intrasexual interactions. Humpback whales are among few mammals who sing, but the role of sexual selection on song in this species is poorly understood. While one predominant hypothesis is that song mediates male–male interactions, the mechanism by which this may occur has never been explored. We applied metrics typically used to assess songbird interactions to examine song sequences and movement patterns of humpback whale singers. We found that males altered their song presentation in the presence of other singers; focal males increased the rate at which they switched between phrase types ( p = 0.005), and tended to increase the overall evenness of their song presentation ( p = 0.06) after a second male began singing. Two-singer dyads overlapped their song sequences significantly more than expected by chance. Spatial analyses revealed that change in distance between singers was related to whether both males kept singing ( p = 0.012), with close approaches leading to song cessation. Overall, acoustic interactions resemble known mechanisms of mediating intrasexual interactions in songbirds. Future work should focus on more precisely resolving how changes in song presentation may be used in competition between singing males.
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19

Koga, Tsunenori, Hoi-Sen Yong, and Minoru Murai. "MALE-MALE COMPETITION AND INTERSEXUAL INTERACTIONS IN UNDERGROUND MATING OF THE FIDDLER CRAB UCA PARADUSSUMIERI." Behaviour 136, no. 5 (1999): 651–67. http://dx.doi.org/10.1163/156853999501504.

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AbstractWe investigated inter-male competition for female mates and intersexual interactions in underground mating (UM) of the fiddler crab Uca paradussumieri . Males search for and then enter the burrows of females that are ready to ovulate ('pre-ovigerous'). In order to ensure their paternity, these males guard the female until she ovulates the following day. Thereafter the male leaves. Intruding male conspecifics attempt to reach the female. Guarding males either fight with them (N = 27), or use the flat-claw defence (N = 96) in which the male stands in the burrow shaft and blocks the entrance with his enlarged claw. The flat-claw was a very successful defence tactic (93% success), even when the intruder was larger than the guarding male. Pre-ovigerous females accepted the first male to enter her burrow, suggesting that female mate choice does not occur. Though males that succeeded to enter the burrow of pre-ovigerous female were larger than males that failed to do so, males that succeeded UM were not larger than males that failed UM. Males that succeeded UM by a take-over were not larger than either the males that were defeated or the males that succeeded in UM after their first entering. Early localization of pre-ovigerous females was important in male mating success, as was a male's ability to defend the female before she ovulated. However, some females that were not pre-ovigerous were guarded forcibly for 2 days by males that had failed to pair with a pre-ovigerous female that day. Prolonged guarding was less successful for males than guarding for one day, probably because the males had to fight with more intruders. In addition, prolonged guarding may not be adaptive for females because they lose feeding time and mate with males that lack competitive abilities.
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20

Willink, Beatriz, and Erik I. Svensson. "Intra- and intersexual differences in parasite resistance and female fitness tolerance in a polymorphic insect." Proceedings of the Royal Society B: Biological Sciences 284, no. 1847 (January 25, 2017): 20162407. http://dx.doi.org/10.1098/rspb.2016.2407.

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To understand host–parasite interactions, it is necessary to quantify variation and covariation in defence traits. We quantified parasite resistance and fitness tolerance of a polymorphic damselfly ( Ischnura elegans ), an insect with three discrete female colour morphs but with monomorphic males. We quantified sex and morph differences in parasite resistance (prevalence and intensity of water mite infections) and morph-specific fitness tolerance in the females in natural populations for over a decade. There was no evidence for higher parasite susceptibility in males as a cost of sexual selection, whereas differences in defence mechanisms between female morphs are consistent with correlational selection operating on combinations of parasite resistance and tolerance. We suggest that tolerance differences between female morphs interact with frequency-dependent sexual conflict, which maintains the polymorphism locally. Host–parasite interactions can therefore shape intra- and intersexual phenotypic divergence and interfere with sexual selection and sexual conflict.
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21

Morrison, Michael L., and Kimberly A. With. "Interseasonal and Intersexual Resource Partitioning in Hairy and White-Headed Woodpeckers." Auk 104, no. 2 (April 1, 1987): 225–33. http://dx.doi.org/10.1093/auk/104.2.225.

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Abstract Foraging behavior in the closely related Hairy (Picoides villosus) and White-headed (P. albolarvatus) woodpeckers was examined in an area of sympatry to evaluate interseasonal and intersexual resource use. Similar foraging heights were observed for each species-sex sample during summer, but significant differences were evident during winter. Male and female White-heads maintained similar relative foraging heights between seasons, whereas male and female Hairies foraged relatively higher during winter. Use of tree species differed significantly for each class between seasons, except for male Hairies. Differences in foraging substrates and tree health also were noted interseasonally. All foraged at similar times of day during summer, but negative relationships occurred between times of foraging during winter; foraging times were significantly different between male Hairies and White-heads. A general trend toward decreased overlap in foraging behaviors during winter was a reflection of concentration of foraging activities on live incense cedar (Calocedrus decurrens), especially by female White-heads. This change apparently was due to the presence of an abundant and accessible prey (incense cedar scale, Xylococculus macrocarpae) on cedar. Behavioral shifts in foraging activities may be related to the differential ability to extract prey as a function of bill morphology; such an idea can be extended to intersexual as well as interseasonal considerations. Thus, segregation of foraging activities in these two woodpecker species may be attributed to morphological differences and habitat complexity rather than to competitive interactions dictated by resource limititions.
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22

Golestaninasab, M., M. Malek, B. Jalali, and I. Mobedi. "Variation in the sex ratio of Rhabdochona fortunatowi (Spirurida: Rhabdochonidae) in Capoeta capoeta gracilis (Cypriniformes: Cyprinidae), relative to levels of infection, host size and temperature." Journal of Helminthology 86, no. 1 (February 9, 2011): 41–45. http://dx.doi.org/10.1017/s0022149x11000010.

