Odor Signals Research Articles

Molecular Profiling of the Drosophila Antenna Reveals Conserved Genes Underlying Olfaction in Insects.

Repellent odors are widely used to prevent insect-borne diseases, making it imperative to identify the conserved molecular underpinnings of their olfactory systems. Currently, little is known about the molecules supporting odor signaling beyond the odor receptors themselves. Most known molecules function in one of two classes of olfactory sensilla, single-walled or double-walled, which have differing morphology and odor response profiles. Here, we took two approaches to discover novel genes that contribute to insect olfaction in the periphery. We transcriptionally profiled Drosophila melanogaster amos mutants that lack trichoid and basiconic sensilla, the single-walled sensilla in this species. This revealed 187 genes whose expression is enriched in these sensilla, including pickpocket ion channels and neuromodulator GPCRs that could mediate signaling pathways unique to single-walled sensilla. For our second approach, we computationally identified 141 antennal-enriched (AE) genes that are more than ten times as abundant in D. melanogaster antennae as in other tissues or whole-body extracts, and are thus likely to play a role in olfaction. We identified unambiguous orthologs of AE genes in the genomes of four distantly related insect species, and most identified orthologs were expressed in the antenna of these species. Further analysis revealed that nearly half of the 141 AE genes are localized specifically to either single or double-walled sensilla. Functional annotation suggests the AE genes include signaling molecules and enzymes that could be involved in odorant degradation. Together, these two resources provide a foundation for future studies investigating conserved mechanisms of odor signaling.

Antennae-specific carboxylesterase genes from Indian meal moth: Identification, tissue distribution and the response to semiochemicals

In the olfactory recognition system of insects, carboxylesterases (CXEs) in insect antennae play crucial roles in inactivating the chemical signals. Identification of antennae-specific CXEs provides the molecular basis of odorant degradation and signal inactivation in insects through which potential pest control strategies can be further studied. Although pheromone-based attract-and-kill has been proved to be an effective method to monitor and control Plodia interpunctella, very few reports have focused on the degradation of pheromone as well as the host volatiles and environmental odorants. In the present study, we identified 28 candidate P. interpunctella carboxylesterases (PintCXEs) from our previously reported antennal transcriptome data. Almost all full-length PintCXEs displayed the characteristics of conserved motifs found in other insect CXEs, such as the oxyanion hole residues (Gly-Gly-Ala), the catalytic triad (Ser-Glu-His), and the conserved pentapeptide Gly-X-Ser-X-Gly. Through phylogenetic analysis, two major groups of PintCXEs were identified, including the moth antennal esterases and mitochondrial and cytosolic esterases. Further gene expression profiling revealed that 13 PintCXEs (PintCXE2, PintCXE4, PintCXE9, PintCXE11, PintCXE13, PintCXE15-21, PintCXE25) were highly expressed in antennae, indicating that these PintCXEs were potentially involved in odorant degradation. Among these PintCXEs, PintCXE2, PintCXE4, PintCXE11-12, PintCXE15 and PintCXE17 were male-specific, while PintCXE9, PintCXE13, PintCXE20 and PintCXE25 were highly expressed in female antennae compared with the male antennae. The expressions of PintCXE19 and PintCXE25 were significantly up-regulated by ester treatment, suggesting that they could be involved in degradation of sex pheromone and environment esters. Our results lay a solid foundation for better understanding the olfactory inactivation system of insects.

Palatability of Bile Substances for Fish

Palatability of sodium cholate (10–1 M), sodium taurocholate (10–1 M), and dehydrocholic acid (0.5 × 10–3 M) for Mexican cavefish Astyanax fasciatus (blind form), silver dollar Metynnis argenteus, Nile tilapia Oreochromis niloticus, green swordtail Xiphophorus hellerii, and roach Rutilus rutilus was assessed. All substances have a significant taste effect, but the reaction of fishes to their taste is different and the responses to the same substance were different. Taste attractiveness for bile substances (sodium taurocholate, dehydrocholic acid) was found only in Mexican cavefish, which allows it to feed on specific food (bat guano) available in cave reservoirs where other food resources are extremely insignificant. For the rest of the fishes, bile substances had an inert or aversive taste, which can prevent coprophagy and contribute to long-term preservation of feces in the environment, which are an important source of odor signals for fish. It has been proposed to consider bile substances as important chemical regulators of fish relationships in aquatic communities.

