Honest Signal Research Articles

Initial employability development: introducing a conceptual model integrating signalling and social exchange mechanisms

ABSTRACT This article develops a conceptual understanding of initial employability development, specifically the transition into first career destinations. Substantial previous research focuses on the role of individuals in ensuring employment readiness and continued employability development. Studies also identify the importance of employers for sustained employability. However, the interdependence and interaction between employers and individuals are under-theorized. We integrate social exchange theory and signalling theory to conceptualize initial employability development. We propose a cyclical model that comprises interactive and reciprocal signalling and social exchange processes between employers and individuals. The model overcomes the limitations of linear conceptualizations and one-sided models that theorize employability as either the outcome of human capital resources deployed by individuals or as managed by employers in employability development processes. We extend the processual approach to employability by redirecting theoretical attention to the interaction of signalling and social exchange as fundamental to employability development. We conclude by discussing implications in relation to employability research and theory development.

Behavioural evolution of Neotropical social wasps (Vespidae: Polistinae): the queen selection process.

All Epiponini wasps are polygynic, with multiple queens alternating over the colony cycle. There are several potential queens in the early stages of this cycle, but as it progresses, the number of queens is reduced. Because most individuals remain reproductively totipotent, there is great potential for conflicts over reproduction. Workers could have an advantage in controlling queen production because they are much more numerous than queens. Nevertheless, the queen selection process is little known for Epiponini. For this reason, we aimed to study the behaviour of queens and workers during queen selection in multiple species of Epiponini, integrate information from previous behavioural studies, and perform a comparative analysis to interpret changes evolutionarily. We conducted observations on nine species belonging to five genera: Brachygastra, Chartergellus, Metapolybia, Polybia and Protopolybia. Females were individually marked to make direct and video observations. Queen production was artificially induced. A total of 28 behaviours related to queen selection were identified. The most aggressive interactions between castes, such as bite and dart, were lost in the major lineages of Epiponini. Bending display I is an ancient behaviour used as the main dominance display. Behaviours exhibited by workers to test queen status arose in the common ancestor of the Epiponini and are not shared by other polistine wasps. Consequently, the act of workers testing queen status probably was present in the Epiponini ancestor. Ritualized test display and dominance behaviours are used in Epiponini as honest signals of the queen's reproductive potential instead of aggressive behaviours. Caste flexibility had already been suggested as the ground plan for Epiponini and is herein discussed as decisive for colony survival of swarm wasps, because it allows colonies to respond efficiently to different situations that may eventually arise.

Acoustic properties of chimpanzee pant-hoots reflect male mate quality

Sexual selection theory predicts that acoustic structure may provide cues of individual traits correlated with mate quality. Chimpanzee pant-hoots are complex, conspicuous calls that may be products of sexual selection. Insofar as pant-hoots are difficult to produce, requiring individuals to approach their physiological limits of sound production, they may serve as honest signals of physical condition. The highest pitch elements in pant-hoots appear the most difficult elements to produce, as they sometimes exhibit distortions in acoustic structure known as non-linear phenomena (NLP). Producing high pitch vocalizations with fewer NLPs may, thus, signal superior physical condition. We examined whether the proportion of NLPs, the pitch, and noise in these elements of the pant-hoots contain cues of mate quality including age, rank, and a measure of health (infection with the simian immunodeficiency virus, SIVcpz), and if they predict male mating success. Consistent with predictions from sexual selection, we found that (i) the proportion of NLPs was associated with age in a non-linear fashion—specifically, subadult and old males exhibited higher proportions of NLPs compared to males in their prime mating age; (ii) a lower proportion of NLPs predicted higher mating success; and (iii) SIVcpz positive individuals exhibited more noise in their pant-hoots.

