Female Calls Research Articles

Disruption of mating in codling moth (Lepidoptera: Tortricidae) by chlorantranilipole, an anthranilic diamide insecticide

The influence of the anthranilic diamide insecticide chlorantranilipole (DPX-E2Y45; Rynaxypyr against the adult stage of codling moth, Cydia pomonella L., was examined. Insecticide residues in plastic cups sprayed with 56 mg AI L(-1) (equivalent to the recommended field rate) had a minimal effect on adult survival or fecundity, but significantly fewer female moths were mated in treated than in untreated cups. Similar results were found in field studies with adults placed in screened cages on treated apple foliage for up to 3 weeks. Mating was disrupted when either sex was topically dosed with technical material (0.01-0.1 microg). Males were more sensitive to the disruptive effects of chlorantranilipole than females. A 2 h exposure significantly reduced male activity (walking and wing fanning), but not female calling. A 25 h exposure significantly reduced the activity of both sexes. The proportion of males landing near a sex pheromone source in a flight tunnel was significantly reduced following exposures of 2-4 h and completely eliminated following a 17 h exposure. Male moths partially recovered from either topical or residual exposure to chlorantranilipole, but the extent of their recovery was dose and time dependent. Male response to sex pheromone recovered within 2 h following a 4 h exposure, but following a 17 h exposure only a partial recovery occurred after 48 h. Mating by moth pairs exposed to chlorantranilipole residues for 24 h did not significantly increase during recovery periods of 24-96 h, except in cups treated with 10% of the standard concentration. The proportion of field-collected female codling moths caught in pear ester-baited traps that were mated was significantly lower in apple orchards treated season-long with chlorantranilipole compared with females caught in either untreated orchards or those treated with sex pheromones to cause mating disruption.

The importance of visual cues for nocturnal species: eagle owls signal by badge brightness

Nocturnal species may communicate by visual signals more frequently than previously thought. In fact, such species are habitually active around sunset and sunrise, when light conditions are still suitable for visual communication. We investigated the communication function of a visual cue in the eagle owl Bubo bubo, a nocturnal predator. In this species, territorial and courtship displays peak during the sunset and sunrise periods and involve the display of a white badge located on the throat whose reflectance properties are sex and period dependent. Experimental intrusions were conducted at 30 eagle owl territories in order to understand the function of the white badge during contests. We analyzed the reactions of both male and female owners toward a taxidermic mount with a normal brightness and a brightness-reduced white badge, with both male and female territorial calls. Our results indicate that the white badge of eagle owls plays an important role in visual communication during contests. Males displayed more frequently toward male low-brightness mounts, which were also approached more closely or attacked. Female behavior did not differ between experimental groups. Furthermore, a positive relationship between male badge brightness and breeding output suggested a potential role of the white badge as an honest signal of male quality. The need to convey information by visual communication in a nocturnal species may have promoted the evolution of visual signals employed at crepuscule. Copyright 2007.

Cockroach tergal glands producing female sex attractant pheromones and male aphrodisiacs in particular in the subfamily Blaberinae (Blattaria: Blaberidae)

Two principal pheromones are essential in all cockroach sexual behavioral sequences: the volatile sex attractant pheromone released by one partner for long distance attraction and an aphrodisiac sex pheromone produced exclusively by male tergal glands for female mounting and feeding behavior. In the Blaberinae subfamily, the female produces volatile sex attractant pheromones and the male, aphrodisiacs. A close relationship is known to exist between the release of these pheromonal signals from specific glands and the corresponding behaviors (female calling posture and male wing raising). However, in this cockroach group, no data on the glands secreting sex attractant pheromones and aphrodisiacs have been available until now. In seven species of the Blaberinae subfamily: Blaberus colosseus, B. craniifer, B. discoidalis, Blaptica interior, Byrsotria fumigata, Eublaberus distanti and E. posticus; one species of the Zetoborinae subfamily: Schultesia lampyridiformis; one species of the Epilamprinae subfamily: Epilampra maya and one species of the Panesthiinae subfamily, Panesthia sp., the females possess all pygidial glands on the 10 th tergite and the males have tergal glands situated anteriorly, generally on tergites T1 and T2. These glands are formed of type 3 glandular units with two cells, i.e. glandular and canal cells. The uniform presence of female pygidial glands and male tergal glands explains their relationship with their corresponding sexual behaviors.