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AbstractIn the present study, 81 specimens of Capoeta capoeta gracilis (Keyserling, 1861) were collected from the Shiroud River, the Caspian drainage basin, Iran in June and October 2007. The fish were examined for infection with the nematode Rhabdochona fortunatowi (Dinnik, 1933). Nematodes were counted and sexed, then the sex ratio and intestinal site preference of the R. fortunatowi individuals and the intersexual interactions of the parasites were investigated. Significant differences were observed in the prevalence and intensity of infection in relation to host size and sampling season, but not host sex. Parasite burden (mean intensity) was higher in October than in June and the results revealed a decrease in female-to-male sex ratio (FMR) in the fish in October compared to the ones in June. In other words, as the mean intensity of infection of R. fortunatowi increases, the proportion of male worms increases, too. The female-biased sex ratio in June was replaced by a male-biased one in October. Nematode distribution rose to a significant peak in the mid-region of the fish intestine relative to the anterior and posterior parts. Some changes in the distribution of male and female worms in different parts of the host intestine were also observed during June and October. Density-dependent selection and intersexual competition seem to be the main factors driving such a shift in the sex ratio and its variation in different parts of the host intestine.
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23

Costello, Robin A., Phoebe A. Cook, Edmund D. Brodie, and Vincent A. Formica. "Multilevel selection on social network traits differs between sexes in experimental populations of forked fungus beetles." Evolution 77, no. 1 (December 8, 2022): 289–303. http://dx.doi.org/10.1093/evolut/qpac012.

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Abstract Both individual and group behavior can influence individual fitness, but multilevel selection is rarely quantified on social behaviors. Social networks provide a unique opportunity to study multilevel selection on social behaviors, as they describe complex social traits and patterns of interaction at both the individual and group levels. In this study, we used contextual analysis to measure the consequences of both individual network position and group network structure on individual fitness in experimental populations of forked fungus beetles (Bolitotherus cornutus) with two different resource distributions. We found that males with high individual connectivity (strength) and centrality (betweenness) had higher mating success. However, group network structure did not influence their mating success. Conversely, we found that individual network position had no effect on female reproductive success but that females in populations with many social interactions experienced lower reproductive success. The strength of individual-level selection in males and group-level selection in females intensified when resources were clumped together, showing that habitat structure influences multilevel selection. Individual and emergent group social behavior both influence variation in components of individual fitness, but impact the male mating success and female reproductive success differently, setting up intersexual conflicts over patterns of social interactions at multiple levels.
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24

Wortham-Neal, Jennifer. "Intraspecific agonistic interactions of squilla empusa (crustacea: stomatopoda)." Behaviour 139, no. 4 (2002): 463–86. http://dx.doi.org/10.1163/15685390260135961.

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AbstractMantis shrimp are benthic, predatory marine crustaceans that have complex agonistic interactions. These crustaceans are divided into two functional groups based on the morphology and use of their raptorial appendage: smashers and spearers. Most research on the agonistic behaviours of mantis shrimp has focused on smasher species and on contests between asymmetrical and same-sex individuals. No studies have investigated the intersexual and intrasexual interactions of size-matched spearer individuals. I conducted a laboratory experiment using Squilla empusa, a spearer that lives in the Gulf of Mexico, to determine if agonistic differences exist between males and females. The results suggest that (1) although threat displays are rare in both males and females, male aggressive interactions involving physical contact are common, (2) males engage in more aggressive behaviours and interactions than do females, (3) females are less aggressive toward both males and females than males are toward males and females; interactions involving females are usually passive, non-striking, whereas interactions involving males can result equally in a strike or passive behaviour, (4) males are more aggressive than females, and (5) an increase in the number of treatment individuals resulted in an increase in the number of interactions. The behaviours of Squilla empusa are compared with literature reports concerning other species of mantis shrimp. The differences in habitat, feeding method, vision, and burrow type may explain the differences between smashers and spearer agonistic behaviours.
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25

Stern, Julia, Tanja M. Gerlach, and Lars Penke. "Probing Ovulatory-Cycle Shifts in Women’s Preferences for Men’s Behaviors." Psychological Science 31, no. 4 (March 4, 2020): 424–36. http://dx.doi.org/10.1177/0956797619882022.

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The existence of ovulatory-cycle shifts in women’s mate preferences has been a point of controversy. There is evidence that naturally cycling women in their fertile phase, compared with their luteal phase, evaluate specific behavioral cues in men as more attractive for sexual relationships. However, recent research has cast doubt on these findings. We addressed this debate in a large, preregistered, within-participants study using salivary-hormone measures and luteinizing-hormone tests. One hundred fifty-seven female participants rated the sexual and long-term attractiveness of 70 men in dyadic intersexual interactions in natural videos. Multilevel comparisons across two ovulatory cycles indicated that women’s mate preferences for men’s behaviors did not shift across the cycle for either competitive or courtship behavior. Within-women hormone levels and relationship status did not affect these results. Hormonal mechanisms and implications for estrus theories are discussed.
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26

Singh, Yeshwant, Hari Narayan Kushwaha, Anamika Misra, Mahendra Kumar Hidau, and Shio Kumar Singh. "Time Course of the Changes in Novel Trioxane Antimalarial 99/411 Pharmacokinetics upon Antiepileptic Drugs Co-Administration in SD Rats." Malaria Research and Treatment 2014 (October 14, 2014): 1–7. http://dx.doi.org/10.1155/2014/756965.