Exposure to chlorpyrifos during pregnancy differentially affects social behavior and GABA signaling elements in an APOE- and sex-dependent manner in a transgenic mouse model

The massive use of chlorpyrifos (CPF) has been associated with an increased prevalence of neurodevelopmental disorders. Some previous studies have shown that prenatal, but not postnatal, CPF exposure causes social behavior deficits in mice depending on sex while others have found that in transgenic mice models carrying the human apolipoprotein E (APOE) ε3 and ε4 allele confer different vulnerabilities to either behavioral or metabolic disorders after CPF exposure. This study aims to evaluate, in both sexes, how prenatal CPF exposure and APOE genotype impact on social behavior and its relation to changes in GABAergic and glutamatergic systems. For this purpose, apoE3 and apoE4 transgenic mice were exposed through the diet to 0 or 1 mg/kg/day of CPF, between gestational day 12 and 18. A three-chamber test was used to assess social behavior on postnatal day (PND) 45. Then, mice were sacrificed, and hippocampal samples were analyzed to study the gene expression of GABAergic and glutamatergic elements. Results showed that prenatal exposure to CPF impaired social novelty preference and increased the expression of GABA-A α1 subunit in females of both genotypes. In addition, the expression of GAD1, the ionic cotransporter KCC2 and the GABA-A α2 and α5 subunits were increased in apoE3 mice, whereas CPF treatment only accentuated the expression of GAD1 and KCC2. Nevertheless, future research is needed to evaluate whether the influences detected in the GABAergic system are present and functionally relevant in adults and old mice.

Articulatory effects on perceptions of men’s status and attractiveness

Research on heterosexual mating has demonstrated that acoustic parameters (e.g., pitch) of men’s voices influence their attractiveness to women and appearance of status and formidability to other men. However, little is known about how men’s tendency to clearly articulate their speech influences these important social perceptions. In the current study, we used a repeated-measures design to investigate how men’s articulatory clarity or conformity influenced women’s (N = 45) evaluations of men’s attractiveness for both short- and long-term relationships, and men's (N = 46) evaluations of physical formidability and prestige. Results largely supported our hypotheses: men who enunciated phonemes more distinctly were more attractive to women for long-term relationships than short-term relationships and were perceived by other men to have higher prestige than physical dominance. These findings suggest that aspects of articulatory behavior that influence perceptions of prestige and long-term mating attractiveness may indicate an early social history characterized by high socioeconomic status, likely owing to crystallization of articulatory patterns during the critical period of language development. These articulatory patterns may also be honest signals of condition or disposition owing to the nature of complex, multicomponent traits, which deserve further empirical attention.

TCF7L2 acts as a molecular switch in midbrain to control mammal vocalization through its DNA binding domain but not transcription activation domain

Vocalization is an essential medium for social signaling in birds and mammals. Periaqueductal gray (PAG) a conserved midbrain structure is believed to be responsible for innate vocalizations, but its molecular regulation remains largely unknown. Here, through a mouse forward genetic screening we identified one of the key Wnt/β-catenin effectors TCF7L2/TCF4 controls ultrasonic vocalization (USV) production and syllable complexity during maternal deprivation and sexual encounter. Early developmental expression of TCF7L2 in PAG excitatory neurons is necessary for the complex trait, while TCF7L2 loss reduces neuronal gene expressions and synaptic transmission in PAG. TCF7L2-mediated vocal control is independent of its β-catenin-binding domain but dependent of its DNA binding ability. Patient mutations associated with developmental disorders, including autism spectrum disorders, disrupt the transcriptional repression effect of TCF7L2, while mice carrying those mutations display severe USV impairments. Therefore, we conclude that TCF7L2 orchestrates gene expression in midbrain to control vocal production through its DNA binding but not transcription activation domain.

Categorizing relative water use perception bias using household surveys and monthly water bills

We introduce the concept of relative water use perception bias to highlight the role of human relationships, social cues, and the built environment in household water consumption. Although previous studies have explored actual water use, it is also important to understand how people perceive their relative behaviors because humans are social animals and act in relation to each other. We combine household survey responses and water utility bills in a large sample of households to quantify the degree of over- and under-estimation bias in perceived relative household water use. We then use multi-level nested regression models to investigate four categories of potential influence: sociodemographic characteristics, perceived social norms, neighborhood characteristics, and water bill information. Results show that most households tended to view themselves as ‘better than average’ water users when they actually used more water compared to neighbors. Respondents in high-income households and those who are more concerned about water shortages were more likely to underestimate their relative water use (using comparatively more than they thought). However, in more suburbanized neighborhood environments, households were more likely to overestimate their relative water use (using comparatively less than they thought). We call the inaccuracy in assessing water usage compared to their neighbors' relative water use perception bias. We propose that a better understanding of this bias can aid the design of policy initiatives like neighborhood planning, better water bill design, targeted messaging, and social signaling. By bringing a relational lens to bear on water conservation studies, understanding relative water use perception bias sheds new light on the complex drivers of household water consumption.

