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331.
Ximena E. Bernal Karin L. Akre Alexander T. Baugh A. Stanley Rand Michael J. Ryan 《Behavioral ecology and sociobiology》2009,63(9):1269-1279
We investigated the natural dynamics in a sexual signal that combines different call components and explored the role of call
complexity in sexual selection using a neotropical frog. Male túngara frogs, Physalaemus pustulosus, facultatively add up to seven short, multi-harmonic components (chucks) to the simple form of their calls (whines). Female
túngara frogs are preferentially attracted to whines with chucks over whines without chucks, and males also call more in response
to calls containing chucks. Because acoustic predators prefer complex calls, in the context of simple (no chucks) versus complex
(any number of chucks) calls, the variably complex call appears to have evolved in response to the opposing selective forces
of natural and sexual selection. There is no evidence, however, for the function of increasing the number of chucks within
complex calls. We tested two aspects of increasing call complexity: natural patterns of use of call types in males and how
both sexes respond to variation in multi-chuck calls. Males incrementally change call complexity by the addition or subtraction
of a single chuck and usually do not produce more than two chucks. Variation in call complexity, for calls with at least one
chuck, does not influence response calling in males or phonotaxis in females. Our results suggest that one reason for not
increasing call complexity beyond a single chuck is the diminishing effectiveness on the responses of both sexes.
This is a posthumous publication for A. Stanley Rand 相似文献
332.
Tom Tregenza Fathi Attia Saleh Salem Bushaiba 《Behavioral ecology and sociobiology》2009,63(6):817-823
Differences among males in their success in achieving fertilisations when females mate with more than one partner are now
recognised as an important target of sexual selection. However, very few studies have attempted to determine whether particular
males are consistently successful in sperm competition and whether success in sperm competition is a heritable trait. Additionally,
the potential heritability of female traits that influence the outcome of sperm competition has received only limited attention.
Using the polyandrous beetle Tribolium castaneum, we examined repeatability of male success in sperm competition by mating pairs of males carrying different visible genetic
markers to a string of different females. Males showed consistency in their ability to successfully transfer sperm to females,
but not in their success in sperm competition. Furthermore, when we independently compared success in sperm competition of
fathers with their sons, we found no evidence for heritability of this trait. Similarly, females that exhibited high or low
first male sperm precedence did not tend to have daughters that showed the same pattern. Our results suggest that we should
be wary of assuming that success in sperm competition is heritable through either sex. 相似文献
333.
黄淮海平原农区不同类型农户的土地利用方式选择及其环境影响——以河北省曲周县为例 总被引:37,自引:0,他引:37
以农户调查为基础,采用农户分类和方差分析等方法,对农户土地利用方式选择行为及其环境影响进行对比分析。受其兼业性、收入水平、文化素质和生产规模影响,不同类型的农户在地块尺度的土地利用方式选择存在差异:纯农业户、低收入农户的土地利用方式选择具有多元化的特征,兼业户、高收入农户、文化水平高的农户往往选择经济效益高、耗时少的土地利用方式。不同类型农户由于其土地利用方式及其肥料投入、水资源利用和秸秆处理等的不同,对土地质量和环境变化产生不同的影响。 相似文献
334.
Peter D. Dijkstra Els M. van der Zee Ton G. G. Groothuis 《Behavioral ecology and sociobiology》2008,62(5):747-755
Mate preferences on male colour have been implicated in generating and maintaining species diversity among haplochromine cichlid
fish. Their lek-like mating system suggests that not only male colour but also territory quality is instrumental in mate choice.
We assessed the relative importance of territory quality and male colour in mate choice by testing whether territory quality
can override the female preference for males of her own colour in the Lake Victoria cichlid genus Pundamilia. First, we showed in experimental groups that the dominant male preferentially monopolised a large tube relative to a small
tube. The situation mimics quality difference in rocky crevices that serves as a focal point for male courtship display. Second,
in mate-choice tests, Pundamilia nyererei females were allowed to choose between closely related P. nyererei and P. pundamilia males; these species differ strikingly in male nuptial coloration, but little else. We gave either both males the same small
tube or one of them a large tube. The preference of P. nyererei females for P. nyererei males in the control situation (where both males had a small tube) was significantly diminished in favour of P. pundamilia males when the latter had the large tube. The results provide experimental evidence that differences in territory quality
can override the female preference for males of her own colour. This finding is critical for a recent hypothesis proposing
that male competition for mating territories can facilitate the process of sympatric speciation by sexual selection. 相似文献
335.
Many species base their choice of mates on multiple signals which provide them with different kinds of information. Choosers
may assess the signals together to evaluate the overall quality of potential mates, but individuals often pay attention to
different signals in different contexts. In Rhinogobius brunneus, a fish displaying exclusive male parental care, females generally prefer males showing larger first dorsal fins (FDF) and
more active courtship displays as mates. Females choosing a mate usually initially assess the FDF and later utilize courtship
for the final decision. In our experiments, females with different hunger states used different signals when selecting mates.