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Objective. The study aimed to evaluate the influences of coadministration of antiepileptic drugs (AEDs) on an antimalarial candidate 99/411 pharmacokinetic (PK) profile. Method. For this, single oral dose PK drug interaction studies were conducted between 99/411 and FDA approved AEDs, namely, Phenytoin (PHT), Carbamazepine (CBZ), and Gabapentin (GB) in both male and female SD rats, to assess the coadministered and intersexual influences on 99/411 PK profile. Results. Studies revealed that there were no significant alterations in the PK profile of 99/411 upon PHT and CBZ coadministration in both male and female rats, while systemic exposure of 99/411 was significantly increased by about 80% in female rats upon GB coadministration. In terms of AUC, there was an increase from 2471 ± 586 to 4560 ± 1396 ng·h/mL. Overall, it was concluded that simultaneous administration of AEDs with 99/411 excludes the requirements for dose adjustment, additional therapeutic monitoring, contraindication to concomitant use, and/or other measures to mitigate risk, except for GB coadministration in females. These findings are further helpful to predict such interactions in humans, when potentially applied through proper allometric scaling to extrapolate the data.
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27

Chen, Wen-Hsuan, Anthony Bain, Sheng-Yang Wang, Yi-Chiao Ho, and Hsy-Yu Tzeng. "Mediation of a Mutualistic Conflict for Pollination via Fig Phenology and Odor Recognition between Ficus and Fig Wasp." Plants 11, no. 19 (October 3, 2022): 2603. http://dx.doi.org/10.3390/plants11192603.

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The vegetative and reproductive growth of plants provide the basic tempo for an ecosystem, and when species are interdependent, phenology becomes crucial to regulating the quantity and quality of the interactions. In plant–insect interactions, the plants signal the beginning of their reproductive period with visual and chemical cues; however, in the case of Ficus mutualism, the cues are strictly chemical. The volatile organic compounds emitted by a fig species are a unique, specific blend that provides a signal to mutualistic wasps that the figs are receptive for pollination. In this study, we studied both the phenological pattern of Ficus septica in Central Taiwan and its emissions of volatile compounds at receptivity. This dioecious fig species displays a pattern of continuous vegetative and reproductive production all through the year with a decrease in winter. In parallel, the odor blends emitted by male and female trees are similar but with seasonal variations; these are minimal during winter and increase with the size of the wasp population during the favorable season. In addition, the pollinating females cannot distinguish between the male and female summer odor blends. The link between odor similarity, pollinators and intersexual conflict is discussed.
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28

Long, Kirstin I. "Spatio-temporal interactions among male and female long-nosed potoroos, Potorous tridactylus (Marsupialia : Macropodoidea): mating system implications." Australian Journal of Zoology 49, no. 1 (2001): 17. http://dx.doi.org/10.1071/zo00077.

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Анотація:
This study investigated the mating system of the long-nosed potoroo, Potorous tridactylus, by examining temporal associations between individuals, and patterns of home-range overlap. Six adult females and five adult males were radio-tracked at intervals throughout the 24-h day from December 1996 to March 1997 in south-western Victoria. Home ranges of individuals overlapped with multiple members of each sex; however, intrasexual overlap was significantly lower than intersexual overlap. When data from consecutive radio-tracking sessions were examined, the locations of resting or ‘squat’ areas were identified. These were almost entirely intrasexually exclusive. Male home ranges overlapped the squat areas of one or more females; however, males did not regularly associate with every female whose squat area they overlapped. In three of four cases, pairs of a male and a female associated regularly and spent a greater proportion of time in close proximity to each other than would be expected if they were moving at random. In the past it has been assumed that males monitor the sexual status of females while they rest in squats. If this is the case, the mating system of long-nosed potoroos will be largely dictated by the number of female squat areas that a male is able to regularly monitor within his home range.
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29

Rosengrave, Patrice, Robert Montgomerie, and Neil Gemmell. "Cryptic female choice enhances fertilization success and embryo survival in chinook salmon." Proceedings of the Royal Society B: Biological Sciences 283, no. 1827 (March 30, 2016): 20160001. http://dx.doi.org/10.1098/rspb.2016.0001.

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In this study, we investigated two potentially important intersexual postcopulatory gametic interactions in a population of chinook salmon ( Oncorhynchus tshawytscha ): (i) the effect of female ovarian fluid (OF) on the behaviour of spermatozoa during fertilization and (ii) the effects of multilocus heterozygosity (MLH) (as an index of male quality) and female–male genetic relatedness on sperm behaviour and male fertilization success when there is sperm competition in the presence of that OF. To do this, we conducted a series of in vitro competitive fertilization experiments and found that, when ejaculates from two males are competing for access to a single female's unfertilized eggs, fertilization success was significantly biased towards the male whose sperm swam fastest in the female's OF. Embryo survival—a measure of fitness—was also positively correlated with both sperm swimming speed in OF and male MLH, providing novel evidence that cryptic female choice is adaptive for the female, enhancing the early survival of her offspring and potentially influencing her fitness.
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30

Liu, Miao, Yuting Wang, Xiucheng Liu, Helena Korpelainen, and Chunyang Li. "Intra- and intersexual interactions shape microbial community dynamics in the rhizosphere of Populus cathayana females and males exposed to excess Zn." Journal of Hazardous Materials 402 (January 2021): 123783. http://dx.doi.org/10.1016/j.jhazmat.2020.123783.

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31

Larson, Douglas L., Jacob G. Kimmel, Joseph J. Riedy, Jonathan Hegna, Edward A. Baker, and Kim T. Scribner. "Male lake sturgeon (Acipenser fulvescens) migratory and spawning behaviors are associated with sperm quality and reproductive success." Canadian Journal of Fisheries and Aquatic Sciences 77, no. 12 (December 2020): 1943–59. http://dx.doi.org/10.1139/cjfas-2020-0124.

