146 resultados para Mating Preferences

em Deakin Research Online - Australia


Relevância:

100.00% 100.00%

Publicador:

Resumo:

In recent years, it has become evident that frequency dependence in the attractiveness of a particular phenotype to mates can contribute to the maintenance of polymorphism. However, these preferences for rare and unfamiliar male phenotypes have only been demonstrated in small, controlled experiments. Here, we tested the preference for unfamiliar mates in groups of six to 96 individuals over 13 days, in the guppy (Poecilia reticulata). We observed individual behaviour in situ to test whether fish discriminate two unfamiliar individuals among many familiar ones. We found that unfamiliar males and females were preferred over the familiar fishes in all groups and that this effect decayed over time. Increasing group sizes and levels of sexual activity did not hamper the preference for unfamiliar mates, providing further support for the role of frequency dependent mate choice in the maintenance of trait polymorphism in natural populations.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Avian plumage has long been used to test theories of sexual selection, with humans assessing the colors, However, many birds see in the ultraviolet (<400 nm), to which humans are blind, Consequently, it is important to know whether natural variation in UV reflectance from plumage functions in sexual signaling, We show that female starlings rank males differently when UV wavelengths are present or absent, Principal component analysis of approximate to 1300 reflectance spectra (300-700 nm) taken from sexually dimorphic plumage regions of males predicted preference under the UV+ treatment. Under UV- conditions, females ranked males in a different and nonrandom order, but plumage reflectance in the human visible spectrum did not predict choice, Natural variation in UV reflectance is thus important in avian mate assessment, and the prevailing light environment can have profound effects on observed mating preferences.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Captive breeding is a high profile management tool used for conserving threatened species. However, the inevitable consequence of generations in captivity is broad scale and often-rapid phenotypic divergence between captive and wild individuals, through environmental differences and genetic processes. Although poorly understood, mate choice preference is one of the changes that may occur in captivity that could have important implications for the reintroduction success of captive-bred animals. We bred wild-caught house mice for three generations to examine mating patterns and reproductive outcomes when these animals were simultaneously released into multiple outdoor enclosures with wild conspecifics. At release, there were significant differences in phenotypic (e.g. body mass) and genetic measures (e.g. Gst and F) between captive-bred and wild adult mice. Furthermore, 83% of offspring produced post-release were of same source parentage, inferring pronounced assortative mating. Our findings suggest that captive breeding may affect mating preferences, with potentially adverse implications for the success of threatened species reintroduction programmes.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Here, we report for the first time, to our knowledge, a strong correlation between a measure of individual genetic diversity and song complexity, a sexually selected male trait in sedge warblers, Acrocephalus schoenobaenus. We also find that females prefer to mate with males who will maximize this diversity in individual progeny. The genetic diversity of each offspring is further increased by means of nonrandom fertilization, as we also show that the fertilizing sperm contains a haplotype more genetically distant to that of the egg than expected by chance. These findings suggest that species' mating preferences may be subject to fine tuning aimed at increasing offspring viability through increased genetic diversity. This includes external and internal mechanisms of selection, even within the ejaculate of a single male.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The lifespan mating preferences of men and women were examined to determine which of two theories of mate selection, evolutionary and social-role theory, could best explain the findings. Of the 785 respondents surveyed, the lifespan preferences of both men and women supported the evolutionary perspective of mate selection.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The preference of female blue tits, Parus caeruleus, is correlated with the brightness of the ultraviolet (UV) crest; there is also assortative mating with respect to the crest's UV/violet chroma. However, manipulation of plumage reflectance is necessary to infer a direct causal link between UV plumage and mate choice. We gave both male and female blue tits a choice between a W-reflecting ('UV+') partner and a partner whose UV plumage reflectance had been removed ('UV-'). Male blue tits significantly preferred UV+ females. Similarly, female blue tits tended to prefer UV-reflecting males, but their UV+ preferences were nonsignificant. Neither sex showed a preference when conspecifics were replaced by a heterospecific. This study suggests mutual mate choice but male choice may be more strongly influenced by the visual appearance of potential mates. This is one of a few studies to show male mate preferences and the first demonstration of a direct relationship between UV reflectance and;male mate choice. (C) 1999 The Association for the Study of Animal Behaviour.