Throat Patch Research Articles

Divergent ornamentation within a single population of the barn swallow.

Differential migration strategies favour different sets of characteristics, including sexually selected ornamentation. Such phenotypic variation is particularly evident in a population with partial migration, where migrants and non-migrants co-exist. Partial migration provides insights into the link between migration, local environment and ornamentation, although empirical studies remain scarce. Here, we studied the plumage traits of barn swallows (Hirundo rustica) in southern Japan, where both winterings and migrants breed sympatrically. We further examined this relationship with multiple isotopes (δ2H, δ13C, δ15N and δ34S), which provides insight into their moulting habitat. Among males, winterings and migrants differed in their morphological traits: wintering males had shorter wings, which suggests the high demand for flight apparatus in migratory birds. Moreover, wintering males had larger white tail spots and less colourful throat patches than migratory males, indicating ornament divergence between them. Wintering males had a significantly smaller isotopic space when examining the combinations of δ34S with the other isotopes compared to migratory males, which indicates a differential geographic range between them, perhaps because of the limited variation in the distance to the sea in wintering males. As in males, wintering females had a significantly smaller isotopic space than migrant females, but there were few morphological differences between migratory and wintering females. Instead, some morphological traits were related to isotope values in females. These results indicate sex-specific linkage between migration, local environment, and ornamentation.

Sperm Size Decreases With Increasing Pheomelanin Pigmentation but Not With the Amount of Glutathione in the Barn Swallow.

Pigment-based coloration is prevalent in animals, but its expression greatly varies across species, populations, and even among individuals in the same populations. Some animals are highly pigmented and thus have conspicuous coloration, whereas others are modestly pigmented and thus have drab coloration. A possible explanation for the variety in pigmentation is a resource-based tradeoff, in which resources invested in pigmentation are unavailable for other functional traits, and thus animals that need to invest in the latter have limited resources to invest in pigmentation. Resource-based tradeoff is plausible in theory, but direct tests are scarce, partially because of many components of pigment-based coloration (i.e., multiple pigments, integument microstructure, and stains) that affect coloration, preventing the use of coloration as an index of pigmentation. Here, using the barn swallow, Hirundo rustica, we examined the relationship between pheomelanin pigmentation in reddish throat patch (a precopulatory sexual trait) and total sperm length (a postcopulatory sexual trait), with particular attention to glutathione as the common resource. We predicted that pheomelanin, which is the predominant pigment in the reddish throat patch, should be negatively related to total sperm length, and that both sexual traits should be further negatively related to the amount of glutathione. As predicted, we found a negative relationship between pheomelanin pigmentation and total sperm length. However, the amount of glutathione in the blood showed no detectable relationship to them. The tradeoff between pheomelanin pigmentation and sperm size, as inferred from the current and previous results, might not be a simple glutathione-based tradeoff.

Flexible Throat Patch for Phonetic Recognition and Ingestion Monitoring via Sensory Transition based on Machine Learning (Adv. Mater. Technol. 10/2024)

Flexible Throat Patch for Phonetic Recognition and Ingestion Monitoring via Sensory Transition based on Machine Learning (Adv. Mater. Technol. 10/2024)

Flexible Throat Patch for Phonetic Recognition and Ingestion Monitoring via Sensory Transition based on Machine Learning

AbstractThe throat is an organ that includes the larynx, esophagus, and bronchi. Vocalization or deglutition triggers micro‐movements of muscles around the throat. In this study, based on machine learning using a flexible patch, pronunciation is identified by analyzing the vibration and movement of the laryngeal muscles, and the type of food consumed is determined through peristalsis analysis. Previously, voices are recognized through cochlea hair cells, and the type of food intake is identified through taste receptors. However, this study converted auditory or gustatory senses to tactile stage through sensory transition and finally visualized. Using a customized throat patch with segmented nodes, the pronunciation of [a], [e], [i], [o], and [u], representative vowels of languages worldwide, are distinguished with an accuracy of 85.9% based on the polynomial kernel algorithm. In addition, cookies, water, gummies, and chocolate are distinguished with 91.1% accuracy by detecting differences in the esophagus's peristalsis. Transformation of auditory or gustatory sensations to tactile information and visualization is expected to be used for communication in noisy environments or soundless environments such as outer space. This approach can also provide significant potential for determining the type of ingestion for users who have lost their sense of taste.

