Use Of Chemical Cues Research Articles

The Hidden World of Insect-Plant Interactions: a review

This review examines the hidden world of plant-insect interactions by emphasizing on the sensory perception and behavior of phytophagous insects, nutritional influence on insect reproduction, host plant resistance, Insects, weed and crop interaction, Insect pollinator plant interaction, tri-trophic interaction, and insect biotechnology. It explores how insects use sensory cues to forage for food, find mates, perceive dangers, and navigate their environment. It also examines the influence of host plants on insect behavior and the use of chemical cues for communication. The potential use of semio-chemicals in pest management for sustainable agriculture is highlighted. Nutritional factors and their impact on insect reproductive success are also discussed, emphasizing the need for balanced diets. The different categories of host plant resistance and their effects on insects are examined. The interdependent relationships between insects, plants, and weeds in agricultural ecosystems are explored, with a focus on the role of insect pollinators. The decline of insect pollinators and the importance of studying them are emphasized. The importance of tri-trophic interactions in maintaining ecological balance and biodiversity is discussed. Moreover, the role of biotechnological techniques like genomics, proteomics, transcriptomics, and epigenetics in understanding insect plant interactions as well as developing insect pest control strategies is discussed. The potential use of natural products produced by plants in environmentally friendly pest control methods is also examined. Overall, this review provides a comprehensive exploration of insect-plant interactions and the potential for sustainable pest control methods.

A learning experience elicits sex-dependent neurogenomic responses in Bicyclus anynana butterflies.

Sexually dimorphic behaviour is pervasive across animals, with males and females exhibiting different mate selection, parental care, foraging, dispersal, and territorial strategies. However, the genetic underpinnings of sexually dimorphic behaviours are poorly understood. Here we investigate gene networks and expression patterns associated with sexually dimorphic imprinting-like learning in the butterfly Bicyclus anynana. In this species, both males and females learn visual preferences, but learn preferences for different traits and use different signals as salient, unconditioned cues. To identify genes and gene networks associated with this behaviour, we examined gene expression profiles of the brains and eyes of male and female butterflies immediately post training and compared them to the same tissues of naïve individuals. We found more differentially expressed genes and a greater number of associated gene networks in the eyes, indicating a role of the peripheral nervous system in visual imprinting-like learning. Females had higher chemoreceptor expression levels than males, supporting the hypothesized sexual dimorphic use of chemical cues during the learning process. In addition, genes that influence B. anynana wing patterns (sexual ornaments), such as invected, spalt, and apterous, were also differentially expressed in the brain and eye, suggesting that these genes may influence both sexual ornaments and the preferences for these ornaments. Our results indicate dynamic and sex-specific responses to social scenario in both the peripheral and central nervous systems and highlight the potential role of wing patterning genes in mate preference and learning across the Lepidoptera.

Onto the sense of smell in macaws, amazons and toucans: can they use volatile cues of fruits to make foraging decisions?

Over the past decades, empirical evidence has been accumulated indicating that olfactory information plays a fundamental role in bird life history. Nonetheless, many aspects of avian olfaction remain poorly understood. Our purpose was to broaden the knowledge about the importance of the sense of smell in some neglected bird groups: psittaciformes and ramphastids, and to compare how the response varied between the species. Because of the lack of information about the use of chemical cues for locating food in fruit-eating species, we also aimed to delve into this question. We conducted a 3-choice (water/vinegar/papaya and banana juice) scent test in 5 Costa Rican native species: scarlet macaw (Ara macao), red-lored amazon (Amazona autumnalis), yellow-naped amazon (Amazona auropalliata), keel-billed toucan (Ramphastos sulfuratus), and yellow-throated toucan (Ramphastos ambiguus). Results revealed that macaws and toucans allocated significantly more time to interacting with the fruit scent container, indicating that these species can perceive the volatile chemicals emitted by ripe fruits and that they can use this information to make foraging decisions. However, amazons did not dedicate more time to interact with the fruit treatment. Our research provides the first evidence of the ability to exploit chemical volatile cues in macaws and toucans.