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Intra-annual reproductive investments may not be predictive of male reproductive success because of the effects of intra- and intersexual interactions on sperm depletion. For long-lived iteroparous fish species such as lake sturgeon (Acipenser fulvescens), reproductive effort may affect lifetime reproductive success. Radio frequency identification antennas were placed at the mouth of the Upper Black River, Michigan, and downstream of spawning locations to quantify male migratory and mating behaviors, including upstream migration time (UT), river residence time (RT), number of intra-annual spawning migrations (IM), interannual spawning interval, and operational sex ratio during 2017–2018. Computer assisted sperm analysis was used to quantify sperm quality. RT had a strong negative influence on sperm concentration and with measures of sperm quality. RT and the number of females encountered were positively associated with male reproductive success (number of offspring sired) across years. RT, IM, and UT were negatively associated with sperm quality, indicating sperm depletion is a reliable measure of sexual activity. Results demonstrate trade-offs between benefits and costs associated with current reproductive effort on future reproduction.
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32

Fisher, Heidi S., and Gil G. Rosenthal. "Male swordtails court with an audience in mind." Biology Letters 3, no. 1 (October 31, 2006): 5–7. http://dx.doi.org/10.1098/rsbl.2006.0556.

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Females are usually considered to be the target of male courtship behaviour. In nature, however, social interactions rarely occur without other observers; thus, it is conceivable that some male courtship behaviours are directed not towards females, but rather towards male rivals. The northern swordtail, Xiphophorus birchmanni , is a freshwater fish found in high densities in natural streams. Males court by swimming close to and in parallel with the female, raising their large sail-like dorsal fin, and quivering briefly. Here, we show that females prefer males that display small dorsal fins to those with large ones, and that males are less aggressive to other males with large dorsal fins. Male swordtails also raise their dorsal fins more frequently when courting in the presence of other males. These results suggest that, despite female avoidance of large dorsal fins, males that raise their fin during courtship benefit by intimidating potential competitors; the intended receivers of this signal are thus males, not females. Intrasexual selection can therefore offset the forces of intersexual selection, even in a courtship display.
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33

Willemart, Rodrigo H., Jean-Pierre Farine, Alfredo V. Peretti, and Pedro Gnaspini. "Behavioral roles of the sexually dimorphic structures in the male harvestman, Phalangium opilio (Opiliones, Phalangiidae)." Canadian Journal of Zoology 84, no. 12 (December 2006): 1763–74. http://dx.doi.org/10.1139/z06-173.

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In various animal species, male sexual dimorphic characters may be used during intrasexual contests as ornaments to attract females, or to hold them before, during, or after copulation. In the well-known harvestman, Phalangium opilio L., 1758, the behavioral functions of these male sexually dimorphic structures have never been studied in detail. Therefore, in addition to a morphometric study, 21 male contests and 43 sexual interactions were analyzed. Our observations revealed that during contests, the male cheliceral horns form a surface by which the contestants use to push each other face-to-face while rapidly tapping their long pedipalps against the pedipalps of the opponent, occasionally twisting the opponent’s pedipalp. Scanning electron micrographs revealed contact mechanoreceptors on the pedipalp that would detect the intensity–frequency of contact with the contender’s pedipalp. Larger males won almost all contests, whereas the loser rapidly fled. During sexual interactions, the longer pedipalps of the male held legs IV of the female, whereas males with shorter pedipalps held the female by legs III. No contact with the male pedipalps and chelicerae by the females was visible before, during, or after copulation. Soon after copulating, males typically bent over the female, positioning their cheliceral horns against the females’s dorsum. Consequently, our data show that the cheliceral horns and the longer pedipalps of the male seem to play an important role, during both intersexual and intrasexual encountering.
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34

PARISH, AMY R., FRANS B. M. DE WAAL, and DAVID HAIG. "The Other “Closest Living Relative”: How Bonobos (Pan paniscus) Challenge Traditional Assumptions about Females, Dominance, Intra- and Intersexual Interactions, and Hominid Evolution." Annals of the New York Academy of Sciences 907, no. 1 (January 25, 2006): 97–113. http://dx.doi.org/10.1111/j.1749-6632.2000.tb06618.x.

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35

Millam, James, Tracey Spoon, and Donald Owings. "Variation in the stability of cockatiel (Nymphicus hollandicus) pair relationships: the roles of males, females, and mate compatibility." Behaviour 141, no. 10 (2004): 1211–34. http://dx.doi.org/10.1163/1568539042729711.

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AbstractPair relationships and their emergent properties represent potentially significant sources of proximate and ultimate influence on mating systems, but the study of such relational factors has been rare compared to the volume of literature dedicated to individual-level measures of mate quality. This study assessed variation in the stability of pair relationships in cockatiels (Nymphicus hollandicus) and sought sources for that variation in both the behavior of mated individuals and their compatibility. Pair relationships represent an especially salient aspect of the social system of cockatiels, a socially monogamous species with long-term pairing.In a semi-natural, captive setting, this study compared (1) the social interactions between cockatiel mates to those individuals' interactions with opposite-sex non-mates, (2) the roles of males and females in pair relationships, and (3) the various pairs in their displays of intrapair and extrapair interactions. We also assessed the behavioral features underlying pair relationships by examining the interrelationships among social behaviors within pairs and the degree to which emergent properties structure pair relationships. Interactions between mates, as compared to opposite-sex non-mates, were characterized by closer proximity, greater behavioral synchrony, less aggression, more allopreening, and greater sexual behavior. Males and females displayed little dimorphism in many intrapair and extrapair behaviors; however, males approached and courted their mates more than females did, and males but not females exhibited more intersexual aggression to non-mates than to their mates. Social interactions between mates varied significantly among pairs in ways that reflected variation in the degree of behavioral compatibility between mates. In other words, suites of highly correlated behaviors characterized the interactions between mates such that pairs exhibiting greater affiliative or accordant behaviors exhibited less aggressive or discordant behaviors and vice versa. Emergent properties appeared to play an especially important role in compatibility. By examining significant within-species variation in pair relationships, this study complements the increasing knowledge of mating relationships gained from comparative studies and illustrates the importance of emergent, pair-level behavior in the maintenance of long-term monogamous pair-bonds.
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36

Rossi, Nicola, Margarita Chiaraviglio, and Gabriela Cardozo. "Behavioural plasticity in activity and sexual interactions in a social lizard at high environmental temperatures." PLOS ONE 18, no. 7 (July 26, 2023): e0285656. http://dx.doi.org/10.1371/journal.pone.0285656.