Nanomaterials-enhanced, stretchable, self-healing, temperature-tolerant and adhesive tough organohydrogels with long-term durability as flexible sensors for intelligent motion-speech recognition

Conductive hydrogels are flexible artificial materials that are promising for a broad range of applications such as wearable sensors for healthcare and exercise monitoring, electronic skins and soft robotics. However, conventional hydrogels are inevitably confronting several limitations on service life, long-term stability, and usability in extreme environments. Herein, a temperature-tolerant (-30 ∼ 60 °C), stretchable (3734 %), adhesive (220 kPa at porcine skin), self-healing and conductive tough organohydrogel is facilely developed through in situ free radical polymerization followed by glycol solvent replacement for flexible strain sensors. The organohydrogel-based sensor exhibits excellent reliability and a wide sensing range (5 %-1500 %) to precisely monitor human joint movements, wrist pulses, micro-expressions and vocal signals. Besides, the excellent mechanical and electrical properties of the obtained organohydrogel could be retained even after being treated under harsh environment (-30 °C for 24 hrs/60 °C for 96 hrs) or stored in ambient condition for up to 60 days. Furthermore, the organohydrogel could be integrated within a throat patch and wristband for exercise guidance based on its excellent sensing performances on both voice and postural recognitions in real time, which is envisioned to correct posture and improve the training effects of athlete. Thus, the developed organohydrogel sensor holds great promise as wearable devices for intelligent speech-motion recognition, rehabilitation training and human–computer interaction.

Fighting ability, personality and melanin signalling in free-living Eurasian tree sparrows (Passer montanus).

BackgroundIndividuals’ access to resources is often decided during dyadic contests the outcome of which is determined by the fighting (or competitive) ability of the participants. Individuals’ fighting ability (termed also as resource-holding power or potential, RHP) is usually associated with individual features (e.g., sex, age, body size) and is also frequently signalled through various ornaments like the black throat patch (bib) in many birds. Individual personality is a behavioural attribute often linked to fighting ability as well. Based on earlier studies, however, the relationship between personality and fighting ability is far from being straightforward. While accounting for sex and body size, we studied whether exploratory behaviour, an aspect of personality, predicts fighting ability when competing for food during winter in free-living Eurasian tree sparrows (Passer montanus). We also investigated whether the bib can serve as a potential indicator of individual competitiveness in this species.MethodsWe captured adult tree sparrows, marked them with a unique combination of colour rings, and collected data about the individuals’ sex, body size, bib size and exploratory behaviour. Birds were then released and the agonistic behaviour of the marked individuals was recorded while foraging in groups on bird feeding platforms.ResultsThe probability of winning a fight, a proxy for fighting ability of individuals, was not related to exploratory behaviour, in either of the sexes. However, bib size was positively related to probability of winning in females, but not in males. Body size was not associated with probability of winning neither in males, nor in females.ConclusionsOur results suggest that, at least in tree sparrows, the outcome of dyadic encounters over food during the non-breeding period are not determined by the exploratory personality of individuals. However, our findings provide further support for a status signalling role of the black bib in tree sparrows, and hint for the first time that bib size might function as a status signal in females as well. Finally, our results do not confirm that body size could serve as an indicator of fighting ability (i.e., RHP) in this species.

A revised multilocus phylogeny of Old World sparrows (Aves: Passeridae)

Abstract The Old World sparrows include some of the best-studied passerine species, such as the cosmopolitan human commensal, the house sparrow (Passer domesticus) as well as poorly studied narrow-range endemics like the Iago sparrow (P. iagoensis) from the Cape Verde Archipelago or specialists from extreme environments like the desert sparrow (P. simplex). It is therefore notable that to date the most complete phylogenetic hypothesis for the Old World sparrows comprised only ten of 43 currently accepted species. With this study we provide an updated phylogeny of Passeridae covering about two third of the family’s species richness. Though still being far from taxon-complete, this new phylogenetic hypothesis provides firm evidence to clarify some open taxonomic questions. All genus-level taxa were reciprocally monophyletic with strong support. Contrary to previous classifications, bush sparrows and rock sparrows were not sister taxa, and therefore their classification in separate genera Gymnoris and Petronia is justified. Plumage color traits like the yellow throat patch of the latter two genera or head color pattern in Passer species do not provide reliable phylogenetic information, except for the large-sized African grey-headed sparrows that resulted as a monophyletic group (P. diffusus, P. griseus, P. gongoensis). Unexpectedly, two small-sized species, P. eminibey and P. luteus that to date are regarded as close relatives were firmly nested in two separate clades of Passer sparrows. Therefore, their separate generic treatment under Sorella eminibey and Auripasser luteus (together with A. euchlorus) does not seem justified.