Front-end Weber-Fechner gain control enhances the fidelity of combinatorial odor coding.

We showed previously (Gorur-Shandilya et al., 2017) that Drosophila olfactory receptor neurons (ORNs) expressing the co-receptor Orco scale their gain inversely with mean odor intensity according to Weber-Fechner's law. Here, we show that this front-end adaptation promotes the reconstruction of odor identity from dynamic odor signals, even in the presence of confounding background odors and rapid intensity fluctuations. These enhancements are further aided by known downstream transformations in the antennal lobe and mushroom body. Our results, which are applicable to various odor classification and reconstruction schemes, stem from the fact that this adaptation mechanism is not intrinsic to the identity of the receptor involved. Instead, a feedback mechanism adjusts receptor sensitivity based on the activity of the receptor-Orco complex, according to Weber-Fechner's law. Thus, a common scaling of the gain across Orco-expressing ORNs may be a key feature of ORN adaptation that helps preserve combinatorial odor codes in naturalistic landscapes.

Associations between olfactory pathway gene methylation marks, obesity features and dietary intakes

BackgroundOlfaction is an important sense influencing food preferences, appetite, and eating behaviors. This hypothesis-driven study aimed to assess associations between olfactory pathway gene methylation signatures, obesity features, and dietary intakes.MethodsA nutriepigenomic analysis was conducted in 474 adults from the Methyl Epigenome Network Association (MENA) project. Anthropometric measurements, clinical data, and serum metabolic profiles of the study population were obtained from structured databases of the MENA cohorts. Habitual dietary intake was assessed using a validated semiquantitative food frequency questionnaire. DNA methylation was measured in circulating white blood cells by microarray (Infinium Human Methylation 450 K BeadChips). FDR values (p < 0.0001) were used to select those CpGs that showed the best correlation with body mass index (BMI) and waist circumference (WC). Pathway analyses involving the characterization of genes involved in the olfactory transduction system were performed using KEGG and pathDIP reference databases.ResultsOverall, 15 CpG sites at olfactory pathway genes were associated with BMI (p < 0.0001) and WC (p < 0.0001) after adjustments for potential confounding factors. Together, methylation levels at the15 CpG sites accounted for 22% and 20% of the variability in BMI and WC (r2 = 0.219, p < 0.001, and r2 = 0.204, p < 0.001, respectively). These genes encompassed olfactory receptors (OR4D2, OR51A7, OR2T34, and OR2Y1) and several downstream signaling molecules (SLC8A1, ANO2, PDE2A, CALML3, GNG7, CALML6, PRKG1, and CAMK2D), which significantly regulated odor detection and signal transduction processes within the complete olfactory cascade, as revealed by pathway enrichment analyses (p = 1.94 × 10–10). Moreover, OR4D2 and OR2Y1 gene methylation patterns strongly correlated with daily intakes of total energy (p < 0.0001), carbohydrates (p < 0.0001), protein (p < 0.0001), and fat (p < 0.0001).ConclusionsThe results of this study suggest novel relationships between olfactory pathway gene methylation signatures, obesity indices, and dietary intakes.

The Olfactory System of Zebrafish as a Model for the Study of Neurotoxicity and Injury: Implications for Neuroplasticity and Disease.

The olfactory system, composed of the olfactory organs and the olfactory bulb, allows organisms to interact with their environment and through the detection of odor signals. Olfaction mediates behaviors pivotal for survival, such as feeding, mating, social behavior, and danger assessment. The olfactory organs are directly exposed to the milieu, and thus are particularly vulnerable to damage by environmental pollutants and toxicants, such as heavy metals, pesticides, and surfactants, among others. Given the widespread occurrence of olfactory toxicants, there is a pressing need to understand the effects of these harmful compounds on olfactory function. Zebrafish (Danio rerio) is a valuable model for studying human physiology, disease, and toxicity. Additionally, the anatomical components of the zebrafish olfactory system are similar to those of other vertebrates, and they present a remarkable degree of regeneration and neuroplasticity, making it an ideal model for the study of regeneration, reorganization and repair mechanisms following olfactory toxicant exposure. In this review, we focus on (1) the anatomical, morphological, and functional organization of the olfactory system of zebrafish; (2) the adverse effects of olfactory toxicants and injury to the olfactory organ; and (3) remodeling and repair neuroplasticity mechanisms following injury and degeneration by olfactory toxicant exposure.