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Анотація:
Sexual selection often shapes social behavioural activities, such as movement in the environment to find possible partners, performance of displays to signal dominance and courtship behaviours. Such activities may be negatively influenced by increasing temperatures, especially in ectotherms, because individuals either have to withstand the unfavourable condition or are forced to allocate more time to thermoregulation by increasing shelter seeking behaviour. Thus, they “miss” opportunities for social and reproductive interactions. Moreover, behavioural displays of ectotherms closely depend on temperature; consequently, mate choice behaviours may be disrupted, ultimately modifying sexual selection patterns. Therefore, it would be interesting to elucidate how increasing temperatures associated with global warming may influence activity and social interactions in the species’ natural habitat and, specifically how high temperatures may modify intersexual interactions. Consequently, our aim was to explore differences in the daily pattern of social interactions in an ectotherm model, Tropidurus spinulosus, in two thermally different habitats and to determine how high temperatures modify mate choice. High environmental temperatures were found to be associated with a bimodal pattern in daily activity, which was closely linked to the daily variations in the thermal quality of the habitat; whereas the pattern and frequency of social displays showed less plasticity. The time allocated to mate choice generally decreased with increasing temperature since individuals increased the use of thermal refuges; this result supports the hypothesis of “missed opportunities”. Moreover, at high temperatures, both sexes showed changes in mate selection dynamics, with females possibly “rushing” mate choice and males showing an increase in intermale variability of reproductive displays. In our ectotherm model, plastic adjustments in the behavioural activity pattern induced by high temperatures, plus the modification of the displays during courtship may ultimately modify mate choice patterns and sexual selection dynamics.
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37

Sandoval-Molina, Mario A., Bernardo Rafael Lugo-García, Alan Daniel Mendoza-Mendoza, and Mariusz Krzysztof Janczur. "Females restrict the position of domatia and suffer more herbivory than hermaphrodites in Myriocarpa longipes, a neotropical facultative myrmecophyte." Journal of Tropical Ecology 38, no. 2 (December 28, 2021): 99–105. http://dx.doi.org/10.1017/s0266467421000584.

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AbstractDomatia are hollow structures in plants occupied by ant colonies, in turn ants provide protection against herbivores. In plants, competition for resources has driven sex-related changes in the patterns of resource allocation to life-history traits and defence traits. The resource-competition hypothesis (RCH) proposes that female plants due to their higher investment in reproduction will allocate fewer resources to defence production, showing greater herbivore damage than other sexual forms. We hypothesise the existence of sex-related differences in defensive traits of domatia-bearing plants, being female plants less defended due to differences in domatia traits, such as size, number of domatia and their position, exhibiting more herbivore damage than hermaphrodite plants of Myriocarpa longipes, a facultative neotropical myrmecophyte. We found eight species of ants inhabiting domatia; some species co-inhabited the same plant, even the same branch. Our results are consistent with the predictions of RCH, as female plants had ant-inhabited domatia restricted to the middle position of their branches and exhibited greater herbivore damage in leaves than hermaphrodites. However, we did not find differences in domatia size and leaf area between sexual forms. Our study provides evidence for intersexual differences in domatia position and herbivory in a facultative ant–plant mutualism in M. longipes. We highlight the importance of considering the plant sex in ant–plant interactions. Differences in resource allocation related to sexual reproduction could influence the outcome of ant–plant interactions.
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38

Nordeide, Jarle Tryti. "Do male sticklebacks prefer females with red ornamentation?" Canadian Journal of Zoology 80, no. 8 (August 1, 2002): 1344–49. http://dx.doi.org/10.1139/z02-116.

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Анотація:
In general, females are less ornamented than males and until recently female ornaments have been regarded as non-adaptive correlated effects of selection on males. This view is challenged and the alternative hypothesis that females' ornaments have evolved independently of male showiness, by intersexual selection for example, is supported. I tested these hypotheses experimentally using threespine sticklebacks (Gasterosteus aculeatus) from a population in which both sexes have red pelvic spines. Two females differing in red spine colour extravagance were presented simultaneously to a male under white and green light, and the male's courtship activity towards each female was quantified. Green light prevented the use of red cues by sticklebacks. The results show that red colour on the pelvic spines of female sticklebacks has value as a signal to males in this population, and males actually courted females with drab pelvic spines more than females whose pelvic spines had a redder hue, but only when illuminated by white light. The interpretation that best accounts for this result is that spine colour has a strong function in male–male aggressive interactions. This interpretation favours the hypothesis of non-adaptive correlation that has been proposed to explain the evolution of red spines in female sticklebacks.
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39

Vasey, Paul. "Female Choice and Inter-Sexual Competition for Female Sexual Partners in Japanese Macaques." Behaviour 135, no. 5 (1998): 579–97. http://dx.doi.org/10.1163/156853998792897897.

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Анотація:
AbstractObservations of a captive colony of Japanese macaques (Macaca fuscata) were carried out with the goal of documenting (1) competition between males and females for female sexual partners and (2) choice of same-sex sexual partners by females, despite the presence of motivated, opposite-sex alternatives. Data were collected during 21 homosexual consorts hips involving 14 females living in a mixed-sex group of 37 individuals. Intersexual competition for female sexual partners was manifested when a sexually motivated male and female (competitors) simultaneously sought exclusive access to the same infertile or post-conception female (focus of competition). This occurred during male intrusions on female homosexual consortships and counter-challenges by female competitors against intruding males. Inter-sexual competition for female sexual partners took the form of approaches and solicitations directed at the focus of competition, as well as displacements and aggression directed at one's competitor. Females did not acquire alloparental care for their immature offspring from their same-sex consort partners. Thus, female competitors appeared to engaged in potentially risky competition for same-sex sexual partners in the absence of any obvious reproductive benefit (e.g. insemination or alloparental care). Following these interactions, females which were foci of competition chose to mount with the female competitors significantly more often than not.
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40

Bennett, A. M., M. Keevil, and J. D. Litzgus. "Demographic differences among populations of Northern Map Turtles (Graptemys geographica) in intact and fragmented sites." Canadian Journal of Zoology 87, no. 12 (December 2009): 1147–57. http://dx.doi.org/10.1139/z09-105.