Exercise training has morph-specific effects on telomere, body condition and growth dynamics in a color-polymorphic lizard.

Alternative reproductive tactics (ARTs) are correlated suites of sexually selected traits that are likely to impose differential physiological costs on different individuals. While moderate activity might be beneficial, animals living in the wild often work at the margins of their resources and performance limits. Individuals using ARTs may have divergent capacities for activity. When pushed beyond their respective capacities, they may experience condition loss, oxidative stress, and molecular damage that must be repaired with limited resources. We used the Australian painted dragon lizard that exhibits color polymorphism as a model to experimentally test the effect of exercise on body condition, growth, reactive oxygen species (ROS) and telomere dynamics - a potential marker of stress and aging and a correlate of longevity. For most males, ROS levels tended to be lower with greater exercise; however, males with yellow throat patches - or bibs - had higher ROS levels than non-bibbed males. At the highest level of exercise, bibbed males exhibited telomere loss, while non-bibbed males gained telomere length; the opposite pattern was observed in the no-exercise controls. Growth was positively related to food intake but negatively correlated with telomere length at the end of the experiment. Body condition was not related to food intake but was positively correlated with increases in telomere length. These results, along with our previous work, suggest that aggressive - territory holding - bibbed males suffer physiological costs that may reduce longevity compared with non-bibbed males with superior postcopulatory traits.

Short-wavelength visual sensitivity and sexual differences in plumage colouration of ovenbirds (Aves: Furnariinae)

Ovenbirds represent a clade of exclusively Neotropical birds that are exceptionally diverse, despite their rather dull, melanin-based plumage. In general, sexes are considered monomorphic in size and colour, but several authors have reported females of some species within this family as being slightly paler than their conspecific counterparts. Our aim was to assess levels of sexual dichromatism in a set of ovenbird species representing a diversity of genera and plumage patterns; Furnarius rufus, Phleocryptes melanops, Synallaxis spixi and Schoeniophylax phryganophilus. For each species, we quantified sexual differences in brightness and colouration among 8–10 different plumage regions through modelling avian perceptual colour-space distances. To best inform our visual modelling parameters, we successfully sequenced the SWS1 gene fragment (associated with short-wavelength, including ultraviolet, visual sensitivity in birds) for one species, P. melanops, and found it possessed an amino acid sequence consistent with the VS-type SWS1 visual system. This provides further evidence supporting the presence of VS-sensitive opsin in ovenbirds. Among all four species, females were consistently brighter than males in at least one plumage patch, but chromatic colour differences between sexes were significant only for the throat patches of Schoeniophylax phryganophilus. Overall, we interpret ovenbirds to exhibit very low levels of sexual dichromatism, manifest mainly by achromatic colour differences.

Genomic and plumage variation in Vermivora hybrids

AbstractHybrids with different combinations of traits can be used to identify genomic regions that underlie phenotypic characters important to species identity and recognition. Here, we explore links between genomic and plumage variation in Blue-winged Warbler x Golden-winged Warbler (Vermivora cyanoptera x V. chrysoptera) hybrids, which have traditionally been categorized into 2 discrete types. “Lawrence’s” hybrids are yellow overall, similar to Blue-winged Warblers, but exhibit the black throat patch and face mask of Golden-winged Warblers. “Brewster’s” hybrids are similar to Golden-winged Warblers, but lack the black throat patch and face mask, and sometimes have yellow on their underparts. Previous studies hypothesized that (1) first generation hybrids are of the Brewster’s type and can be distinguished by the amount of yellow on their underparts, and that (2) the throat patch/mask phenotype is consistent with Mendelian inheritance and controlled by variation in a locus near the Agouti-signaling protein (ASIP) gene. We addressed these hypotheses using whole genome re-sequencing of parental and hybrid individuals. We found that Brewster’s hybrids had genomic hybrid index scores indicating this phenotype can arise by majority ancestry from either parental species, that their plumage varied in levels of carotenoid pigmentation, and individuals captured in multiple years grew consistently less yellow over time. Variation in carotenoid pigmentation showed little relationship with genomic hybrid index score and is thus inconsistent with previous hypotheses that first generation hybrids can be distinguished by the amount of yellow in their plumage. Our results also confirm that variation near ASIP underlies the throat patch phenotype, which we refined to an ~10–15 Kb region upstream of the coding sequence. Overall, our results support the notion that traditional categorization of hybrids as either Lawrence’s or Brewster’s oversimplifies continuous variation in carotenoid pigmentation, and its inferred underlying genetic basis, and is based primarily on one discrete trait, which is the throat patch/mask phenotype.