Vocal development in captive harbor seal pups,Phoca vitulina richardii: Age, sex, and individual differences

The goal of this research was to determine when harbor seal pup vocalizations become sufficiently distinctive to allow individual recognition. A total of 4593 calls were analyzed from 15 captive pups. Nineteen were harsh, broadband, staccato calls used in an aggressive context. The rest were tonal "mother attraction calls," having an inverted "v"- or "u"-shaped spectrogram with harmonics and a fundamental frequency around 200-600 Hz. Calls were individually distinctive even in pups less than 2 weeks old, suggesting that mothers may be able to recognize pup vocalizations at this early age. Classification rates from discriminant function analysis were generally comparable to those of other phocids and less than in otariids, supporting the theory that recognition is more highly developed in otariids. Significant differences were found between male and female pup calls, and there were significant interactions between pup sex and age. The results of this study should be interpreted with caution until the findings are verified in wild harbor seal pups.

Mother‐Young Recognition in an Ungulate Hider Species: A Unidirectional Process

Parent-offspring recognition is usually crucial for survival of young. In mammals, olfaction often only permits identification at short range, and vocalizations are important at longer distances. Following and hiding antipredator strategies found in newborn mammals may also affect parental recognition mechanisms. We investigated mother-offspring recognition in fallow deer, an ungulate hider species. We analyzed the structure of adult female and fawn contact calls to determine whether they are individually distinctive and tested for mother-offspring recognition. Only females (and not fawns) have individualized vocalizations, with the fundamental frequency as the most distinctive parameter. Playback experiments showed that fawns can distinguish the calls of their mothers from those of other females, but mothers could not discriminate their own and alien fawn calls. Thus, the vocal identification process is unidirectional. In followers, mother-offspring acoustic recognition is mutual, and therefore the different antipredator strategies of newborn mammals may have shaped the modalities of parent-offspring acoustic recognition.

Antennal and Behavioral Responses of Virgin and Mated Oriental Fruit Moth (Lepidoptera: Tortricidae) Females to Their Sex Pheromone

Abstract Electroantennogram (EAG) and behavioral responses of female oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), were studied using the synthetic major component, (Z)-8-dodecenyl acetate, and partial three-component blend, (Z)-8-dodecenyl-acetate:(E)-8-dodecenyl-acetate:(Z)-8-dodecenol (in a 93:6:1 ratio), of the sex pheromone. EAGs elicited by both the single and three-component pheromone were significantly greater compared with hexane solvent controls. In 1-liter plastic chambers with constant throughput of air (50 ml/min) over rubber septa loaded with 0.01 or 0.1 mg of the three-component pheromone blend, onset of female calling was advanced by ≈2 h compared with solvent controls. However, the total number of females calling at peak time and the time of calling termination did not differ between pheromone-exposed and control moths. Oviposition rates of pheromone-exposed and clean air-exposed mated female moths did not differ in similar 1-liter flow-through chambers lined...

Mate Preference and Mating Behavior of Male <I>Helicoverpa zea</I> (Lepidoptera: Noctuidae) Infected with the Sexually Transmitted Insect Virus Hz-2V

The affect of Hz-2V (a.k.a. gonad-specific virus) virus infection on the reproductive physiology and behavior of infected adult Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) males was examined. Virus-infected males responded and flew to calling healthy and infected females at about the same rate. Although infected males were slower in approaching healthy females and attempting to mate compared with healthy males, infected males did make sexual contacts with females that could serve to transmit virus. Unlike matings with healthy males, which result in the cessation of calling, females that had made sexual contact with infected males continued to exhibit calling behavior and were receptive to mates. Although calling behavior of both healthy and infected females was inhibited by injecting extracts of reproductive tissues from healthy males, extracts of reproductive tissues from infected males inhibited female calling to a lesser degree and for an additional night compared with extracts from healthy males. The results presented here further demonstrate the ability of Hz-2V to alter the physiology and behavior of infected insects in ways that could serve to facilitate virus transmission.

