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171.
Facultative traits that have evolved under sexual selection, such as the acoustic ornaments present in the advertisement signals
of male túngara frogs (Physalaemus pustulosus), offer a unique opportunity to examine selection for trait exaggeration with a focus on individual differences amongst signalers.
By contrast, many studies of mate choice use experimental designs that obscure the inter-individual variation amongst signalers
available for selection to act on—through the use of “typical” or average signals from the population. Here, we use dichotomous
female phonotaxis choice tests to determine how the value of male call embellishment varies across 20 individual males frogs
recorded from the wild—a sample which captures the acoustic diversity present in the population. We tested 20 females for
each male call pair (i.e., 400 females). The results show widespread preference amongst females for ornamented calls (“whine–chucks”)
over simple calls (“whines”), yet also demonstrate substantial variation in the relative benefits for individual male frogs—some
males enjoy appreciable benefits by using ornaments while others (30% of males in this study) do not. We also show that the
relative amplitude of the chuck to the whine correlates positively with the value of call elaborations across these 20 males.
Finally, by manipulating the relative amplitude of whines and chucks using both natural and synthetic calls, we demonstrate
directly that this single call parameter is key to determining the relative value of call elaborations across males. 相似文献
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Mario Mitov Elitsa Hristova Georgi Hristov Rashko Rashkov Marina Arnaudova Alexander Popov 《Environmental Chemistry Letters》2009,7(3):249-253
NiW systems are known as one of the best catalysts for various desulfurization processes. In this study, we examined catalytic
properties of NiW electrodeposits, produced from two different electrolytes, towards sulfide ion oxidation in alkaline solution.
Despite the big difference in morphology and structure of both materials, they exhibit almost the same catalytic activity
for the examined reaction. A possible explanation of this experimental fact is that the overall reaction is controlled by
the transport of oxygen through the catalyst samples. 相似文献
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Verkerk Pieter J. Lindner Marcus Pérez-Soba Marta Paterson James S. Helming John Verburg Peter H. Kuemmerle Tobias Lotze-Campen Hermann Moiseyev Alexander Müller Daniel Popp Alexander Schulp Catharina J. E. Stürck Julia Tabeau Andrzej Wolfslehner Bernhard van der Zanden Emma H. 《Regional Environmental Change》2018,18(3):817-830
Regional Environmental Change - Plausible scenarios of future land use derived from model projections may differ substantially from what is actually desired by society, and identifying such... 相似文献
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R. Alexander Bentley Paul Ormerod Michael Batty 《Behavioral ecology and sociobiology》2011,65(3):537-546
Darwinian studies of collective human behaviour, which deal fluently with change and are grounded in the details of social
influence among individuals, have much to offer “social” models from the physical sciences which have elegant statistical
regularities. Although Darwinian evolution is often associated with selection and adaptation, “neutral” models of drift are
equally relevant. Building on established neutral models, we present a general, yet highly parsimonious, stochastic model,
which generates an entire family of real-world, right-skew socio-economic distributions, including exponential, winner-take-all,
power law tails of varying exponents, and power laws across the whole data. The widely used Barabási and Albert (1999) Science 286: 509-512 “B-A” model of preferential attachment is a special case of this general model. In addition, the model
produces the continuous turnover observed empirically within these distributions. Previous preferential attachment models
have generated specific distributions with turnover using arbitrary add-on rules, but turnover is an inherent feature of our
model. The model also replicates an intriguing new relationship, observed across a range of empirical studies, between the
power law exponent and the proportion of data represented in the distribution. 相似文献