Reduced reflectance and altered color: The potential cost of external particulate matter accumulation on urban Rock Pigeon (Columba livia) feathers

Feather quality in birds is considered an honest signal of individual health as feather appearance and function depend on an individual’s ability to maintain them. In addition to flight and insulation, feathers are essential for social interactions and sexual selection in the form of visual signals. Airborne particulate matter (PM) can accumulate on feather surfaces and alter feather appearance. We quantified PM accumulation on Rock Pigeon (Columba livia) feathers and analyzed the spectral properties of extracted particulates. Feathers were sampled from two pigeon populations, one rural and one urban, in the Dallas-Fort Worth area, with 47 and 93% developed land cover, respectively, within 2 km of the populations. We determined accumulated PM gravimetrically after rinsing feathers and then measured the visible-near-infrared diffuse reflectance and color properties of extracted particulates. The rate of PM accumulation on rural birds was higher than on urban birds. However, feather particulates collected from urban pigeons had significantly lower total reflectance, reflectance in the visible portion of the spectrum, lightness, and hue angle compared to those of rural pigeons. The hue angle of rural feather particulates displayed a negative relationship with PM accumulation while total reflectance, reflectance in the visible range, and lightness of urban feather particulates were negatively related to PM accumulation. Our findings suggest that wild birds could incur an urban pollution penalty as PM accumulation has the potential to alter feather properties. Further research is needed to better understand the influence of external PM accumulation on the physiological and behavioral health of birds.

Antecedents to the conspicuous consumption of luxury fashion brands by middle-income black South Africans

PurposeSouth Africa is increasingly becoming an attractive market for luxury fashion brands due to the growing middle-income consumer segment, which is perceived to be upwardly mobile. Despite evidence of black South African's exhibition of heightened interest in conspicuous consumption (CC), there seems to be limited research addressing the drivers and implications of such behaviour. This study aims to investigate the antecedents of CC by middle-income black South Africans and the marketing implications thereof.Design/methodology/approachThis study employed a survey questionnaire approach and a quantitative methodology for primary data collection. Data were gathered from a sample of 170 respondents across South Africa and analysed using structural equation modelling (SEM) through SPSS and Mplus software. Confirmatory factor analysis was used to test model fit, reliability and validity of measurement instruments, while path modelling was used to test hypotheses adopted by this report.FindingsAmong the major findings made by this report was that social class signalling positively influenced CC. In contrast, CC was not predicted by status consumption (SC). This study concluded that social factors motivated the CC of luxury fashion brands by middle-income black South Africans.Practical implicationsThis study's key recommendations were for marketing professionals to imbue overt status cues in their brand campaigns to drive the consumption of luxury fashion brands. Future studies could investigate whether or not the findings of this study are applicable across ethnic demographics in South Africa.Originality/valueThe study extends the discourse of the antecedents of ethnic consumer behavioural patterns in a historically segregated market. It weighs in on the growing research addressing factors driving the middle-income population from emerging economies to consume luxury fashion brands conspicuously.

Sounds of snapping shrimp (Alpheidae) as important input to the soundscape in the southeast China coastal sea

As a biological sound source widely distributed in temperate and tropical coastal waters, snapping shrimp produce strong pulses which can serve as honest signals to indicate habitat-specific soundscape. The past decade has witnessed the growing interest in investigating the acoustical activity of snapping shrimp across many shallow waters including the coastal line of the west Pacific Ocean. It was extended to the Southeast China coastal area where snapping sounds and the associated soundscape were recorded at four sites. Customized codes incorporating bandwidth and amplitude threshold operations were developed to detect snaps from the ambient noise to estimate snap rate and extract snaps individually. The subsequent analysis suggested that snaps recorded at different sites were unanimously stronger than background noise. Sound pressure level of the snaps ranged from 150 dB to 190 dB (re 1 μPa). The characteristics of snaps, including sound pressure level, duration, peak frequency, -3dB bandwidth from different sites are examined to evaluate the variability across the sites. Though snapping pulses had peak frequencies and the -3 dB bandwidth consistently below 10 kHz, snaps had considerable energy extending to the high frequency range over 200 kHz. The analysis of the acoustic data received for 7 consecutive days at one site indicated that the snap rate corresponded to tidal level periodicity. A high tide was accompanied with a local high snap rate regardless of light but this local snap rate peak was much higher at night. The mean rate fluctuated between 2000 and 4000 snaps per minute and more snaps were recorded after sunset suggesting that snapping shrimp living in the area snapped in response to light. These data may indicate that snaps are important communication means in light-limited condition and deepen our understanding on the correlation of snapping behavior and ecological environments.