Heterosexual and homosexual behaviour and vocalisations in captive female koalas ( Phascolarctos cinereus)

Female koalas ( Phascolarctos cinereus) exhibit both homosexual and heterosexual interactions in captivity, even though only heterosexual copulations have been observed in the wild. A key component of sexual interaction is the acoustic bellow, which is produced by males in the wild and both females and males in captivity. We recorded events in both homosexual and heterosexual interactions in a captive koala population, and vocalisations during and outside these interactions. A total of 43 homosexual and 15 heterosexual interactions were recorded in female koalas and were found to have the same principle components following presentation of the mounting male or female to the female: a short delay from neckbite to thrusting, a thrusting phase, followed by a pause and finally jerking behaviour. Thrusting and jerking phases were longest and were of approximately equal length. The delay from neckbite to thrusting, the thrusting phase and the jerking phase were shorter in homosexual than heterosexual mountings, which may relate to the absence of penile intromission and ejaculation. Female koalas exhibited characteristic oestrous and rejection vocalisations that may attract partners or result in them being rejected. The female post-mating calls and calls outside oestrus were longest, followed by female oestrous bellows and male calls, with female rejection calls being the shortest. Rejection calls were higher frequency than the oestrous calls, in particular rejection of a female. Following separation of bellow acoustics into a grunt and a shorter inhalation component, female bellows could be successfully discriminated from male bellows for 64% of the grunt phases, and 71% of the inhalation phases ( P < 0.001). Most of the variation between individuals was in the duration, rather than the harmonic range, starting or mean frequency, which were similar for both homosexual and heterosexual copulations. It is concluded that homosexual and heterosexual interactions in female koalas contain the same behavioural components, and similar accompanying vocalisations, although the duration of the different components is specific to the gender and stage of copulation.

Diel Periodicity of Emergence and Premating Reproductive Behaviors of Adult Dogwood Borer (Lepidoptera: Sesiidae)

The emergence and premating reproductive behaviors of adult dogwood borer moths, Synanthedon scitula Harris (Lepidoptera: Sesiidae), were examined under controlled conditions in the laboratory and in apple orchards in Virginia. The diel periodicity of male response to pheromone sources was recorded using traps baited with commercial pheromone lures and with a recently identified, trinary blend of dogwood borer sex pheromone components. An earlier study reporting a significant effect of pheromone trap height on the capture of male dogwood borer was revisited, using commercial lures and the new pheromone. Under a 16:8 (L:D)-h photo regimen, the emergence of male and female moths showed a diel periodicity, peaking at 0600 hours. Sexual receptivity of female moths, indicated by the onset of calling behavior, occurred in most individuals on the day after emergence and was observed only during the crepuscular period just before and after sunset. Similarly, the capture of male dogwood borer in traps deployed in July and baited with virgin female moths or pheromone lures coincided with the period of female calling behavior, peaking sharply between 2000 and 2100 hours. When pheromone-baited traps were deployed in September, the peak capture of male dogwood borer occurred earlier, between 1900 and 2000 hours. Traps baited with a commercial lure captured significantly more male dogwood borer at 1.8 m (6 ft), whereas those baited with the trinary dogwood borer sex pheromone captured similar numbers of males at elevations ranging from 1.2 to 2.4 m (4–8 ft). Use of the new dogwood borer sex pheromone has tremendously increased the precision of trapping data and has yielded reliable measurements of the behavior and abundance of male moths that pertain directly to improved monitoring and management capabilities.

Divergence in female calling song discrimination between sympatric and allopatric populations of the southern wood cricket Gryllus fultoni (Orthoptera: Gryllidae)

Two species of closely related wood cricket, Gryllus fultoni (Orthoptera: Gryllidae) and Gryllus vernalis, occur together in some parts of the eastern United States and have a similar calling song structure, consisting of three-pulse chirps. A previous study revealed that chirp rate in G. fultoni was highest (greatest difference vis-a-vis chirp rate in G. vernalis) in sympatric populations, intermediate in near allopatric populations that were located close to the sympatric zone, and lowest in allopatric populations. A similar trend was observed in pulse rate, but the mean values of this trait showed much more convergence than chirp rate at the low end of the range of calling temperatures. In this study, we investigated the song discrimination of females from sympatric and allopatric populations of G. fultoni at about 23°C, which is near the middle of the normal range of calling temperatures. We used both single-stimulus and two-stimulus playback experiments to learn if geographical differences in song preferences paralleled those in calling songs. Stimuli presented were representative of calling songs in three classes of G. fultoni populations (sympatric, near allopatric, and far allopatric), a calling song of G. vernalis, and three calling songs with parameter values that were intermediate with respect to those of the songs of far allopatric G. fultoni and G. vernalis. In the single-stimulus playbacks, females of all G. fultoni populations responded poorly if at all to the heterospecific stimulus. Females of sympatric and near allopatric populations responded poorly to all intermediate stimuli, but females of far allopatric populations frequently responded to these sounds. In the two-stimulus playbacks, females of sympatric and near allopatric populations generally discriminated against intermediate and heterospecific stimuli. However, females of far allopatric populations often did not discriminate against intermediate stimuli, whose characteristics resembled the calling songs of G. vernalis. The divergent pattern of female phonotactic discrimination between sympatric and far allopatric populations was thus generally congruent with the pattern of divergence in chirp and pulse rates and would be expected to significantly reduce heterospecific mating in sympatry. These geographical patterns of female song discrimination and male calling songs conform to a commonly used definition of reproductive character displacement.