Covariation in superoxide, sperm telomere length and sperm velocity in a polymorphic reptile

Telomeres are DNA-protein caps at the ends of chromosomes that have been shown to be associated with male fertility may be heritable, reflect environmental influences and predict life span in some taxa. If heritable, paternal telomere length would be transmitted via sperm in the form of sperm telomere length (STL). We, therefore, investigated STL, sperm number and velocity in the Australian-painted dragon lizard, Ctenophorus pictus, an agamid lizard with distinct male colour morphs and related reproductive tactics. We measured telomere length in the sperm and blood as well as superoxide levels, as a measure for the potential for oxidative stress and ejaculate quality. We also noted a male’s head colour (red, orange, yellow or blue) and whether or not they had a yellow gular bib. Previous research has reported that yellow males outcompete red males in sperm competition; we found that yellow males had significantly shorter STL than red males. Males with bibs had greater STL than did males without bibs. Superoxide levels measured in the blood were negatively correlated with STL. Whole blood TL and body length were weakly but positively correlated with STL. Superoxide measurements were negatively correlated with progressive sperm motility and straight line sperm velocity across all males. The ejaculates of males with bibs had lower sperm counts and velocity than males without bibs. Our research adds to the growing research that indicates the importance of considering both somatic and gametic telomeres when assessing the interaction between telomere dynamics, life history and reproductive strategies. Telomeres are DNA-protein caps at the ends of chromosomes that reflect environmental stress may be heritable and epigenetically modified, may predict life span in some taxa and may influence the probability of paternity in sperm competition. Ours is one of the first studies to examine correlates of sperm telomere length in a non-mammalian, polymorphic species, but much more remains to be done. Telomere research in non-model species has focused on survival consequences of variation in telomere traits with less attention paid to the fact that sperm (and egg) telomere biology can link life history traits directly to reproductive physiology. We chose to investigate sperm velocity and sperm telomere length (STL) in the painted dragon lizard, Ctenophorus pictus, an agamid lizard with distinct male morphs and associated reproductive tactics. We also observed morph-specific differences in ejaculate quality and STL; in particular, males with yellow bibs had longer STL but poorer ejaculate quality metrics (e.g., number of sperm, velocity and proportion of progressively motile sperm) than males without the throat patch. The differences in STL between the morphs and the negative relationship between sperm velocity and STL, along with previous work on this species, suggest that telomere length and dynamics may be linked with the reproductive tactics of colour morphs within this species.

The relationship of body condition, superoxide dismutase, and superoxide with sperm performance

AbstractSperm competition theory predicts a negative correlation between somatic investment and traits that aid in pre- and postcopulatory sexual selection. Sperm performance is critical for postcopulatory success but sperm are susceptible to damage by free radicals such as superoxide radicals generated during mitochondrial respiration (mtSOx). Males can ameliorate damage to spermatozoa by investing in the production of antioxidants, like superoxide dismutase (SOD), which may act as a mechanistic link to pre- and postcopulatory trade-offs. Some male Australian, color-polymorphic painted dragon lizards (Ctenophorus pictus) possess a yellow throat patch (bib) that females prefer over nonbibbed males and are also more likely to win male–male contests indicating that males with bibs may be better at monopolizing females. We tested whether the sperm performance in nonbibbed males was superior to that of bibbed males. We show that overall sperm performance was not different between the bib-morphs, however, higher mtSOx levels were negatively correlated with sperm performance in bibbed males, but not of nonbibbed males. Blood cell mtSOx levels are negatively correlated with SOD activity in the plasma in all males early in the breeding season but SOD was lower in bibbed males. Nonbibbed males maintain a positive correlation between body condition and SOD activity over time while bibbed males do not. Together, these data suggest physiological associations between body condition, SOD activity, and sperm performance are linked to the expression of a yellow gular patch, which may be related to intrinsic differences in the metabolism of bibbed versus nonbibbed males.