The Use of Chemical Cues by Sargassum Shrimps Latreutes fucorum and Leander tenuicornis in Establishing and Maintaining a Symbiosis with the Host Sargassum Algae

A mutualistic symbiosis exists between the alga Sargassum spp. and two shrimp species, Latreutes fucorum and Leander tenuicornis. However, little is known about how these shrimp locate and establish their host alga. Both visual and chemical cues are potentially available. A previous study has looked at both cue variables with results that are mixed. Specifically, these same shrimp species used chemical cues only when visible cues were available simultaneously. Visual cues would be presumably restricted at night, but chemical cues are potentially available continuously. This current research elaborates on the previous study to fully understand Sargassum shrimp chemoreception. Increases in sample sizes and both a 4-chambered and Y-maze apparatus were used to test whether the shrimp could detect Sargassum cues, dimethylsulfoniopropionate (DMSP) (a chemical excreted by some marine algae), and conspecific cues. Neither shrimp species showed a strong directional response to any of the chemical cues, but the Sargassum and DMSP cues did cause more shrimp to exhibit searching behavior. Additionally, several differences in responses between male and female shrimp were found for each cue. A lowered dilution of DMSP was also tested to determine sensitivity of L. fucorum shrimp to the chemical cue; although searching behavior was triggered, conclusions about quantifying the sensitivity could not be made. Overall, these results show the shrimp can detect chemical cues—in the absence of visual cues—that could affect initiating and maintaining this shrimp/algal symbiosis.

Chemical Ecology of the Parasitoid Wasp Genus Nasonia (Hymenoptera, Pteromalidae)

The use of chemical cues and signals is essential for communication in insects. Wasps of the genus Nasonia (Hymenoptera, Pteromalidae) are gregarious parasitoids that lay their eggs into puparia of cyclorrhaphous flies. During their life cycle, various kinds of semiochemicals are used: (1) a male abdominal sex pheromone that attracts females and induces site fidelity in males, (2) a female-derived contact sex pheromone eliciting courtship behavior in males, (3) an oral male aphrodisiac eliciting receptivity signaling in females and causing a switch in the females' olfactory preferences, (4) chemicals derived from host habitat and host puparia used in olfactory host finding by female wasps, and (5) chemicals used by females to assess the quality and parasitization status of potential hosts. We review the literature on the chemical ecology of Nasonia spp. following the wasps' life cycle from emergence to oviposition. We depict biosynthetic pathways where available, discuss ecological implications, highlight differences among Nasonia species, summarize insights into their olfactory perception and associative learning abilities, and point out gaps in our understanding of the chemical ecology of these parasitoids to be addressed in future studies.

The Use of Chemical Cues by Granite Night Lizards (Xantusia henshawi) to Evaluate Potential Predation Risk

Squamate reptiles have highly developed chemosensory systems used to detect both predators and prey. Although the general ability of squamates to assess predation risk using chemical cues is well known, the detail to which squamates can make discriminations concerning risk is largely unexamined. Granite Night Lizards (Xantusia henshawi) are habitat specialists that live in exfoliations of granite boulders in dense populations. We measured the responses of Granite Night Lizards to the scent of a sympatric predator, the Lyre Snake (Trimorphodon lyrophanes), maintained on two different diets (lizard-fed and mouse-fed), as well as a non-predatory snake (the Shovelnose Snake, Chionactis occipitalis) and a blank control. We also evaluated the potential use of conspecific chemical cues to assess predation risk by quantifying the response of lizards to the scent of both calm and stressed conspecifics. We collected scents for both experiments on paper pads, which we then placed at the entrance of a shelter within a testing arena containing a focal lizard. We then used video cameras to record the behavior of focal lizards over a 60-minute period. We found that, compared to the blank control, Night Lizards in the presence of chemical cues from snakes took longer to enter the shelter, spent longer investigating chemical cues, and traveled further before entering the shelter. Lizards also spent longer investigating chemical cues from Lyre Snakes than Shovelnose Snakes. However, there were no significant differences between responses to lizard-fed and mouse-fed Lyre Snake chemical cues. We also found no evidence that lizards use conspecific chemical cues to evaluate predation risk. This study demonstrates that Granite Night Lizards can use chemical cues from their predators to assess predation risk, but further research is needed to assess whether these responses differ based on the diet of the predator.