MALE AND FEMALE STRIDULATION IN AN INDIAN WETA (ORTHOPTERA: ANOSTOSTOMATIDAE)

ABSTRACT We present the first description of the calls and stridulatory structures of males and females of an Indian weta species from the Western Ghats of Southern India. Calls of males and females produced by femoro-abdominal stridulation were recorded and call features such as chirp duration, chirp period, syllable period and syllable duration were characterised. The calls of males were highly stereotyped with regular chirp periods and durations whereas chirp rates in the female calls were more variable. The number of syllables per chirp was constant for males and females and the fine temporal features such as syllable periods and syllable durations showed low inter-individual variation in both males and females. The arrangement of femoral stridulatory structures was different from the previously described anostostomatid species. The high stereotypy of calls of males and females indicates that the signal could serve for identification of species and sex.

Pheromone Release Behaviour in Females of Phyllonorycter junoniella (Z.) (Lepidoptera, Gracillariidae) Under Constant and Cycling Temperatures

The calling activity of virgin Phyllonorycter junoniella (Z.) females under a cycling thermal regime differed from that under constant temperature in the following ways: the percentage of females calling at the morning activity peak was increased; the morning period of calling activity was prolonged; the total period of calling activity of an individual female was increased; an extra peak of activity occurred at the end of the photophase, and females changed the calling pattern during the active period. We assume that the occurrence of two calling peaks and the extension of the calling period might be adaptive for a Ph. junoniella species with a sex ratio strongly shifted towards females (8:1 females:males), as it could lead to an increased proportion of females mated.

The evolution of female copulation calls in primates: a review and a new model

Female copulation calls are mating-associated vocalizations that occur in some species of Old World monkeys and apes. We argue that copulation calls have two immediate functions: to encourage mating attempts by other males and to increase mate guarding by the consort male. We hypothesize that female copulation calls have evolved under the selective pressures of risk of infanticide and sperm competition. When male mate guarding is effective, copulation calls allow females to concentrate paternity in dominant males and benefit from their protection against the risk of infanticide. When mate guarding is ineffective, copulation calls may bring genetic benefits to females through facilitation of sperm competition. We present a quantitative model in which interspecific variation in females' promiscuity predicts their tendency to use copulation calls in conjunction with mating. The model predicts that in species with little female promiscuity, copulation calls should be rare and exhibited only in association with mating with dominant males. In species in which females are highly promiscuous, copulation calls should be frequent and unrelated to male dominance rank. The limited data available to test the model support its main predictions as well as the predicted relation between copulation calls and male dominance rank.

Functional morphology of Richardson's ground squirrel, Spermophilus richardsonii, alarm calls: the meaning of chirps, whistles and chucks

Repetitive alarm vocalizations of Richardson's ground squirrels vary in terms of the acoustic structure of their primary syllables and the inclusion of brief, lower-amplitude, frequency-modulated trailing elements we term ‘chucks.’ Chucks are included in calls of both males and females and increase in prevalence with the proximity of the caller to the alarm-evoking stimulus. Furthermore, chuck presence is not independent of primary syllable type: chucks follow primary syllables that have constant frequency and diminishing amplitude (‘whistle’), but do not trail primary syllables with diminishing frequency and nondescending amplitude spectra (‘chirps’). Playbacks to free-living squirrels of repeated alarm calls having whistle- or chirp-like primary syllables factorially combined with chuck presence or absence revealed that chirp-like syllables elicited greater vigilance from call recipients during signal propagation. The addition of chucks to the end of primary syllables of either type, however, increased initial vigilance duration and the proportion of time devoted to vigilance during and after signal reception. Chucks thus promote increased and lasting vigilance on the part of call recipients. Beyond enhancing vigilance, however, the inclusion of frequency-modulated chucks and chirps facilitates the orientation of receivers to the signaller. Multiple acoustic parameters of Richardson's ground squirrel alarm vocalizations thus interact to communicate information regarding several aspects of a predator encounter. Receivers use this information to their advantage, affording greater attention to calls that would be more readily located by predators, and hence are more costly for signallers to produce.