The role of male forearm crust odour in fringe-lipped bats (Trachops cirrhosus)

Abstract Chemical signals can play important roles in communication, and this is especially true for social mammals such as bats. Male fringe-lipped bats (Trachops cirrhosus) produce an odorous substance on their forearm, called forearm crust. Only adult males with descended testes produce forearm crust. This is thus a sexually dimorphic odour, which suggests that it is a sexually selected trait. Since males lack a specific gland on their forearm we sought to identify the source of the forearm crust. Our second aim was to test female and male preference for this trait. Based on gas chromatography and mass spectrometry analyses we tentatively identified several compounds that were exclusive to the forearm crust. We found that the chemical composition of the forearm crust was not mainly composed of chest gland secretions or urine. We conducted a y-maze odour preference experiment to test whether adult females and reproductive males preferred the odour of a male with forearm crust compared to the odour of a male without forearm crust. Contrary to our prediction we found that females did not approach the scent of a male with forearm crust more frequently than the scent of male without forearm crust. We found that males with forearm crust, however, preferred the odour of males without forearm crust. Overall our results suggest that in this Neotropical bat species, reproductive males could use odorous signals in the forearm crust to mediate interactions between reproductive males and potentially avoid costly competition for mates or aggression. In sum, our results shed light on the role that chemical mediated signals can play in mammalian social behaviour.

Controlling and measuring dynamic odorant stimuli in the laboratory.

Animals experience complex odorant stimuli that vary widely in composition, intensity and temporal properties. However, stimuli used to study olfaction in the laboratory are much simpler. This mismatch arises from the challenges in measuring and controlling them precisely and accurately. Even simple pulses can have diverse kinetics that depend on their molecular identity. Here, we introduce a model that describes how stimulus kinetics depend on the molecular identity of the odorant and the geometry of the delivery system. We describe methods to deliver dynamic odorant stimuli of several types, including broadly distributed stimuli that reproduce some of the statistics of naturalistic plumes, in a reproducible and precise manner. Finally, we introduce a method to calibrate a photo-ionization detector to any odorant it can detect, using no additional components. Our approaches are affordable and flexible and can be used to advance our understanding of how olfactory neurons encode real-world odor signals.

Elevated CO2 impairs olfactory-mediated neural and behavioral responses and gene expression in ocean-phase coho salmon (Oncorhynchus kisutch).

Elevated concentrations of CO2 in seawater can disrupt numerous sensory systems in marine fish. This is of particular concern for Pacific salmon because they rely on olfaction during all aspects of their life including during their homing migrations from the ocean back to their natal streams. We investigated the effects of elevated seawater CO2 on coho salmon (Oncorhynchus kisutch) olfactory-mediated behavior, neural signaling, and gene expression within the peripheral and central olfactory system. Ocean-phase coho salmon were exposed to three levels of CO2 , ranging from those currently found in ambient marine water to projected future levels. Juvenile coho salmon exposed to elevated CO2 levels for 2weeks no longer avoided a skin extract odor that elicited avoidance responses in coho salmon maintained in ambient CO2 seawater. Exposure to these elevated CO2 levels did not alter odor signaling in the olfactory epithelium, but did induce significant changes in signaling within the olfactory bulb. RNA-Seq analysis of olfactory tissues revealed extensive disruption in expression of genes involved in neuronal signaling within the olfactory bulb of salmon exposed to elevated CO2 , with lesser impacts on gene expression in the olfactory rosettes. The disruption in olfactory bulb gene pathways included genes associated with GABA signaling and maintenance of ion balance within bulbar neurons. Our results indicate that ocean-phase coho salmon exposed to elevated CO2 can experience significant behavioral impairments likely driven by alteration in higher-order neural signal processing within the olfactory bulb. Our study demonstrates that anadromous fish such as salmon may share a sensitivity to rising CO2 levels with obligate marine species suggesting a more wide-scale ecological impact of ocean acidification.

Variance adaptation in navigational decision making.