Innate Host Habitat Preference in the Parasitoid Diachasmimorpha longicaudata: Functional Significance and Modifications through Learning.

Parasitoids searching for polyphagous herbivores can find their hosts in a variety of habitats. Under this scenario, chemical cues from the host habitat (not related to the host) represent poor indicators of host location. Hence, it is unlikely that naïve females show a strong response to host habitat cues, which would become important only if the parasitoids learn to associate such cues to the host presence. This concept does not consider that habitats can vary in profitability or host nutritional quality, which according to the optimal foraging theory and the preference-performance hypothesis (respectively) could shape the way in which parasitoids make use of chemical cues from the host habitat. We assessed innate preference in the fruit fly parasitoid Diachasmimorpha longicaudata among chemical cues from four host habitats (apple, fig, orange and peach) using a Y-tube olfactometer. Contrary to what was predicted, we found a hierarchic pattern of preference. The parasitism rate realized on these fruit species and the weight of the host correlates positively, to some extent, with the preference pattern, whereas preference did not correlate with survival and fecundity of the progeny. As expected for a parasitoid foraging for generalist hosts, habitat preference changed markedly depending on their previous experience and the abundance of hosts. These findings suggest that the pattern of preference for host habitats is attributable to differences in encounter rate and host quality. Host habitat preference seems to be, however, quite plastic and easily modified according to the information obtained during foraging.

Elucidating the Life History and Ecological Aspects of Allodero hylae (Annelida: Clitellata: Naididae), A Parasitic Oligochaete of Invasive Cuban Tree Frogs in Florida.

Given their ubiquitous nature, it is surprising that more oligochaete annelid worms (Annelida: Clitellata) have not adopted an endoparasitic lifestyle. Exceptions, however, are the understudied members of the genus Dero (Allodero) that parasitize the ureters of tree frogs and toads. This study experimentally explores the life cycle and host specificity of Allodero hylae, the worm's use of chemical cues in host searching, and its seasonal prevalence and abundance over a year-long collection period on the Florida Southern College campus. A total of 2,005 A. hylae was collected from the ureter, urinary bladder, or expressed urine of wild Osteopilus septentrionalis ; a significant positive correlation was found between host snout-vent length and parasite intensity for female but not male hosts. Monthly prevalence of A. hylae reached a peak of 58% in April, but never dropped below 20% in any month; mean abundance peaked March-May, whereas few worms were recovered in December and January. Confirming a parasitic lifestyle, wild-collected hosts with intense infections, typically >40 worms, showed obvious dilatation of the ureter wall, and some young-of-the-year O. septentrionalis exposed to A. hylae in the laboratory were killed by the apparent rupture of the host's ureter. The worm has a direct life cycle: worms expelled in the host's urine are capable of locating and re-infecting other hosts within aquatic microhabitats such as bromeliad tanks, and worms can survive for weeks in a free-living environment, even undergoing a morphological change. Further, chemotaxis assays found a positive response to a tree frog attractant for worms recently removed from hosts. Overall, this study provides the first multifaceted investigation on the life history and ecology of any Allodero spp., which offers new insights into an understudied endoparasitic oligochaete.