Female Copulation Calls in Guinea Baboons: Evidence for Postcopulatory Female Choice?

We tested the hypothesis that primate female copulation calls are a form of postcopulatory female choice. We collected data on female sexual swellings, sexual and agonistic behavior, copulation calls and postcopulatory behavioral interactions in a multimale-multifemale captive group of Guinea baboons over a 3-mo period. Males copulated with only a few females, and females copulated with only 1 or 2 different males in the group, suggesting a harem-like mating system similar to that of hamadryas and gelada baboons. Female copulations were most likely to occur at peak sexual swellings and male copulatory success was accounted for by dominance rank and age. Variation in female tendencies to call after copulation is best explained by the copulatory success of the male with which each female copulated the most and by the number of copulating partners. The findings are consistent with predictions that calls are likely to be associated with copulation with preferred males and the risk of sperm competition. The prediction that copulation calls increased the probability of postcopulatory mate guarding is also supported. Taken together, the findings suggest that female copulation calls may play an important role in postcopulatory sexual selection and in particular in the expression of postcopulatory female choice in primate species in which females have little opportunity to choose their mates or female mate choice is costly or both.

Social context modulates behavioural and brain immediate early gene responses to sound in male songbird

Although it is well known that brain sensory information processing is a highly modulated phenomenon, how this brain function is shaped by experience and social context remains a question to explore. In this paper, we present the first attempt to investigate this problem using a songbird acoustic communication paradigm. Social context is well known to influence acoustic communicating behaviours in birds. The present paper investigates whether brain processing of auditory inputs can be modulated by this 'audience effect'. Given that call-based communication is known to be highly context-dependent, we focused on the response of male zebra finches (Taeniopygia guttata) to female calls. We tested to see if the current social context surrounding the hearing bird can modify a sound-induced immediate early gene (IEG) activation in the specific region of the caudomedial nidopallium (NCM), a songbird brain analogous to the superficial layers of the mammalian primary auditory cortex. Our results show that the expression of the sound-induced immediate early gene ZENK in the NCM is considerably enhanced when the hearing bird is in the presence of conspecifics, compared to when he is alone. This context-dependent increase of a sound-induced immediate early gene expression can be correlated with the differential behavioural response of males to the playback of the same acoustic stimulus as a function of social context.

Development of vocalizations in the flat-headed bats, Tylonycteris pachypus and T. robustula (Chiroptera: Vespertilionidae)

The development of vocalizations during postnatal growth in the flat-headed bats, Tylonycteris pachypus and T. robustula in South China is described. Females of both species gave birth to twins at the end of May, and the infants flew in the last ten days of June. Vocalizations served as precursors to echolocation calls and as isolation calls (i-calls) used to attract mothers. As the infants grew, the frequency of i-calls and precursor calls increased. The duration of i-calls increased little before 6-day old and then decreased. At the same time, the duration of echolocation precursor calls decreased. The directive calls that the mother or the infant emitted when searching for each other are also described. Female directive calls are lower in frequency and longer in duration than their echolocation calls, and the duration of infant directive calls is longer than those of the i-calls and precursor calls.

Vibratory signals of four Neotropical stink bug species

Abstract. The stink bugs Acrosternum impicticorne, Euschistus heros, Piezodorus guildinii and Thyanta perditor (Heteroptera: Pentatomidae) feed and mate on the same host plants and constitute major components of the soybean pest complex in Brazil. During mating, they communicate with species and sex‐specific vibratory signals whose spectral properties are characteristic of the subfamily Pentatominae. Songs differ between species in the time structure and amplitude modulation of their units. The repertoire of A. impicticorne, E. heros and T. perditor fits into the scheme described for most investigated stink bugs: females call with a sequence of pulses that differ between species in their duration and repetition rate, and males respond with courtship songs of species‐specific temporal structure and amplitude modulation of complex pulse trains. Female calling and male courtship songs are the main constituents of vibratory communication between sexes in the mating period. The other vibratory emissions appear to represent either transitional songs, support recognition during close‐range courtship, or are involved in male rivalry. The first recorded vibratory emissions of P. guildinii confirm that the genus Piezodorus represents an exception within the Pentatominae. Irregularly repeated female vibratory signals of P. guildinii do not trigger typical male courtship responses as they would in the small stink bugs Holcostethus strictus and Murgantia histrionica. On the other hand, complex rivalry with extensive frequency modulation of pulses, as also described in Piezodorus lituratus, opens a new insight into the role of vibratory communication in stink bugs.