Females in both hunger states preferred males with larger FDF in the first stage. In the second stage, well-fed females showed
highly repeatable choice, whereas poorly fed females responded only to variation in the courtship activity of males. The males
preferred by poorly fed females exhibited significantly higher offspring survival than nonpreferred males. Under conditions
of food shortage, males allocate more energy to future reproduction at the expense of the present brood, and females may prioritize
signals predictive of offspring survivorship over signals reflecting other aspects in male quality to minimize the losses
in direct benefits. We conclude that R. brunneus females may employ information from both signals but dynamically adjust their prioritization of each signal to current conditions
to ensure the choice that is currently most adaptive. 相似文献
336.
Ioana Chiver Bridget J. M. Stutchbury Eugene S. Morton 《Behavioral ecology and sociobiology》2008,62(12):1981-1990
Extra-pair fertilizations are common in many socially monogamous species, and paternity studies have indicated that females
may use male vocal performance and plumage ornaments as cues to assess male quality. Female off-territory forays may represent
a key component of female choice and male extra-pair mating success, and female foray behaviour is expected to be strongly
influenced by indictors of male quality. In this study, we examined how male song and ornamentation affect how often females
left their territories, which males they visited and extra-pair paternity in a socially monogamous passerine, the hooded warbler
(Wilsonia citrina). We radiotracked 17 females during the fertile period and quantified male vocal performance (song output and rate) and plumage
characteristics (size of the black melanin hood and colour of the black hood, yellow cheeks and breast areas). We obtained
blood samples and determined paternity at 35 nests including those of 14 females that we radiotracked. Eleven (65%) of the
17 females forayed off-territory, whilst fertile and female foray rate was positively correlated with the number of extra-pair
young in the nest. Females that left their territories more frequently were paired with males that sang at a low rate. In
addition, extra-pair mates had higher song rates than the social mates they cuckolded (5.3 songs/min vs. 4.4 songs/min). Female
off-territory forays or extra-pair paternity were not significantly related to male plumage characteristics. Our results indicate
that a high song rate influences both the foray behaviour of a male’s social mate and the likelihood that he will sire extra-pair
offspring with neighbouring females. 相似文献
337.
Effective public expenditure currently dominates the management focus of many protected areas. This calls for explicit modeling of constraints and motivations that, respectively, obstruct and stimulate visits to selected outdoor destinations. Choice set formation is the result of screening and/or inclusion of specific sites (alternatives) to form the set of sites considered in real choices. Evidence shows that the omission of a structural representation of choice set formation is harmful to econometric inference. Yet, the literature has largely ignored the underlying behavioral phenomenon. We show, using a discrete choice experiment involving selection among seven recreational sites in an Italian national park, that choice set formation is behaviorally relevant, even after controlling for preference discrimination. Motivations (why visit?) are important determinants of preliminary site screening for choice set inclusion, as well as site selection, justifying the additional value of such modeling extension. 相似文献
338.
Diana Emang Thomas Hedemark Lundhede Bo Jellesmark Thorsen 《Journal of Environmental Planning and Management》2017,60(11):1993-2012
Preference elicitation among outdoor recreational users is subject to measurement errors that depend, in part, on survey planning. This study uses data from a choice experiment survey on recreational SCUBA diving to investigate whether self-reported information on respondents’ comfort when they complete surveys correlates with the error variance in stated choice models of their responses. Comfort-related variables are included in the scale functions of the scaled multinomial logit models. The hypothesis was that higher comfort reduces error variance in answers, as revealed by a higher scale parameter and vice versa. Information on, e.g., sleep and time since eating (higher comfort) correlated with scale heterogeneity, and produced lower error variance when controlled for in the model. That respondents’ comfort may influence choice behavior suggests that knowledge of the respondents’ activity patterns could be used to plan the timing of interviews to decrease error variance in choices and, hence, generate better information. 相似文献
339.
Jürgen Meyerhoff Alexandra Dehnhardt Volkmar Hartje 《Journal of Environmental Planning and Management》2010,53(1):107-124
Many inhabitants of Berlin enjoy bathing in lakes and rivers during the summer. However, so far no data exist about who goes bathing and what quality bathers expect from bathing sites. In an online survey conducted during the summer of 2007 respondents were presented with a choice experiment concerning various attributes of bathing sites such as water quality or cleanliness of the beach. Applying both random parameter logit models as well as a latent class model reveals that unobserved taste heterogeneity is present among bathers, i.e. not all bathers would benefit equally from improving bathing sites. A test concerning preference consistency reveals high internal validity. 相似文献
340.