Use of chemical cues by coral reef animal larvae for habitat selection

AB Aquatic Biology Contact the journal Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AB 19:231-238 (2013) - DOI: https://doi.org/10.3354/ab00532 Use of chemical cues by coral reef animal larvae for habitat selection David Lecchini1,2,*, Yohei Nakamura3 1USR 3278 CNRS-EPHE, CRIOBE, 98729 Moorea, French Polynesia 2Laboratoire d’Excellence ‘CORAIL’, 98729 Moorea, French Polynesia 3Graduate School of Kuroshio Science, Kochi University, 783 8502 Kochi, Japan *Email: lecchini@univ-perp.fr ABSTRACT: The present study explored the importance of chemical cues for habitat selection by fish (6 species), crustacean (1 species), and cephalopod (1 species) larvae in a 4-channel choice flume at Ishigaki Island, Japan. The larval attraction toward chemical cues from reef patches (seagrass bed patch, live coral patch, dead coral patch, and control water; Expt 1) and microhabitats within a given reef patch (live coral colonies, dead coral colonies, seagrass, and conspecifics; Expt 2) was tested in a 4-channel choice flume. The results in Expt 1 showed that 3 fish species used chemical cues to move significantly towards reef patches: Chromis viridis toward live coral patch water and Lutjanus fulviflamma and L. gibbus toward seagrass bed patch water. In Expt 2, 6 of 8 species (4 fishes, 1 cephalopod, and 1 crustacean) used chemical cues to move significantly toward conspecific water (Apogon properuptus, C. viridis, Dascyllus reticulatus, L. fulviflamma, Octopus cyanea, and Palaemonidae sp.). Overall, these results suggest that marine species can actively select settlement habitats according to olfactory cues (more specially, cues from conspecifics). Moreover, these results highlight the importance of conspecific cues over other types of information (reef patch and microhabitat) for habitat selection. Social aggregation of fish, crustacean, and cephalopod larvae with older conspecifics may be the result of individuals using conspecific ‘guides’ to potentially find beneficial resources (availability of resources and low mortality). KEY WORDS: Sensory mechanisms · Settlement cues · Fish · Crustacean · Cephalopod Full text in pdf format PreviousNextCite this article as: Lecchini D, Nakamura Y (2013) Use of chemical cues by coral reef animal larvae for habitat selection. Aquat Biol 19:231-238. https://doi.org/10.3354/ab00532 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AB Vol. 19, No. 3. Online publication date: October 24, 2013 Print ISSN: 1864-7782; Online ISSN: 1864-7790 Copyright © 2013 Inter-Research.

Orientation mechanisms and sensory organs involved in host location in a dipteran parasitoid larva

The robber fly Mallophora ruficauda is one of the principal pests of apiculture in the Pampas region of Argentina. Larvae are solitary ectoparasitoids of third-instar scarab beetle larvae. Females of M. ruficauda do not lay eggs on or near the hosts, but on tall grasses. After hatching, larvae are dispersed by the wind and drop to the ground, where they dig and search for potential hosts. It is known that second-instar larvae of M. ruficauda exhibit active host-searching behaviour towards their preferred hosts, i.e., third-instar larvae of Cyclocephala signaticollis. Although host-location seems to be mediated by chemical cues, the mechanism of orientation and the sensory organs involved in host location remain unknown. We carried out behavioural experiments in the laboratory to address these questions. We also tested whether the orientation behaviour is exclusively based on the use of chemical cues. We found that larvae of M. ruficauda detect the chemicals with chemosensilla on the maxillary palps. Only one maxillary palp suffices for orientation, but their bilateral ablation abolishes orientation. Besides, an hexane extract of the host body was as attractive as a live host. Our results support that M. ruficauda larvae find their hosts underground by means of chemoklinotaxis.

Pheromone Communication in Amphibians and Reptiles

This selective review considers herpetological papers that feature the use of chemical cues, particularly pheromones involved in reproductive interactions between potential mates. Primary examples include garter snake females that attract males, lacertid lizards and the effects of their femoral gland secretions, aquatic male newts that chemically attract females, and terrestrial salamander males that chemically persuade a female to mate. Each case study spans a number of research approaches (molecular, biochemical, behavioral) and is related to sensory processing and the physiological effects of pheromone delivery. These and related studies show that natural pheromones can be identified, validated with behavioral tests, and incorporated in research on vomeronasal functional response.

