Vocal imitation and individual recognition of finch calls

American goldfinch females recognize individual males by their individually distinctive flight calls. Goldfinches and other cardueline finch species are also capable of learning new flight calls by imitation during pair and flock formation. Vocal imitation can occur between members of different species as well as between members of the same species. Learning of new flight calls differs in several respects from typical passerine song learning.     

Female responses to ancestral advertisement calls in tungara frogs

Phylogenetic techniques were used to estimate and reconstruct advertisement calls at ancestral nodes. These calls were used to investigate the degree of preference of female túngara frogs (Physalaemus pustulosus) for both extant and ancestral calls. Females did not discriminate between calls of males of their own species and calls at their most recent ancestral node. They also recognized calls of three extant species and at four ancestral nodes as the signals of appropriate mates. Both shared ancestral history, and call convergence might differentially influence call preferences.     

Do frogs communicate with seismic signals?

Male white-lipped frogs exhibit conspicuous behavioral responses to calling conspecific males that are nearby but out of view. Since the calls often are accompanied by strong seismic signals (thumps), and since the male white-lipped frog exhibits the most acute sensitivity to seismic stimuli yet observed in any animal, these animals may use seismic signals as well as auditory signals for intraspecific communication.     

Genetic control of song specificity in crickets

The calling song of male field crickets is composed of stereotyped rhythmic pulse intervals, which are predictable expressions of genotype. Females identify conspecific males by their song. Two species of crickets were found to exhibit species-specific song preference, and hybrids between them preferred hybrid calls over either parental call. These results imply genetic control of song reception as well as transmission.     

Superfast muscles set maximum call rate in echolocating bats

As an echolocating bat closes in on a flying insect, it increases call emission to rates beyond 160 calls per second. This high call rate phase, dubbed the terminal buzz, has proven enigmatic because it is unknown how bats are able to produce calls so quickly. We found that previously unknown and highly specialized superfast muscles power rapid call rates in the terminal buzz. Additionally, we show that laryngeal motor performance, not overlap between call production and the arrival of echoes at the bat's ears, limits maximum call rate. Superfast muscles are rare in vertebrates and always associated with extraordinary motor demands on acoustic communication. We propose that the advantages of rapid auditory updates on prey movement selected for superfast laryngeal muscle in echolocating bats.     

农村电网故障定位系统的设计与实现

提出了一种农村电网故障定位的不精确推理方法，该方法基于用户投诉的不精确信息，采用贝叶斯不精确推理法，可以排除少数错误故障投诉信息的不利影响，最终获得比较可信的故障定位结果。根据这一方法设计了农村电网故障定位系统，典型算例与系统实际运行结果表明，该方法可有效地解决农网故障定位中不确定性问题。     

Dialects in elephatn seals

Threat vocalizations of male elephant seals Mirounga angustirostris vary among four populations on islands off the coast of California and Baja California, Mexico. Males at San Nicolas Island in Southern California emit sound pulses at more than double the rate of males at A?o Nuevo Island, 528 kilometers north. Mean pulse rates at San Miguel Island and Isla de Guadalupe (408 and 944 kilometers south of A?o Nuevo, respectively) are intermediate to these two. Pulse rate is homogeneous within each population and consistent in the same individual. Other properties of the calls which separate populations are pulse duration and embellishment of the initial or terminal pulse in a series. These geographical differences in vocal behavior resemble local dialects in birds and humans.     

Intense Natural Selection in a Population of Darwin's Finches (Geospizinae) in the Galapagos

Survival of Darwin's finches through a drought on Daphne Major Island was nonrandom. Large birds, especially males with large beaks, survived best because they were able to crack the large and hard seeds that predominated in the drought. Selection intensities, calculated by O'Donald's method, are the highest yet recorded for a vertebrate population.     

丹顶鹤与白枕鹤语图结构分析及比较

采用Avisoft SAS-Lab软件对采自哈尔滨北方森林动物园和扎龙自然保护区的笼养丹顶鹤(Grusjaponensis)和白枕鹤(Grus vipio)的鸣声,即繁殖期对鸣、日常短鸣及幼鸟鸣声进行了语图结构分析,对丹顶鹤和白枕鹤的同源声音进行比较发现,它们的对鸣、日常短鸣及幼鸟的鸣声都具有显著的差异:白枕鹤对鸣的单音节持续时间较丹顶鹤短;丹顶鹤日常短鸣的持续时间较长,频率较高。对于幼鸟鸣声,则是白枕鹤幼鸟鸣声持续的时间更长,频率更高。     

Antennae and sexual receptivity in Drosophila melanogaster females

For the female to be normally responsive to the display of wing vibrations by males, the arista and funiculus of the female's antenna must be intact and able to move freely. The arista probably acts as a sail, twisting the funiculus and thus stimulating units of Johnston's organ at its base.     

Hybrid tree frogs: vocalizations of males and selective phonotaxis of females

Male hybrids of reciprocal crosses between gray and pinewoods tree frogs (Hyla chtysoscelis x H. femoralis) that were raised to sexual maturity in the laboratory produced distinctive vocalizations. Hybrid females preferred the calls of hybrids to calls of gray tree frogs and also chose synthetic calls with a pulse repetition rate typical of the hybrids in preference to calls with a rate typical of pinewoods tree frogs.     