Sensory systems relay information about the world to the brain, which enacts behaviors through motor outputs. To maximize information transmission, sensory systems discard redundant information through adaptation to the mean and variance of the environment. The behavioral consequences of sensory adaptation to environmental variance have been largely unexplored. Here, we study how larval fruit flies adapt sensory-motor computations underlying navigation to changes in the variance of visual and olfactory inputs. We show that variance adaptation can be characterized by rescaling of the sensory input and that for both visual and olfactory inputs, the temporal dynamics of adaptation are consistent with optimal variance estimation. In multisensory contexts, larvae adapt independently to variance in each sense, and portions of the navigational pathway encoding mixed odor and light signals are also capable of variance adaptation. Our results suggest multiplication as a mechanism for odor-light integration.

Second messenger molecules have a limited spread in olfactory cilia.

Odorants are detected by olfactory receptors on the sensory cilia of olfactory receptor cells (ORCs). These cylindrical cilia have a diameters of 100-200 nm, within which the components required for signal transduction by the adenylyl cyclase-cAMP system are located. The kinetics of odorant responses are determined by the lifetimes of active proteins as well as the production, diffusion, and extrusion/degradation of second messenger molecules (cAMP and Ca2+). However, there is limited information about the molecular kinetics of ORC responses, mostly because of the technical limitations involved in studying such narrow spaces and fine structures. In this study, using a combination of electrophysiology, photolysis of caged substances, and spot UV laser stimulation, we show that second messenger molecules work only in the vicinity of their site of generation in the olfactory cilia. Such limited spreading clearly explains a unique feature of ORCs, namely, the integer multiple of unitary events that they display in low Ca2+ conditions. Although the small ORC uses cAMP and Ca2+ for various functions in different regions of the cell, these substances seem to operate only in the compartment that has been activated by the appropriate stimulus. We also show that these substances remain in the same vicinity for a long time. This enables the ORC to amplify the odorant signal and extend the lifetime of Ca2+-dependent adaptation. Cytoplasmic buffers and extrusion/degradation systems seem to play a crucial role in limiting molecular spreading. In addition, binding sites on the cytoplasmic surface of the plasma membrane may limit molecular diffusion in such a narrow space because of the high surface/volume ratio. Such efficient energy conversion may also be broadly used in other biological systems that have not yet been subjected to systematic experiments.

Kompleksitas Obyek dan Running-Wheel Mempengaruhi Novel Object Recognition Test pada Mencit (Mus musculus)

This research aimed to confirm the tendency of mice to novel object, effect of exercise (in running-wheel) toward memory of mice and to test tendency of mice in avoiding predator signal in novel object. Novel object recognition test (NORT) used to test the memory the day after acquisition phase (NORT I) and memory one week after exercise was given (running-wheel) (NORT II). The result showed that there was no tendency of mice in exploring toward novel object in both NORT I and NORT II. This might happen because the complexity of familiar object higher than novel object, so the familiar object could accommodate more activities. Exercise using running-wheel in mice had an effect on memory, it could be seen in decreasing duration of object exploration time from NORT I to NORT II. There was no tendency in avoiding predator’s signal on novel object which was attached by urine addition (odor signal).

Transcriptome characterization and gene expression analysis related to chemoreception in Trichogramma chilonis, an egg parasitoid

Chemoreception is critical for the survival of insects. Insects have a variety of behavioral responses, such as mating, host searching and ovipositing, in response to different odor signals detected in their living environment. Trichogramma chilonis, an egg parasitoid, acts as an efficient and effective biocontrol reagent for many agricultural and forestry insect pests in many parts of China. However, little is known about the molecular mechanism of the olfaction-evoked behavior in T. chilonis. In the present study, we conducted transcriptome profiling analysis of T. chilonis based on the Illumina high-throughput sequencing platform in order to explore differences of chemoreception between male and female T. chilonis. In this study, a total of 85 chemosensory genes were identified from transcriptomic data, including 45 odorant receptors (ORs), 22 odorant binding proteins (OBPs), 14 ionotropic receptors (IRs), 2 sensory neuron membrane proteins (SNMPs) and 2 chemosensory proteins (CSPs). From the analysis of the transcriptome, most of the candidate olfactory genes had similar expression levels in males and females, including a few OR and OBP genes (TchiOR38, TchiOR39, TchiOR40, TchiOR41, TchiOR42, TchiOR43, TchiOR44, TchiOR45, TchiOBP1, TchiOBP4, TchiOBP10, TchiOBP12, TchiOBP18 and TchiOBP19) which showed male-biased expression. Some annotated unigenes were chosen randomly to have qRT-PCR, which verified the correctness of analysis of transcriptome in T. chilonis. This is the first study to obtain and identify candidate genes related to chemoreception in T. chilonis. Our work lays a solid foundation for related future research on the chemosensory system of T. chilonis at the molecular level and helps advance the use of T. chilonis as biological control agents.