Multivariate statistics coupled to generalized linear models reveal complex use of chemical cues by a parasitoid

Understanding how animals integrate multiple cues, in particular complex mixtures of volatile chemicals, is a subject of current interest. Insect behavioural responses to volatile blends have traditionally been analysed separately to the changes in blends themselves, making it difficult to link behaviour directly to volatile cues. We coupled principal components analysis (PCA) and generalized linear models (GLMs) to link volatiles released by plants in response to pea aphid, Acyrthosiphon pisum, feeding directly to the behaviour of the aphid parasitoid Aphidius ervi. We used choice bioassays to compare parasitoid response to odours from aphid-damaged and undamaged plants, then collected volatiles from the same plants used in bioassays and analysed volatile profiles with PCA. The principal components explaining 99% of the variation in the data set were used as explanatory variables in a GLM to analyse the behavioural response. This was done for two plant species: alfalfa, Medicago sativa, and broad bean, Vicia faba. For each species, a single principal component was important in explaining insect attraction. In both cases it explained a small amount of variability in the volatile data set (7.0% and 0.5% in M. sativa and V. faba, respectively). For both plants, the analysis revealed the presence of volatiles that supported or inhibited parasitoid attraction. Compositional analysis of the blend revealed no major changes in either plant, highlighting that A. ervi can detect minor changes, ignoring the major variability in the blend. The approach could be valuable for behavioural studies on multisensory orientation by foraging animals.

Temporal variation in recognition cues: implications for the social life of weaver ants Oecophylla smaragdina

Recognition systems are involved in a range of evolutionary and biological processes, and animals use a variety of visual, auditory, tactile and olfactory cues to determine the status of others. The use of chemical cues is widespread, occurring among mammals, fish, reptiles and birds, but particularly among insects. Yet chemical cues may be influenced by diet and environment, and can change over time, potentially limiting their reliability as recognition cues. Nevertheless, they play a key role in colonymate recognition among social insects. We created colony isolates from large multinest colonies of weaver ants and asked (1) whether colony spectral profiles (determined using near-infrared spectroscopy) changed over time, (2) whether spectral profiles of colony isolates diverged from those of original colonies, and (3) whether the behaviour of original colonies towards colony isolates changed over time. Although we detected changes in the spectral profile of original colonies and colony isolates, they did not diverge significantly from each other. As far as we are aware, this is the first time that such parallel changes in colony odour have been observed. Aggression towards individuals from colony isolates did not increase, although levels of trophallaxis did. This demonstrates that colonymate recognition among weaver ants was unimpaired by temporal variation in recognition cues. We discuss the characteristics of weaver ants that might give rise to this system. We also discuss the implications for other organisms when, for example, ontogenetic changes in the expression of individual cues may hamper their usefulness as kin recognition cues.

Male-derived cuticular hydrocarbons signal sperm competition intensity and affect ejaculate expenditure in crickets

Female sexual promiscuity can have significant effects on male mating decisions because it increases the intensity of competition between ejaculates for fertilization. Because sperm production is costly, males that can detect multiple matings by females and allocate sperm strategically will have an obvious fitness advantage. The presence of rival males is widely recognized as a cue used by males to assess sperm competition. However, for species in which males neither congregate around nor guard females, other more cryptic cues might be involved. Here, we demonstrate unprecedented levels of sperm competition assessment by males, which is mediated via the use of chemical cues. Using the cricket Teleogryllus oceanicus, we manipulated male perception of sperm competition by experimentally coating live unmated females with cuticular compounds extracted from males. We found that males adjusted their ejaculate allocation in response to these compounds: the viability of sperm contained within a male's ejaculate decreased as the number of male extracts applied to his virgin female partner was increased. We further show that males do not respond to the relative concentration of male compounds present on females, but rather to the number of distinct signature odours of individual males. Our results conform to sperm competition theory, and show for the first time, to our knowledge, that males can detect different intensities of sperm competition by using distinct chemical cues of individual males present on females.