Intraseasonal Changes of Patch Color in Prairie Lizards (Sceloporus Consobrinus)

Abstract Many sexually selected traits are static throughout the breeding season. Some vary within the breeding season, however, typically in response to physiological changes. Most work attempting to understand the mechanisms underlying phenotypic changes has occurred in the laboratory, with comparatively less research examining how changes to physiology affect signal production in natural populations. Here, we report intraseasonal plasticity in abdominal and throat patch color of Prairie Lizards (Sceloporus consobrinus), and examine how changes in body size, body condition, and testosterone underlie intraseasonal variation. We found that changes in testosterone best explain why throat patches of Prairie Lizards become less blue throughout the breeding season. If females reproduce with males based on patch color, then individual changes in patch phenotypes could have important consequences if signaling morphology is asynchronous among males.

Males with More Pheomelanin Have a Lower Oxidative Balance in Asian Barn Swallows (Hirundo rustica gutturalis).

Pheomelanin-based plumage pigmentation has been suggested to be an honest signal of individual quality to conspecifics. It has been hypothesized that oxidative stress is an important agent linking pheomelanic pigmentation to individual quality. Using the Asian barn swallow Hirundo rustica gutturalis, a wild passerine, we tested whether the pheomelanin pigmentation in the red throat patch of adult males, a sexually selected trait, is associated with the ratio between reduced and oxidized glutathione (RGSH/GSSG) as an indicator of current oxidative balance during the early breeding season. We found that males with a higher pheomelanin concentration in their throat feathers had a significantly lower RGSH/GSSG ratio (i.e., higher oxidative stress), but exhibited a better body condition, measured as residual body mass on body size, compared to males with a lower pheomelanin concentration. The total GSH level was not significantly related to the pheomelanin concentration. These findings suggest a negative association between the red pheomelanin pigmentation and oxidative balance during mating and reproductive efforts, which might be mitigated by high-quality males. Further research is needed to understand its actual damage and mitigation mechanism.

Delayed plumage maturation in green‐backed flycatchers (Ficedula elisae): An evidence of female mimicry

Delayed plumage maturation (DPM) is the delayed acquisition of an adult color and pattern of plumage until after the first potential breeding period. Among the hypotheses proposed to explain DPM, the female mimicry hypothesis (FMH) has received considerable attention. FMH predicts that after-second-calendar-year (ASY) males should attack ASY males more than second-calendar-year (SY) males and females, while no difference between the two latter. Few studies have been thought as support for FMH, while in fact most of them give no conclusive evidence to the assumption of FMH that ASY males are unable to distinguish SY males from females. Thus, other support besides behavioral experiments, such as it is physiologically impossible to discriminate SY males and females from avian perspective, is important in testing FMH. We studied color differences in six plumage patches between ASY male, SY male and female by analyzing reflectance spectra in the avian visual system, and tested the prediction of FMH by conducting intrusion experiments on territorial males with three kinds of conspecifics (i.e., ASY males, SY males and females) as territory “intruders” in the green-backed flycatcher (Ficedula elisae). It is physiologically impossible for ASY males to distinguish SY males and females through the plumage color of crown, mantle, rump, and throat patches, moreover difficult to distinguish through breast and belly patches even under reasonable viewing conditions. ASY males were more aggressive toward ASY males than SY males and females with no differences between the two latter. SY males showed a slightly but not significantly higher attack intensity on ASY males than SY males and females. Our results suggest that female mimicry is more likely to be the explanation for DPM in the green-backed flycatcher. To our knowledge, this is the first study combining avian visual system and behavioral experiments in testing hypotheses of DPM.

Covariation between Thermally Mediated Color and Performance Traits in a Lizard

Physiological changes in response to environmental cues are not uncommon. Temperature has strong, predictable effects on many traits, such that many traits in ectotherms follow stereotyped thermal performance curves in response to increasing temperature. The prairie lizard-an abundant lizard throughout the central United States-has thermally sensitive, blue abdominal and throat patches. Currently, the role of these patches is not well understood. In this study, we set out to investigate whether individual plasticity in patch color paralleled individual plasticity in sprint speed (do they covary), and if the plasticity in these two patches signal redundant or independent information, testing competing hypotheses suggested for the evolution of multiple signals. We found that both abdominal and throat patch hue follow classical thermal performance curves, suggesting that at the species level hue is a good predictor of sprinting ability. At the individual level, we found that color and performance were statistically repeatable, so individuals with relatively high phenotypic values maintain relatively high phenotypic values across all temperatures. Additionally, we found that abdominal and patch hue covary with sprinting speed at the individual level. Together, these results suggest that the bluest individuals are the fastest individuals across temperatures. However, we found that abdominal and throat patch hue do not covary with each other at the individual level, suggesting that these signals may have independent functions. The importance of examining the function of individual variation cannot be overstated, and overall, more work is needed to better understand both the proximate and ultimate mechanisms underlying signal plasticity in this species and others.