Cell-specific plasticity associated with integrative memory of triple sensory signals in the barrel cortex.

Neuronal plasticity occurs in associative memory. Associative memory cells are recruited for the integration and storage of associated signals. The coordinated refinements and interactions of associative memory cells including glutamatergic and GABAergic neurons remain elusive, which we have examined in a mouse model of associative learning. Paired olfaction, tail and whisker stimulations lead to odorant-induced and tail-induced whisker motions alongside whisker-induced whisker motion. In mice that show this cross-modal associative memory, barrel cortical glutamatergic and GABAergic neurons are recruited to encode the newly learned odor and tail signals alongside the innate whisker signal. These glutamatergic neurons are functionally upregulated, and GABAergic neurons are refined in a homeostatic manner. The mutual innervations between these glutamatergic and GABAergic neurons are upregulated. Therefore, the co-activations of sensory cortices by pairing the input signals recruit their glutamatergic and GABAergic neurons to be associative memory cells, which undergo coordinated refinement among glutamatergic and GABAergic neurons as well as homeostatic plasticity among subcellular compartments in order to drive these cells toward the optimal state for the integrative storage of associated signals.

Evolution of Caste-Specific Chemical Profiles in Halictid Bees.

Chemical communication is crucial for the maintenance of colony organization in eusocial insects and chemical signals are known to mediate important aspects of their social life, including the regulation of reproduction. Sociality is therefore hypothesized to be accompanied by an increase in the complexity of chemical communication. However, little is known about the evolution of odor signals at the transition from solitary living to eusociality. Halictid bees are especially suitable models to study this question as they exhibit considerable variability in social behavior. Here we investigated whether the dissimilarities in cuticle chemical signals in females of different castes and life stages reflect the level of social complexity across halictid bee species. Our hypothesis was that species with a higher social behavior ergo obligate eusocial species possess a more distinct chemical profile between castes or female life stages. We analyzed cuticular chemical profiles of foundresses, breeding females and workers of ancestrally solitary species, facultative and obligate eusocial halictid species. We also tested whether social complexity was associated with a higher investment in chemical signals. Our results revealed higher chemical dissimilarity between castes in obligate than in facultative eusocial species, especially regarding macrocyclic lactones, which were the single common compound class overproduced in queens compared with workers. Chemical dissimilarities were independent of differences in ovarian status in obligate eusocial species but were dependent on ovarian status in facultative eusocial species, which we discuss in an evolutionary framework.

Opening the chemosensory world of the lobster, Homarus americanus

The natural history of the American lobster, Homarus americanus H. Milne-Edwards, 1837, was described in detail as part of the general interest in marine biology in the late 19th century. A half-century ago, lobsters gained prominence in the biological analysis of underwater chemical sensing, using neurobiological, behavioral, and ecological approaches. Lobsters made us recognize different chemical sensing organs, each with their unique signal-filtering properties and behavioral functions, and they showed how they generate and control information currents for both odor dispersal and reception. This led to better understanding of the constraints that fluid motion places on odor signal analysis and sensor design. This, in turn, spurred construction of a lobster-inspired electronic nose to measure the temporal resolution of chemoreceptor organs used in odor plume analysis and tracking. Simultaneously, long-term field and naturalistic tank observations revealed their social structure involving sheltering, dominance fights, individual recognition by urine signals, courtship displays, cohabitation, and mating behavior. While most investigations focused on chemical signals, flow sensors were analyzed as part of antennule flicking and odor-flow coincidence detection. Mechanoreception plays an important role in smelling and tasting. Lobster vision contributes to opponent size estimates and recognition. Multisensory analysis will become increasingly important as is the chemical identification of the signals. Lobsters remain significant contributors to underwater sensory biology, influencing many other model systems, including other crustaceans, mollusks, sharks, and reef fish larvae. It has always been my privilege to work with so many inspiring students and colleagues.