Use of chemical cues during shell fights in the hermit crab Pagurus bernhardus

AbstractChemical communication is likely to play an important role during agonistic encounters in aquatic crustaceans but the use of chemical signals is difficult to observe. An alternative approach to direct observation is to collect water that has contained fighting animals and then expose a focal animal of the same species to the cue water and monitor its behaviour. Here we investigate the possibility of the use of chemical cues during 'shell fights' in the hermit crab Pagurus bernhardus. Focal crabs exposed to the fighting cue spent more time withdrawn into their gastropod shell, less time on locomotion and less time searching for food than did those exposed to cues from non-fighting hermit crabs or those treated with plain sea water. At the end of the observation period we used a novel stimulus to induce a startle response in order to probe the focal crab's motivational state for this exploratory behaviour. Those exposed to the fighting cue water took longer to recover than crabs in the other groups, indicating that their motivation was lower. These findings provide clear evidence that chemical cues are a feature of these contests.

Use of chemical cues in detection of conspecific predators and prey by newts, Notophthalmus viridescens

Detection of heterospecific predators and prey via chemical cues is well known, but only a few studies have examined the potential for such discrimination in cannibalistic systems. In newts, Notophthalmus viridescens, adults are opportunistic predators of conspecific larvae. I used a laboratory bioassay to determine whether larvae and adults distinguish between chemical stimuli from members of the different age classes. Larvae distinguished between chemical stimuli from larvae and adults by decreasing their activity only following exposure to stimuli from adults. Decreased activity is consistent with an antipredator response in many prey species, including larval newts. In contrast, adults increased their activity and increased time spent in open areas in response to stimuli from larvae, but not to stimuli from adults. Increased activity is consistent with a feeding response; adults also showed increased activity and increased time in open areas in response to chemical stimuli from familiar heterospecific prey (brine shrimp). The proximate cue that allowed the newts to distinguish between the different age classes is not associated with short-term dietary differences because all stimulus animals were fed the same prey. Stimulus “strength” was controlled by diluting the stimulus solutions according to the volume of the stimulus animal. Therefore, there appear to be intrinsic differences in the chemical signatures of larval and adult newts.

Homing ability and sensitivity to the geomagnetic field in the alpine newt, Triturus alpestris

Triturus alpestris has been found to be adept at homing, and previous studies have found that its orientation behaviour during breeding migration can be explained, at least in part, by the use of olfactory cues from the breeding pond. Nonetheless, the use of chemical cues from the pond probably does not support a guidance strategy when the newts are far from the pond. Hence, T. alpestris may rely on other orientation cues. In this study, alpine newts were tested in a circular arena to determine the sensory cues used to locate breeding ponds. Animals were collected from a permanent pond situated in northern Spain, taken to the experimental site 9020 m distant, and tested for orientation under a variety of conditions (i.e., orientation under a clear night sky, orientation under dark conditions, and orientation under a clear night sky in the presence of an altered geomagnetic field). The possibility of a non-homing directional bias was also tested. Newts chose a compass course in the direction of their breeding pond only when the ambient geomagnetic field and the celestial cues were simultaneously available. Conversely, animals failed to orient only when celestial cues or the geomagnetic field were the sole orientation cues available.

Potential use of chemical cues for colony-mate recognition in the big brown bat, Eptesicus fuscus.

Bats should benefit from recognition of their roost-mates when colonies form stable social units that persist over time. We used Y-maze experiments and gas chromatography-olfactometry (GC-O) to evaluate whether female big brown bats Eptesicus fuscus (Chiroptera: Vespertilionidae) use chemical cues to distinguish among conspecifics. In dual-choice Y-maze experiments, females chose the scent of another female from their own roost over a conspecific female from a different roost in a majority of trials. Analysis of total body odors using GC-O suggests that individuals from a given colony may share a more common odor signature with roost-mates than with non-roost-mate conspecifics. Using four principle components derived from 15 odor variables, discriminant function analysis correctly assigned most individuals to the correct colony.