The price of defence: toxins, visual signals and oxidative state in an aposematic butterfly.

In a variety of aposematic species, the conspicuousness of an individual's warning signal and the quantity of its chemical defence are positively correlated. This apparent honest signalling is predicted by resource competition models which assume that the production and maintenance of aposematic defences compete for access to antioxidant molecules that have dual functions as pigments and in protecting against oxidative damage. To test for such trade-offs, we raised monarch butterflies (Danaus plexippus) on different species of their milkweed host plants (Apocynaceae) that vary in quantities of cardenolides to test whether (i) the sequestration of cardenolides as a secondary defence is associated with costs in the form of oxidative lipid damage and reduced antioxidant defences; and (ii) lower oxidative state is associated with a reduced capacity to produce aposematic displays. In male monarchs conspicuousness was explained by an interaction between oxidative damage and sequestration: males with high levels of oxidative damage became less conspicuous with increased sequestration of cardenolides, whereas those with low oxidative damage became more conspicuous with increased levels of cardenolides. There was no significant effect of oxidative damage or concentration of sequestered cardenolides on female conspicuousness. Our results demonstrate a physiological linkage between the production of coloration and oxidative state, and differential costs of sequestration and signalling in monarch butterflies.

Explaining reward crowdfunding backers' intentions and behavior

PurposeEarlier research into crowdfunding adoption has drawn on social psychology, trust, signaling and well-being theories. Despite its wide appeal and use, the technology acceptance model (TAM) has received little attention in terms of explaining the adoption of crowdfunding platforms. The current study examines the applicability of two versions of this framework: the original TAM1 and the extended TAM2 frameworks.Design/methodology/approachData were collected through a survey distributed to the users of Finland's leading reward crowdfunding website, Mesenaatti, who have backed crowdfunding campaigns previously. The authors employed structural equation modelling (SEM–lavaan package) and conducted a series of quality tests to alleviate concerns with certain biases.FindingsAnalyses of 556 observations exhibit support for all hypotheses underlying both TAM frameworks, with two exceptions. Contrary to expectations, voluntariness does not moderate the effect of subjective norms on contribution intentions, and the effect of perceived ease-of-use is primarily mediated by perceived usefulness, rather than directly influencing intentions.Originality/valueFirst, the study extends the generalizability of TAM to the context of crowdfunding and with respect to financial contribution behavior. Second, it shows that backers' perceptions of platform usefulness and ease-of-use are important antecedents of crowdfunding contribution behavior, and that the former exerts greater influence than the latter. Third, it further clarifies the influences of relevant antecedents of crowdfunding backers' contribution intentions and behaviors. Specifically, the authors show that experience only weakly moderates the influence of subjective norms on contribution intentions, and voluntariness does not moderate this association. The authors discuss explanations for these findings and their implications for research and practice.

Long-wavelength-sensitive (lws) opsin gene expression, foraging and visual communication in coral reef fishes.

Coral reef fishes are diverse in ecology and behaviour and show remarkable colour variability. Investigating the visual pigment gene (opsin) expression in these fishes makes it possible to associate their visual genotype and phenotype (spectral sensitivities) to visual tasks, such as feeding strategy or conspecific detection. By studying all major damselfish clades (Pomacentridae) and representatives from five other coral reef fish families, we show that the long-wavelength-sensitive (lws) opsin is highly expressed in algivorous and less or not expressed in zooplanktivorous species. Lws is also upregulated in species with orange/red colours (reflectance >520 nm) and expression is highest in orange/red-coloured algivores. Visual models from the perspective of a typical damselfish indicate that sensitivity to longer wavelengths does enhance the ability to detect the red to far-red component of algae and orange/red-coloured conspecifics, possibly enabling social signalling. Character state reconstructions indicate that in the early evolutionary history of damselfishes, there was no lws expression and no orange/red coloration. Omnivory was most often the dominant state. Although herbivory was sometimes dominant, zooplanktivory was never dominant. Sensitivity to long wavelength (increased lws expression) only emerged in association with algivory but never with zooplanktivory. Higher lws expression is also exploited by social signalling in orange/red, which emerged after the transition to algivory. Although the relative timing of traits may deviate by different reconstructions and alternative explanations are possible, our results are consistent with sensory bias whereby social signals evolve as a correlated response to natural selection on sensory system properties in other contexts.