Sexual Selection Mechanisms for Male Plumage Ornaments in Japanese Barn Swallows

The Barn Swallow Hirundo rustica is a model species for studying sexual selection. After its long tail was shown to be the target of female mate choice, its plumage characteristics, including the red throat patch and the size of white tail spots in addition to tail length, have attracted the attention of many researchers. Although there have been several reviews of sexual selection in this species, these reviews have focused mostly on general patterns of sexual selection within and among subspecies, rather than on the functional differences between plumage characteristics in sexual selection. Here, I review mechanisms of sexual selection for male plumage ornaments in Japanese Barn Swallows H. r. gutturalis. In the last decade, studies of sexual selection in Japanese Barn Swallows have focussed on tail length, the size of the white tail spots, and the size and coloration of red throat patches. Each ornamental trait appears to be involved in different sexual selection mechanisms: the size of the white tail spots is important for several mechanisms of intersexual selection, including the Darwin-Fisher mechanism and differential allocation, whereas throat coloration may be intra-sexually selected, at least in part. The size of the throat patch, in contrast, is the target of an intersexual selection mechanism, differential access, indicating a partially independent evolution of the two components of the red throat patch. Multiple mechanisms of sexual selection would explain the multiple ornaments and their geographical variation, and even the probability of speciation and extinction.

The fractal dimension of a conspicuous ornament varies with mating status and shows assortative mating in wild red-legged partridges (Alectoris rufa).

Complex body designs, such as plumage ornaments in birds, can be described by fractal geometry. These complex patterns could have a role as visual signals during courtship and social interactions, but an empirical validation in the wild is currently lacking. Here, we investigated whether the fractal dimension (FD) of a complex plumage pattern displayed by red-legged partridges Alectoris rufa could function as a potential sexual signal. We captured wild birds early in the breeding season and tested if mated and unmated birds differed in the FD of their conspicuous melanin-based black bib. We also tested if the FD of the black bib was correlated within the pair, looking for evidence of assortative mating based on the expression of this trait. We simultaneously assessed similar effects in other ornamental traits (black bib size, white throat patch and black flank band surface, redness of the eye rings and bill). Mated birds showed higher black bib FD values than unmated ones. Mated males, but not females, also displayed a larger black bib. Moreover, the black bib FD (but not the trait size) and the white throat patch surface showed assortative mating. Finally, females with higher black bib FD showed smaller black flank band surface, suggesting a trade-off in the expression of the two melanin-pigmented plumage traits. This provides unique and novel indication for the shape complexity of a pigmented trait, here described by its fractal dimension, to be potentially under sexual selection in a wild animal.

Two ways to display: male hummingbirds show different color-display tactics based on sun orientation

Male broad-tailed hummingbirds use 2 different courtship-display tactics to show off their iridescent throat coloration based on how they orient to the sun. Some males tended to face the sun while courting females, creating a flashy color-display, while others tended to not face the sun, making them appear consistently colorful. The males with flashier displays were better able to maintain their orientation toward females, while males who appeared more consistently colored had larger throat patches.

Throat Patch Variation in Tayra (Eira barbara) and the Potential for Individual Identification in the Field

The importance of identifying individuals of a population has been extensively documented in several species of carnivores, including some species of mustelids. This information is used in many kinds of ecological studies including density estimation, behavioral ecology and analyses of animal movement patterns. The objective of the present study was to determine if individual variation in the throat patches of Tayra (Eira barbara) permits individual identification. We examined 275 specimens from museum collections to determine the morphological variation of the throat patch in Eira barbara specimens collected throughout its distribution. We found differences in the shape and size of the throat patches significant enough to allow discrimination of individuals that display a throat patch (88.0% of 252 complete specimens). The proposed identification criterion was applied to photographic records obtained from a wild population using camera traps in the Peruvian Amazon. From nineteen images (54.0% of all images) in which the throat patch was visible, nine different individuals were identified and two of these were recaptured on multiple occasions.