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Анотація:
Habitat fragmentation is a leading cause of reptile declines worldwide. We examined demographic differences between populations of Northern Map Turtles, Graptemys geographica (Le Sueur, 1817), inhabiting intact and fragmented sites along the Trent–Severn Waterway (TSW) in Ontario over two field seasons. We examined population densities, sex ratios, body size, and growth rates in two control sites and two fragmented sites (where the waterway is disrupted by dams). We predicted that population density would be higher in control sites, and that sex ratios would differ among sites. Abundance was greater than expected, but densities could not be compared owing to a lack of recaptures. Sex ratios in control sites were slightly male-biased and were significantly female-biased in fragmented sites. Turtles in fragmented habitats were significantly smaller than those in control habitats. Estimated growth rates of juveniles and males were significantly reduced in fragmented populations compared with controls. We hypothesize that habitat alterations in fragmented sites are differentially affecting demographic classes because of the intersexual niche divergence observed in Map Turtles. We emphasize the need for further research to examine the interactions between habitat alteration and invasive species and the effects they are having on Northern Map Turtle populations.
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41

Long, Tristan A. F., Robert Montgomerie, and Adam K. Chippindale. "Quantifying the gender load: can population crosses reveal interlocus sexual conflict?" Philosophical Transactions of the Royal Society B: Biological Sciences 361, no. 1466 (January 4, 2006): 363–74. http://dx.doi.org/10.1098/rstb.2005.1786.

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Анотація:
Six sister populations of Drosophila melanogaster kept under identical environmental conditions for greater than 600 generations were reciprocally crossed to investigate the incidence of population divergence in allopatry. Population crosses directly influenced fitness, mating frequency, and sperm competition patterns. Changes in both female remating rate and the outcome of male sperm competition (P 1 , P 2 ) in response to foreign males were consistent with intersexual coevolution. Moreover, seven of the 30 crosses between foreign mates resulted in significant reductions in female fitness, whereas two resulted in significant increases, compared to local matings. This tendency for foreign males to reduce female fitness may be interpreted as evidence for either sexually antagonistic coevolution or the disruption of mutualistic interactions. However, instances in which female fitness improved via cohabitation with foreign males may better reveal sexual conflict, signalling release from the cost of interacting with locally adapted males. By this metric, female reproduction in D. melanogaster is strongly constrained by local adaptation by males, a situation that would promote antagonistic coevolution between the sexes. We conclude that sexual selection can promote population differentiation in allopatry and that sexual conflict is likely to have played a role in population differentiation in this study system.
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Kreutzer, Michel, Laurent Nagle, and Eric Vallet. "Sexual Responsiveness of Female Canaries To Song Bout Organization." Behaviour 129, no. 3-4 (1994): 293–305. http://dx.doi.org/10.1163/156853994x00659.

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AbstractRecent experiments demonstrated that in oscine species, 1) Some special sequences of multipartite songs convey more sexual information than others and 2) Stimulus change or switching is often associated with intersexual interactions. We looked for an influence of these two song cues in common domesticated canaries. Female canaries were tested for their sexual copulation solicitation display (CSD) in response to the playbacks of different strings of song sequences from males of the same breed. In order to induce habituation, three monotonous strings were created: A.A.A.A.A.A; B.B.B.B.B.B and C.C.C.C.C.C. (repetition of the same song sequence). In order to manage disrupt of habituation by stimulus changes, four types of strings including two types of song sequences were created: B.B.B.A.A.A., A.A.A.B.B.B., C.C.C.B.B.B. and B.B.B.C.C.C. We found that a monotonous repetition of the same sequence leads to habituation when the sexual potency of the sequence is high (sequences A and B) and that song sequences may greatly differ in eliciting sexual displays (A >B>C). Subsequent stimulus change may elicit an immediate response recovery. But such a disrupt of habituation occurs only if a prefered sequence follows a non prefered one. We discuss prominent parameters that may have influenced female sensitivity and responsiveness to string organization in domesticated canaries.
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43

Hood, Kayleigh E., Eden Long, Eric Navarro, and Laura M. Hurley. "Playback of broadband vocalizations of female mice suppresses male ultrasonic calls." PLOS ONE 18, no. 1 (January 5, 2023): e0273742. http://dx.doi.org/10.1371/journal.pone.0273742.

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Анотація:
Although male vocalizations during opposite- sex interaction have been heavily studied as sexually selected signals, the understanding of the roles of female vocal signals produced in this context is more limited. During intersexual interactions between mice, males produce a majority of ultrasonic vocalizations (USVs), while females produce a majority of human-audible squeaks, also called broadband vocalizations (BBVs). BBVs may be produced in conjunction with defensive aggression, making it difficult to assess whether males respond to BBVs themselves. To assess the direct effect of BBVs on male behavior, we used a split-cage paradigm in which high rates of male USVs were elicited by female presence on the other side of a barrier, but which precluded extensive male-female contact and the spontaneous production of BBVs. In this paradigm, playback of female BBVs decreased USV production, which recovered after the playback period. Trials in which female vocalizations were prevented by the use of female bedding alone or of anesthetized females as stimuli also showed a decrease in response to BBV playback. No non-vocal behaviors declined during playback, although digging behavior increased. Similar to BBVs, WNs also robustly suppressed USV production, albeit to a significantly larger extent. USVs suppression had two distinct temporal components. When grouped in 5-second bins, USVs interleaved with bursts of stimulus BBVs. USV suppression also adapted to BBV playback on the order of minutes. Adaptation occurred more rapidly in males that were housed individually as opposed to socially for a week prior to testing, suggesting that the adaptation trajectory is sensitive to social experience. These findings suggest the possibility that vocal interaction between male and female mice, with males suppressing USVs in response to BBVs, may influence the dynamics of communicative behavior.
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44

Selakovic, Sara, Nemanja Stanisavljevic, Vukica Vujic, Luka Rubinjoni, Zivko Jovanovic, Svetlana Radovic, and Dragana Cvetkovic. "Light and sex interplay: Differential herbivore damage in sun and shade in dioecious Mercurialis perennis." Archives of Biological Sciences 70, no. 3 (2018): 469–79. http://dx.doi.org/10.2298/abs171207007s.