Beyond electronic feeding: The implementation of call feeding for pregnant sows

Call feeding for pregnant sows is a novel modular extension of a conventional electronic feeder (PigTek INTEC MAC) communicating via ISOagriNET. The call feeding module (CFM) assigns individual calls to each animal of a group supplied by one feeder and trains them to associate that call with feed access. Afterwards it actively calls sows to the feeder in a variable sequence in order to minimize queuing and thereby reducing aggression, stress and injuries associated with feeding. In this paper, we describe the automatic training procedures, the principal technical design and implementation details that make call feeding applicable in practice. The automatic training consists of an initial Pavlovian conditioning during standard electronic feeding and a subsequent operant conditioning. During Pavlovian conditioning the sows may enter the feeder whenever they have remaining feed allowance. An individual acoustic signal is then played immediately before the feed is dispensed. In the operant training the sow learns by experience that she can enter the feeder only after the individual acoustic signal has been presented. The training modes and their durations are individual to each sow’s learning success. Undersupply with feed due to incomplete learning is prevented by the training routines without manual intervention by controlling automatically the proportion of operant and Pavlovian conditioning. Thus, introducing call feeding in an existing herd is possible. The implementation is further able to estimate roughly the social hierarchy and incorporates this in the calculation of the call sequence in order to attenuate feeding associated aggressions. It helps to provide the animals with a positive anticipation of safe feeding and thereby offers a suitable way to improve welfare and health of pregnant sows. Being automatically controlled, it is easy to apply and has the potential to become a promising future element of precision livestock farming.     

Bat predation and the evolution of frog vocalizations in the neotropics

Bat predation has probably had an important influence on the evolution of frog vocalizations in the Neotropics. The rate at which fringe-lipped bats capture frogs is significantly higher when the frogs are calling. These bats respond to a wide variety of calls from edible frogs, and, when simultaneously presented with a choice, choose the recorded call of a palatable species over that of a poisonous species and the call of a small species over that of one too large to capture. Thus the selective advantages of loud, rapid mating calls in anurans are balanced by an increased risk of predation.     

Laughing gull chicks: recognition of their parents' voices

Laughing gull chicks between 6 and 13 days old responded to the calls of their own parents with orientation toward the sound, approach, increased locomotion, and vocalization. In response to the same kinds of calls from other adults they tended to orient away from the sound, withdraw, and sit or crouch. Chicks as young as 6 days can identify their parents from individual characteristics in the calls of adult gulls.     

Encoding of geographic dialects in the auditory system of the cricket frog

The frequency sensitivity of the auditory nervous system of cricket frogs (Acris) varies geographically. This variation is closely matched to the spectral energy in their mating calls, thus enabling them to respond preferentially to the calls of their local dialect.     

Enhanced distress vocalization through selective reinforcement

Eighteen Peking ducklings were imprinted and tested for their tendency to emit distress calls during the presentation and withdrawal of the imprinted stimulus. A subsequent arrangement in which each distress vocalization led to a 5-second presentation of the imprinted stimulus resulted in an enhanced tendency to emit distress calls.     

Signal perception in frogs and bats and the evolution of mating signals

Psychophysics measures the relationship between a stimulus's physical magnitude and its perceived magnitude. Because decisions are based on perception of stimuli, this relationship is critical to understanding decision-making. We tested whether psychophysical laws explain how female túngara frogs (Physalaemus pustulosus) and frog-eating bats (Trachops cirrhosus) compare male frog calls, and how this imposes selection on call evolution. Although both frogs and bats prefer more elaborate calls, they are less selective as call elaboration increases, because preference is based on stimulus ratios. Thus, as call elaboration increases, both relative attractiveness and relative predation risk decrease because of how receivers perceive and compare stimuli. Our data show that female cognition can limit the evolution of sexual signal elaboration.     

《呼啸山庄》中象征化描写的文化解读

《呼啸山庄》中运用了大量象征化的描写手法,艾米莉把自己在生活中所体悟到的深刻而又难以言传的人生哲理,通过意象的塑造,曲折地表现出来,为读者留下了无穷的想象空间,要求读者去积极地思考、探寻小说背后那丰富的象外之象、言外之意。     

From yield history to productivity zone identification with hidden Markov random fields

Modern precision agriculture equipment enables site-specific management by allowing different treatments for different parts of a field. This ability to subdivide the field calls for identifying management zones. A compromise between treating a field uniformly and treating every plant individually is needed, as the former does not maximize yields and the latter is often impractical. This work presents an algorithm for inferring the yield productivity zones (YPZ) for a field based on yield data from multiple years. The algorithm uses a hidden Markov random field model (HMRF) to find regions of the field which likely correspond to the same underlying yield distribution (i.e., productivity zones). These regions are modeled to be the same every year, but their distributions (i.e., yield characteristics) are allowed to vary with time to account for year-to-year variability (from e.g., weather effects, differing crops or crop varieties). The zone assignments and distributions are estimated using stochastic expectation maximization (SEM) and the maximizer of the posterior marginals (MPM). The underlying assumption of the model and algorithm is that the yields corresponding to a given YPZ will behave similarly and therefore derive from the same probability distribution. YPZs are useful inputs for determining management zones. An advantage of this method is that it is able to run with only the yield data which are automatically collected during harvest. Also, this method requires no crop specific calibration or configuration or normalization of the data by year.

     

Enhancement of symbioses between butterfly caterpillars and ants by vibrational communication

Butterfly caterpillars produce calls that appear to play a role in maintaining symbiotic associations with ants. A survey of butterfly species from South and Central America, North America, Europe, Thailand, and Australia suggests that the ability for caterpillars to call has evolved independently at least three times, and that calling may be ubiquitous among ant-associated species. Because ants use substrate-borne sound in their communication systems, this study points to the possibility that the calls of one insect species have evolved to attract other, unrelated species.