Honesty in signalling games is maintained by trade-offs rather than costs

BackgroundSignal reliability poses a central problem for explaining the evolution of communication. According to Zahavi’s Handicap Principle, signals are honest only if they are costly at the evolutionary equilibrium; otherwise, deception becomes common and communication breaks down. Theoretical signalling games have proved to be useful for understanding the logic of signalling interactions. Theoretical evaluations of the Handicap Principle are difficult, however, because finding the equilibrium cost function in such signalling games is notoriously complicated. Here, we provide a general solution to this problem and show how cost functions can be calculated for any arbitrary, pairwise asymmetric signalling game at the evolutionary equilibrium.ResultsOur model clarifies the relationship between signalling costs at equilibrium and the conditions for reliable signalling. It shows that these two terms are independent in both additive and multiplicative models, and that the cost of signalling at honest equilibrium has no effect on the stability of communication. Moreover, it demonstrates that honest signals at the equilibrium can have any cost value, even negative, being beneficial for the signaller independently of the receiver’s response at equilibrium and without requiring further constraints. Our results are general and we show how they apply to seminal signalling models, including Grafen’s model of sexual selection and Godfray’s model of parent-offspring communication.ConclusionsOur results refute the claim that signals must be costly at the evolutionary equilibrium to be reliable, as predicted by the Handicap Principle and so-called ‘costly signalling’ theory. Thus, our results raise serious concerns about the handicap paradigm. We argue that the evolution of reliable signalling is better understood within a Darwinian life-history framework, and that the conditions for honest signalling are more clearly stated and understood by evaluating their trade-offs rather than their costs per se. We discuss potential shortcomings of equilibrium models and we provide testable predictions to help advance the field and establish a better explanation for honest signals. Last but not least, our results highlight why signals are expected to be efficient rather than wasteful.

The Road to Open News: A Theory of Social Signaling in an Open News Production Community

ABSTRACT This study theorizes the role of social signals in overcoming the motivation, coordination, and integration challenges in a hybrid peer production community, WikiTribune. WikiTribune was a collaborative journalism project that combined elements of firm-based production with that of commons-based peer production. Empirical data (article metrics, project documentation, and user communications) was used to examine the first 18-months of building and developing the collaborative journalism platform and community. The study’s primary contribution is a social signaling model that extends the theory of commons-based peer production and presents three constructs that inform the socially productive behavior in these communities. These constructs (1) system signals, (2) normative signals, and (3) behavioral signals are theorized to shape user engagement through the different levels of project participation. The alignment/misalignment of these signals with project strategy produce positive or negative outcomes. The social signaling model seeks to explain how challenges are overcome and advantages leveraged in commons-based peer production, in both pure and hybrid forms.

To colour a bird: The evolution of carotenoid-based colouration in passerines is shaped by sexual selection, ecology and life history.

Research Highlight: Delhey, K., Valcu, M., Dale, J., & Kempenaers, B. (2022). The evolution of carotenoid-based plumage colours in passerine birds. Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.13791. Carotenoids, a class of colour pigments, are responsible for red, yellow and orange hues in nature. They play an important role in visual animals, and specially birds, where dietary carotenoids can act as honest sexual signals. Long-standing interest in the function of carotenoid-based colours has led to different hypotheses for their evolutionary drivers. Yet, comparative studies testing the generality of these hypotheses have been previously limited in phylogenetic scope or resolution. In a recent study, Delhey et al. (2022) combined sexual dichromatism, life history and environmental data to investigate the evolution of carotenoid-based colouration in the largest avian radiation, the passerines (Order: Passeriformes). The authors show that the expression of carotenoid-based colours depends on environmental availability, dietary content and body size. They also show that red carotenoids are more often evolutionarily and metabolically derived, and suggest different colours are favoured by natural and sexual selection. These findings shine new light on commonly held hypotheses of carotenoid-colour evolution and contribute to our understanding of how phenotypic diversity evolves.