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Interactions between plants and herbivorous insects can be shaped by light environment, resulting in differential herbivory in sun and shade. In dioecious species, the combination of plant sex and light-induced changes in defense traits and nutritive value can alter the patterns of foliar damage. We explored the combined effects of light environment and plant sex on natural herbivore damage and plant traits in the dioecious understory forb Mercurialis perennis on Mt. Kopaonik (Serbia). The role of plant traits in predicting the extent of damage was examined as well. Male and female plants from contrasting light environments (shade vs. sun) were analyzed with respect to leaf damage, as well as plant morphological and biochemical traits (size, specific leaf area, carbon-based defensive compounds and nutritional quality). We found prominent differences in herbivore damage between sun and shade conditions, but not between the sexes. Plants from the sun-exposed site had a significantly larger leaf area removed. The specific leaf area co-varied with herbivore damage in an inverse fashion, while leaf nutritional value had a moderate effect. Contrasting light conditions influenced the patterns of intersexual differences in the contents of condensed tannins and soluble proteins, with females exhibiting higher trait values. We found that factors defining risk of consumption were related to plant morphological traits and nutritive value rather than to chemical defenses.
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45

Monamy, V. "Sexual Differences in Habitat Use by Rattus lutreolus (Rodentia: Muridae): The Emergence of Patterns in Native Rodent Community Structure." Australian Mammalogy 20, no. 1 (1998): 43. http://dx.doi.org/10.1071/am97043.

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The successful long-term conservation of Australian fauna relies on a clear understanding of how coexisting species partition limited resources. Such partitioning results in complex levels of habitat selection, dependent on dynamic interactions between biotic and abiotic processes. In small mammal communities where native Rattus spp. are present and there are substantial interspecific competitive effects, habitat selection by female Rattus may drive habitat use by other rodent species (particularly native mice). This has been demonstrated in Tasmania where the velvet-furred rat, R. lutreolus velutinus, and the long-tailed mouse, Pseudomys higginsi, occupy wet sclerophyll forest in sympatry. Differential habitat use is exhibited by male and female R. l. velutinus which may determine the extent of habitat use by P. higginsi. Here, I report a similar pattern of coexistence between the swamp rat, R. l. lutreolus, and the eastern chestnut mouse, P. gracilicaudatus, in coastal heathland in New South Wales. As in the Tasmanian model, female R. l. lutreolus were significantly more likely to be trapped in areas of densest vegetation, and male R. l. lutreolus and both sexes of P. gracilicaudatus were more often trapped in areas where cover was less dense. This finding introduces the possibility that there exists a clear and possibly widespread mechanism of coexistence that involves intersexual differences in habitat use by the dominant species in communities where substantive interspecific competition has been demonstrated.
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46

Stewart, Ian R. K., and David F. Westneat. "Production Of Melanin-Based Plumage Traits In Male House Sparrows: No Effect Of Dietary Copper." International Studies on Sparrows 35, no. 1 (December 1, 2011): 4–15. http://dx.doi.org/10.1515/isspar-2015-0006.

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Abstract In many bird species, males possess conspicuous patches of black feathers on their head or breast, the size of which is often positively related to their success in intra- and intersexual interactions. The production of these plumage signals is presumed to depend upon one or more limiting factors which prevent low quality males developing large signals in order to gain the associated benefits. The coloration of these feathers is due to their infusion with the pigment melanin, which birds synthesize endogenously during a series of conversion steps beginning with the enzymatic oxidation of the amino acid tyrosine. Copper is the cofactor of the enzyme responsible for this process, and it is possible that copper level limits the activity of the enzyme and therefore limits melanin production. We tested this hypothesis by manipulating the level of dietary copper available to individually caged juvenile and adult house sparrows (Passer domesticus) throughout their moult. Birds were provided with artificial diets containing either 100%, 50% or 10% of the recommended level of copper. Dietary copper did not affect the size of the black breast patch, the most obvious melanin-based plumage trait in this species, nor did it affect the reflectance of the black feathers. In sum, we reject the hypothesis that dietary copper limits the size or blackness of the breast patch of the male house sparrow.
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47

Vasconcelos, Raquel, Sara Rocha, and Xavier Santos. "Sharing refuges on arid islands: ecological and social influence on aggregation behaviour of wall geckos." PeerJ 5 (January 10, 2017): e2802. http://dx.doi.org/10.7717/peerj.2802.

