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.     

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.     

Mate Selection and Behavioral Thermoregulation in Fowler's Toads

Male Fowler's toads produce mating calls that are affected by the body size and temperature of the caller. Females are able to discriminate between variations in these calls and select the largest available males. By thermoregulation, males are able to alter their calls to make them more attractive to females.     

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.     

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.     

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.     

Temperature Coupling in the Vocal Communication System of the Gray Tree Frog, Hyla versicolor

The gray tree frog mates over a temperature range of at least 9 degrees C. Gravid females, tested at two different temperatures, preferred synthetic mating calls with temperature-dependent temporal properties similar to those produced by a male at about the same temperature as their own. Thus, the vocalization system and the temporal pattern recognition system are affected by temperature in a qualitatively similar fashion.     

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.     

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.     

Deficit in attachment behavior in mice lacking the mu-opioid receptor gene

Endogenous opioid binding to micro receptors is hypothesized to mediate natural rewards and has been proposed to be the basis of infant attachment behavior. Here, we report that micro-opioid receptor knockout mouse pups emit fewer ultrasonic vocalizations when removed from their mothers but not when exposed to cold or male mice odors. Moreover these knockout pups do not show a preference toward their mothers' cues and do not show ultrasonic calls potentiation after brief maternal exposure. Results from this study may indicate a molecular mechanism for diseases characterized by deficits in attachment behavior, such as autism or reactive attachment disorder.     

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。     

基于网络环境的图书馆自动化建设刍议——以党校系统图书馆为例

党校教育的发展,迫切需要把传统型的图书馆尽快建设成为自动化、数字化、网络化的文献信息中心。文章提出了若干构想。     

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.     

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.     

Vocalization evoked from the optic lobe of a songbird

Vocalizations from songbirds have been evoked by electrical stimulation of the torus. These vocalizations resemble the normal alarm and scolding calls of the species. The torus of the birds appears to correspond functionally and anatomically to the mammalian central gray matter.     

Whistle matching in wild bottlenose dolphins (Tursiops truncatus)

Dolphin communication is suspected to be complex, on the basis of their call repertoires, cognitive abilities, and ability to modify signals through vocal learning. Because of the difficulties involved in observing and recording individual cetaceans, very little is known about how they use their calls. This report shows that wild, unrestrained bottlenose dolphins use their learned whistles in matching interactions, in which an individual responds to a whistle of a conspecific by emitting the same whistle type. Vocal matching occurred over distances of up to 580 meters and is indicative of animals addressing each other individually.     

Honeyguides and honey gatherers: interspecific communication in a symbiotic relationship

In many parts of Africa, people searching for honey are led to bees' nests by the greater honeyguide (Indicator indicator Sparrman). The Boran people of Kenya claim that they can deduce the direction and the distance to the nest as well as their own arrival at the nest from the bird's flight pattern, perching height, and calls. Analyses of the behavior of guiding birds confirmed these claims.     

A common variant on chromosome 9p21 affects the risk of myocardial infarction

The global endemic of cardiovascular diseases calls for improved risk assessment and treatment. Here, we describe an association between myocardial infarction (MI) and a common sequence variant on chromosome 9p21. This study included a total of 4587 cases and 12,767 controls. The identified variant, adjacent to the tumor suppressor genes CDKN2A and CDKN2B, was associated with the disease with high significance. Approximately 21% of individuals in the population are homozygous for this variant, and their estimated risk of suffering myocardial infarction is 1.64 times as great as that of noncarriers. The corresponding risk is 2.02 times as great for early-onset cases. The population attributable risk is 21% for MI in general and 31% for early-onset cases.     

ESSAYS ON SCIENCE AND SOCIETY: Privatizing the University--the New Tragedy of the Commons

Teaching and research at universities is increasingly funded from private sources. In this essay, Brown highlights the problems associated with this approach and calls for a return to largely public funding. He argues that the public, rather than corporations or individual scientists or even secretive governments, should own the results.     

论高校学生信息素养的培养

信息时代呼唤信息素养,尤其是处于转折点的大学生。从信息素养的积极意义出发,分析了信息素养培养的三个阶段,并从这三阶段论述信息素养培养的具体途径。