Iridescent Beetle Adornments Suggest Incipient Status Competition among the Earliest Horticulturalists in Bears Ears National Monument

AbstractAnthropological research has long theorized that emergent food-producing economies catalyzed high levels of inequality in human societies, as evident in the earliest use of jewelry made from gold, copper, and other precious minerals among early agricultural populations. Although the US Southwest appears to have been an exception, we report the discovery of two Basketmaker II period necklaces constructed of green iridescent scarab beetle femora, which suggests a homologous association between emergent agriculture and inequality. Drawing insight from ethnography, archaeology, entomology, and evolutionary ecology, we hypothesize that these and other jewelry items of Basketmaker II culture were visually prominent, honest signals of socioeconomic capital that emerged during a period of surplus food production and incipient wealth accumulation. It appears that Basketmaker II societies—like other emergent food-producing economies around the world—grappled with the opportunities and challenges that arise with surplus production, albeit in a distinct way that involved visually striking insect and feather adornments as status signals. Archaeologists may have previously overlooked this behavior due to Western biases that privilege precious metals and minerals as prestige objects and archaeological biases that tend to view insects as food or agents of site disturbance.

Pervasive signaling

How does the increasing publicness of decisions (due, e.g., to social media) affect the total costs of social signaling distortions? While pervasive signaling may induce pervasive distortions, it may also permit people to signal while distorting each choice to a smaller degree. Ironically, for a broad class of environments, a sufficient increase in the number of signaling opportunities allows senders to “live authentically,” that is, to signal their types at arbitrarily low overall cost. This result survives when social networking technologies expand signaling opportunities and audience size in tandem, provided the returns to the latter are not too great.

Faded neural projection from the posterior bed nucleus of the stria terminalis to the lateral habenula contributes to social signaling deficit in male BTBR mice as a mouse model of autism

BTBR T+ Itpr3tf/J (BTBR) mice display several behavioral characteristics, including social deficits resembling the core symptoms of human autism. Atypical social behaviors include sequential processes of assembled cognitive-behavior components, such as recognition, investigatory assessment, and signaling response. This study aimed to elucidate the neural circuits responsible for the regulation of the social signaling response, as shown by scent marking behavior in male mice. We first assessed the recognition and investigatory patterns of male BTBR mice compared to those of C57BL/6 J (B6) mice. Next, we examined their scent-marking behavior as innate social signaling responses adjusted to a confronted feature of social stimuli and situations, along with the expression of c-Fos as a marker of neuronal activity in selected brain areas involved in the regulation of social behavior. The function of the targeted brain area was confirmed by chemogenetic manipulation. We also examined the social peptides, oxytocin and vasopressin neurons of the major brain regions that are associated with the regulation of social behavior. Our data indicate that male BTBR mice are less responsive to the presentation of social stimuli and the expression of social signaling responses, which is paralleled by blunted c-Fos responsivity and vasopressin neurons morphological changes in selected brain areas, including the posterior bed nucleus of the stria terminalis (pBnST) and lateral habenula (LHb) in BTBR mice. Further investigation of LHb function revealed that chemogenetic inhibition and activation of LHb activity can induce a change in scent marking responses in both B6 and BTBR mice. Our elucidation of the downstream LHb circuits controlling scent marking behavior indicates intact function in BTBR mice. The altered morphological characteristics of oxytocin neurons in the paraventricular nucleus of the hypothalamus and vasopressin-positive neurons and axonal projections in the pBnST and LHb appear to underlie the dysfunction of scent marking responses in BTBR mice.(300/300 words)

Oscillating flower colour changes of Causonis japonica (Thunb.) Raf. (Vitaceae) linked to sexual phase changes

Flower colour change may represent an ‘honest signal’ for pollinators, denoting flowers with good conditions for rewards and pollination. All previously reported flower colour changes are unidirectional, except for an incomplete case in one Fabaceae species. In this study, we discovered a very rare example of complete oscillating flower colour change associated with sexual phase changes in Causonis japonica (Vitaceae). More specifically, flower discs of C. japonica exhibit an orange colour in the initial male phase then soon fade into pink with desorption of the stamens. Several hours later in the daytime of the same or the following day, with stigma maturation and style elongation, the orange flower disc colour is recovered before fading into pink again. Importantly, we found that the colour change is caused by the accumulation and the degradation of carotenoids. Moreover, nectar secretion was roughly correlated with the abovementioned colour changes. This is the first example of an apparent oscillating colour change mediated by carotenoid content alteration in flowers.