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BackgroundThe extent of social behaviour among reptiles is underappreciated. Two types of aggregations are recognized in lizards: ecological and social, i.e., related to the attraction to a site or to animals of the same species, respectively. As most lizards are territorial, aggregations increase the probability of aggressive interactions among individuals, a density-dependent behaviour.MethodsAfter some spurious observations of aggregation behaviour in the endemic Cabo Verde nocturnal geckoTarentola substituta,we conducted a field-based study in order to thoroughly characterize it. We sampled 48 transects and 40 10 × 10 m quadrats on São Vicente Island to describe the incidence, size and composition of aggregations and to study the effect of gecko and refuge density, plus refuge quality, on refuge sharing. We hypothesize that when density of animals and scarcity of high-quality refuges is higher, lizards have increased probability of aggregating. We also predict a consistent pattern of size and composition of groups (male–female pairs, only one adult male per group) throughout the year if there is a selected behaviour to avoid agonistic interactions, and low thermal advantage to aggregating individuals.ResultsWe present one of the first evidences of aggregation for Phyllodactylidae geckos. We found thatT. substitutaforms aggregations around 30–40% of the time, and that refuges are almost always shared by a female-male pair, sometimes with a juvenile, probably a mechanism to avoid aggressive interactions. We also observed that refuge sharing is dependent on refuge quality, as medium–large (thermally more stable and positively selected) rocks are shared much more frequently than small ones, but independent of adult sizes. Refuge sharing is also directly related to the density of geckos and inversely related to the density of high-quality refuges. We found no relation between body temperatures of geckos and refuge sharing when controlling the effect of rock/air temperature, suggesting that huddling does not improve thermoregulation.DiscussionOur results suggest that in this harsh environment (rocks reach 46 °C) aggregation incidence is mainly driven by an ecological factor (scarcity of high-quality refuges) and its intersexual composition by social factors (avoidance of agonistic interactions by males, and possible increased reproductive success of the pair). This study sheds some light on the little explored gecko aggregation behaviour and other studies should follow.
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48

Angell, Christopher S., Sharon Curtis, Anaïs Ryckenbusch, and Howard D. Rundle. "Epicuticular Compounds of Protopiophila litigata (Diptera: Piophilidae): Identification and Sexual Selection Across Two Years in the Wild." Annals of the Entomological Society of America 113, no. 1 (November 24, 2019): 40–49. http://dx.doi.org/10.1093/aesa/saz056.

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Abstract The epicuticular compounds (ECs) of insects serve both to waterproof the cuticle and, in many taxa, as pheromones that are important for various social interactions, including mate choice within populations. However, ECs have not been individually identified in many species and most studies of their role in mate choice have been performed in a laboratory setting. Here we newly identify and quantify the ECs of the antler fly, Protopiophila litigata Bonduriansky, and use a cross-sectional selection analysis to quantify their association with male mating success in the wild across two years (2013 and 2017). The ECs of antler flies include straight-chain and methylated alkanes, alkenes, and a family of branched wax esters. We find all ECs to be shared between males and females but also demonstrate sexual dimorphism in the abundance of several. Male EC relative abundances were significantly associated with mating success in both years, although the multivariate direction of selection differed significantly between the years. Surprisingly, only two of the 18 compounds (or groups of compounds) we identified were similarly associated with mating success across the sampling years. In 2017, we further partitioned sexual selection into intra- and intersexual components, revealing selection on ECs to be significant via female choice but not male–male competition. Our study is one of few to investigate the potential role of ECs in mating success in the wild and adds to a growing body of evidence demonstrating significant temporal variability in selection in natural populations.
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49

Galoyan, Eduard A. "Unstable social structure indicates low diversity of relationships in the spotted forest skink Sphenomorphus maculatus." Amphibia-Reptilia 38, no. 3 (2017): 381–93. http://dx.doi.org/10.1163/15685381-00003118.

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To the date, we hardly understand what and how affects the social structure in animals. Longevity and social stability must be the key factors influencing the relations among individuals. To test this suggestion, I described the spatial and social structures of the spotted forest skinks (Sphenomorphus maculatus) from southern Vietnam in the breeding seasons of 2008 and 2009. This species is known to have short lifespan and low social stability among seasons. No difference between male and female space use was revealed. Home ranges were 107.7 ± 23.68 m2 in males and 78.9 ± 27.27 m2 in females, and these contained core areas and activity centres within them. Home ranges and their parts overlapped among individuals of all sexes and were used by several residents, although not at the same time. Intrasexual and intersexual relationships were agonistic, more aggressive among males, and characterized by hierarchy with males as dominants and females as subordinates. Dominance status in males was supported by aggression in males and by submission in females. Females avoided sexual encounters, and no affiliation between sexes or mate guarding behaviour were revealed. A poor social behavioural repertoire was limited by aggressive and submissive behaviour, and it was difficult to distinguish sexual courtship from agonistic interactions. Hence, social and spatial structures were relatively simple in comparison with other saurian species and low stability of social composition is the most probable reason of such a social simplicity.
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50

Cooke, Raylene, Rohan Bilney, and John White. "Potential competition between two top-order predators following a dramatic contraction in the diversity of their prey base." Animal Biology 61, no. 1 (2011): 29–47. http://dx.doi.org/10.1163/157075511x554400.

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AbstractTwo sympatric native top-order predators, the sooty owl (Tyto tenebricosa tenebricosa) and powerful owl (Ninox strenua) coexist throughout much of their range in south-eastern Australia. Following European settlement, however, major changes in resource availability for these predators potentially resulted in increased competition, especially for food. This study examined ecological attributes of both species, including intersexual differences in the sooty owl, potential resource partitioning and whether competition may be occurring. Dietary overlap was high between female sooty owls and powerful owls (0.90), compared to overlap between male sooty owls and powerful owls (0.67), with three mammalian species contributing over 74% of their diets. Sooty and powerful owls coexisted throughout the study region, regularly roosting within the same vegetation types, and in similar locations, although microhabitat differences were apparent. Sooty owls displayed aseasonal breeding, although a peak in fledging in spring coincided with powerful owl breeding. Both species exclusively nested in similar size mountain grey gums (Eucalyptus cypellocarpa), however, hollow characteristics differed slightly. Significant divergence along a single niche dimension was not detected between powerful and sooty owls, as they had similar diets, habitat usage and activity times, potentially resulting in competition. Reproductive output was low for both species, however, the degree to which competitive interactions influenced this remains unknown. To minimise potential competition, longterm feral predator control and improved habitat management is recommended to increase the density and diversity of small terrestrial mammals, as this should result in diversification of the sooty owl diet, reducing dietary overlap with powerful owls.
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