Mating behaviour in a slave-making ant, Rossomyrmex minuchae (Hymenoptera, Formicidae)

The mating behaviour of the ant Rossomyrmex minuchae, a rare, protected slave-making species in Spain, seems to be significantly affected by its particular life history and patchy habitat. The mating behaviour of the entire genus Rossomyrmex is virtually unknown. We present here the results of a 3-year study of mating behaviour in R. minuchae.Behavioural observations and limited nest excavations revealed that R. minuchae does not produce sexuals every year, the number of sexuals is low, and the sex ratio tends to be female biased. Females typically exhibit two distinct activity periods. The first, the mating period, takes place in early afternoon: the ants "call" near the natal nest, mate and then return to their nest. The second, the dispersal period takes place in late afternoon: the mated females exit their nest and fly in search of a new, non-parasitized Proformica longiseta host nest. Males are highly active during the mating period, but will remain inactive in the dispersal period even if experimentally presented with virgin females. It appears that females are monogamous, while males are polygamous. When males are late arriving at the female calling site, the females will frequently congregate presumably calling in chorus. The low reproductive efficiency exhibited by R. minuchae, coupled with the postulated low genetic variation in the population, as sisters may mate with the same male, could result in a low survival rate and risk of eventual extinction. The observed decrease in nest density we observed during the 2004 season may be indicative of such a process.

Sharing Clinical Decisions by Discussing Evidence with Patients

Our patients receive skillfully presented medical information from multiple sources other than us—in particular, from direct-to-consumer pharmaceutical advertising that pervades television, radio, print media, and the Internet. At the same time, clinicians cannot easily keep pace with the volume of new medical information available from studies—and the quality of studies may vary greatly. We clinicians must therefore differentiate high-quality from less-than-high-quality evidence and become skilled in communicating this difference to patients to help address their concerns. Consider the following scenario: A 55-year-old thin, nonsmoking female calls you with questions about her hormone therapy. Two months ago, she started a regimen of estrogen 0.625 mg and progesterone 2.5 mg daily to treat perimenopausal hot flushes. She has no history of hypertension but has impaired glucose tolerance with a fasting blood glucose level of 114 mg/dL. Her total cholesterol level is 185 mg/dL; low-density lipoprotein (LDL) cholesterol level, 120 mg/dL; high-density lipoprotein (HDL) level, 45 mg/dL; and triglyceride level, 100 mg/dL. Her mother has coronary artery disease, which manifested at age 60 years. The patient has had excellent relief of her hot flushes. She recently read an article (in a lay publication) that warned all women to stop hormone therapy, but she is concerned that symptoms might recur if she does this. What should you tell her? Shared decision making is an excellent approach for discussing treatment options with patients like the one described here. Shared decision making is a communication strategy that provides evidence to patients in a nonbiased way and that shares with patients the basis as well as the responsibility for making medical decisions. Moreover, this approach inherently recognizes and respects patient's values; helps patients to consider the seriousness of the condition to be prevented or treated; helps patients to understand risks, benefits, and alternative options for diagnosis and treatment; engages patients in the decision-making process at a level which they personally find comfortable and desirable; and includes patients' own beliefs and values as factors in the decision-making process.1 In this sense, shared decision making differs from the process of obtaining informed consent; in that process, risks and benefits are disclosed without explicitly incorporating the patient's values or sharing the basis for decision making in a formal decision-making process. Shared decision making should not be used to intentionally steer patients to a particular decision. According to one study, 19% to 68% of patients—especially younger, more highly educated patients—are interested in sharing the decision-making process with their physicians.2 Shared decision making is consistent with the Institute of Medicine's call for a patient-provider partnership “to ensure that decisions respect patients' wants, needs, and preferences and that patients have the education and support they require to make decisions and [to] participate in their own care.”3:p7 Further, shared decision making may promote trust within patient-physician relationships, enhance patients' confidence about participating in their own health care, and reduce patients' decisional conflict with a chosen course of care. In general, strategies for shared decision making are applicable in four situations: When recommendations conflict with one another or insufficient evidence exists to form a basis for recommending for or against an intervention When several possible interventions are believed to have approximately equal effectiveness When the benefits of an intervention may vary from patient to patient When, on the basis of their values or personal situation, patients may differ in the way they weigh the risks and benefits of an intervention.