Homing in wood ants, Formica japonica: use of the skyline panorama.

Homeward orientation was studied in wood ants Formica japonica that, while foraging, shuttled back and forth along a 7.9m route between the nest and a feeding site located on a wide terrace platform surrounded by a conspicuous landmark panorama. The return runs of the ants were amazingly straight, not only in the controls (starting at the feeding site) but also in ants displaced for various distances to the left and right of the feeding site. These courses, however, were oriented neither parallel to the predisplacement courses nor directly towards the nest. This result excludes the use of chemical cues and celestial compass cues. Furthermore, the nest itself, or some object close to it, could not have served as a beacon. The extensions of the homeward paths taken by ants that had been displaced to various release sites up to 11m sideways from the training route intersected at a point far (approximately 13m) behind the nest. This result suggests that the ants used distant landmarks seen by them in their frontal fields of view. To test this hypothesis, the distant landmark panorama was concealed by an opaque sheet mounted at right angles to the normal return route of the ants and extending up to different elevations. Shielding the lower part of the landmark panorama had no effect on the homeward paths. However, when the screen was mounted in such a way that the ants could only see the top skyline, represented by the upper edges of a line of trees, for part of their return run, it was only during these parts that their path was oriented in the homeward direction. When, during the course of displacement experiments, the ants were deprived of their familiar skyline panorama, they moved in their home direction only for an extremely short distance (0.1-0.4m rather than the usual 7.9m) and then started a systematic search programme. Hence, in the present context, skylight information is not used, at least not extensively. Instead, ants use the distant skyline as a navigational guidemark.

Learned Recognition of Intraspecific Predators in Larval Long‐Toed Salamanders Ambystoma macrodactylum

The ability of prey to detect predators and respond accordingly is critical to their survival. The use of chemical cues by animals in predator detection has been widely documented. In many cases, predator recognition is facilitated by the release of alarm cues from conspecific victims. Alarm cues elicit anti‐predator behavior in many species, which can reduce their risk of being attacked. It has been previously demonstrated that adult long‐toed salamanders, Ambystoma macrodactylum, exhibit an alarm response to chemical cues from injured conspecifics. However, whether this response exists in the larval stage of this species and whether it is an innate or a learned condition is unknown. In the current study, we examined the alarm response of naïve (i.e. lab‐reared) larval long‐toed salamanders. We conducted a series of behavioral trials during which we quantified the level of activity and spatial avoidance of hungry and satiated focal larvae to water conditioned by an injured conspecific, a cannibal that had recently been fed a conspecific or a non‐cannibal that was recently fed a diet of Tubifex worms. Focal larvae neither reduced their activity nor spatially avoided the area of the stimulus in either treatment when satiated, and exhibited increased activity towards the cannibal stimulus when hungry. We regard this latter behavior as a feeding response. Together these results suggest that an anti‐predator response to injured conspecifics and to cannibalistic conspecifics is absent in naïve larvae.Previous studies have shown that experienced wild captured salamanders do show a response to cannibalistic conspecifics. Therefore, we conducted an additional experiment examining whether larvae can learn to exhibit anti‐predator behavior in response to cues from cannibalized conspecifics. We exposed larvae to visual, chemical and tactile cues of stimulus animals that were actively foraging on conspecifics (experienced) or a diet of Tubifex (naïve treatment). In subsequent behavioral treatments, experienced larvae significantly reduced their activity compared to naive larvae in response to chemical cues of cannibals that had recently consumed conspecifics. We suggest that this behavior is a response to alarm cues released by consumed conspecifics that may have labeled the cannibal. Furthermore, over time, interactions with cannibals may cause potential prey larvae to learn to avoid cannibals regardless of their recent diet.