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Using Entwistle and Ramsden's (1983) Approaches to Studying Inventory, Fuller and Chalmers showed little difference between TAFE students and university students both in the factor structures derived through factor analysis, and in a comparison of individual subscale through analysis of variance. Fuller and Chalmers had hypothesised that differences in approaches to study may be identified as a result of the different learning and teaching contexts experienced by the two groups of students. The current study has examined the similarities and differences between students in the two sectors using a learning preferences inventory. Learning preferences were chosen for investigation on the basis of previous theoretical work which suggests that it is preferences that are most influenced by environmental factors. The present study has shown significant similarity between the learning preferences of the two groups of students. However, there were also significant differences which indicate that the Fuller and Chalmers hypothesised differences may be more observable at a preferences level than at an approaches to study level.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The learning preferences of three hundred and thirty eight technology students enrolled in sub-degree programs at an Australian institution of Technical and Further Education were tested using the Canfield Learning Styles Inventory (CLSI). The results have been interpreted in a learning preferences framework and provide supportive evidence for the preferences factors of print-nonprint, collaborative, dependent,and autonomous learning identified by Sadler-Smith & Riding (1999). Although there search focussed on learning preferences the analysis also indicated support for the Wholist-Analytic cognitive style proposed by Riding & Cheema (1991). Gender differences were shown for the Interest subscales of the CLSI. Age-group differences were shown for several Conditions of Learning and Modes of Learning subscales. Implications for the design of training programs, and the skills that may need to be developed in technology learners to enable effective use of flexible delivery, are also discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Lorikeet densities were measured across four habitat types in urban Melbourne. Musk Glossopsitta concinna and Rainbow Lorikeets Trichoglossus haematodus were shown to preferentially use established streetscapes with predominantly native vegetation. The high densities of Musk Lorikeets recorded possibly reflect a paucity of flowering in Victorian BoxIronbark forests during the autumnlwinter of 2002 and the availability of supplementary nectar resources in the urban environment. Future planting decisions in recently developed streetscapes will dictate the long-term resource potential for lorikeets and other nectarivores in urban Melbourne.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Using a sample of 314 Australian university students the Readiness for Online Learning questionnaire was tested for its technical characteristics of reliability and factorability, with results indicating the instrument has promise both for research and for practice. The factor analysis identified a factor associated with self-management of learning, and one of comfort with e-learning. These factors are interpreted and discussed within a framework of the broader literature on learning preferences associated with flexible delivery and resource-based learning.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This research was designed to assess whether teachers and trainers of vocational learners noted and valued differences in individual learning preferences and, if so, how those differences were observed in natural classroom, workshop or other formal learning settings. Data were collected from six vocational education and training (VET) learning sites and included a quantitative questionnaire component and an interview component. The questionnaire data were generated from 160 VET teachers and trainers, and there were 13 interviews with individual teachers. The data show that teachers do make observations of style and preference differences and do respond to those differences. They are pragmatic in the ways that they make the observations and conclusions from them, and they organise their ideas about preferences into those to do with mode of delivery and those to do with learning context. Using these observations and their organisation of them, teachers also continuously modify preconceptions they have about individual learners and groups of learners, and those modifications influence teachers' responses to learners.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Balancing the needs of work and family is a subject of much debate.The purpose of this research was to explore how families manage their children's health within the context of different work and family arrangements.In-depth interviews were conducted with women who were at home full time (8) or in paid work over 30 hours a week (7). Women had at least one child under the five years of age. Findings revealed there was no simple relationship between women's working arrangements and how they managed their children's health. All women, irrespective of their working arrangements, held similar preferences for managing their children's health.However, most women experienced either time or financial constraints that meant they had to compromise their original preferences. In some cases this meant children missed out on receiving health services. Workplace support, extended family support and general satisfaction with work and family arrangements appeared to be important factors for the small number of women who had no problems in managing their children's health. The implications of these findings are discussed.