Contribution of DA Signaling to Appetitive Odor Perception in a Drosophila Model

Understanding cognitive processes that translate chemically diverse olfactory stimuli to specific appetitive drives remains challenging. We have shown that food-related odors arouse impulsive-like feeding of food media that are palatable and readily accessible in well-nourished Drosophila larvae. Here we provide evidence that two assemblies of four dopamine (DA) neurons, one per brain hemisphere, contribute to perceptual processing of the qualitative and quantitative attributes of food scents. These DA neurons receive neural representations of chemically diverse food-related odors, and their combined neuronal activities become increasingly important as the chemical complexity of an appetizing odor stimulus increases. Furthermore, in each assembly of DA neurons, integrated odor signals are transformed to one-dimensional DA outputs that have no intrinsic reward values. Finally, a genetic analysis has revealed a D1-type DA receptor (Dop1R1)-gated mechanism in neuropeptide Y-like neurons that assigns appetitive significance to selected DA outputs. Our findings suggest that fly larvae provide a useful platform for elucidation of molecular and circuit mechanisms underlying cognitive processing of olfactory and possibly other sensory cues.

Divergence in male sexual odor signal and genetics across populations of the red mason bee, Osmia bicornis, in Europe.

In some insect species, females may base their choice for a suitable mate on male odor. In the red mason bee, Osmia bicornis, female choice is based on a male’s odor bouquet as well as its thorax vibrations, and its relatedness to the female, a putative form of optimal outbreeding. Interestingly, O. bicornis can be found as two distinct color morphs in Europe, which are thought to represent subspecies and between which we hypothesize that female discrimination may be particularly marked. Here we investigated (i) if these two colors morphs do indeed represent distinct, reproductively differentiated populations, (ii) how odor bouquets of male O. bicornis vary within and between populations, and (iii) whether variation in male odor correlates with genetic distance, which might represent a cue by which females could optimally outbreed. Using GC and GC-MS analysis of male odors and microsatellite analysis of males and females from 9 populations, we show that, in Denmark, an area of subspecies sympatry, the two color morphs at any one site do not differ, either in odor bouquet or in population genetic differentiation. Yet populations across Europe are distinct in their odor profile as well as being genetically differentiated. Odor differences do not, however, mirror genetic differentiation between populations. We hypothesize that populations from Germany, England and Denmark may be under sexual selection through female choice for local odor profiles, which are not related to color morph though which could ultimately lead to population divergence and speciation.

History dependence in insect flight decisions during odor tracking.

Natural decision-making often involves extended decision sequences in response to variable stimuli with complex structure. As an example, many animals follow odor plumes to locate food sources or mates, but turbulence breaks up the advected odor signal into intermittent filaments and puffs. This scenario provides an opportunity to ask how animals use sparse, instantaneous, and stochastic signal encounters to generate goal-oriented behavioral sequences. Here we examined the trajectories of flying fruit flies (Drosophila melanogaster) and mosquitoes (Aedes aegypti) navigating in controlled plumes of attractive odorants. While it is known that mean odor-triggered flight responses are dominated by upwind turns, individual responses are highly variable. We asked whether deviations from mean responses depended on specific features of odor encounters, and found that odor-triggered turns were slightly but significantly modulated by two features of odor encounters. First, encounters with higher concentrations triggered stronger upwind turns. Second, encounters occurring later in a sequence triggered weaker upwind turns. To contextualize the latter history dependence theoretically, we examined trajectories simulated from three normative tracking strategies. We found that neither a purely reactive strategy nor a strategy in which the tracker learned the plume centerline over time captured the observed history dependence. In contrast, “infotaxis”, in which flight decisions maximized expected information gain about source location, exhibited a history dependence aligned in sign with the data, though much larger in magnitude. These findings suggest that while true plume tracking is dominated by a reactive odor response it might also involve a history-dependent modulation of responses consistent with the accumulation of information about a source over multi-encounter timescales. This suggests that short-term memory processes modulating decision sequences may play a role in natural plume tracking.

Tracking Odorant Plumes.

Chemical signals are primarily distributed throughout aquatic environments by processes that are affected by turbulence. Turbulence continually stirs and mixes chemical odorants into complex, filamentous structures that are sampled by organisms. These odorant signals are critical for survival and/or reproductive success of most aquatic animals, and the time varying spatial structure of velocity and concentration offers valuable guidance cues while navigating in a plume. Two separate techniques are described to simultaneously measure a turbulent odor plume on a scale relevant to the chemosensors and mechanosensors located along the antennules of aquatic organisms. The first, planar laser induced fluorescence (PLIF), is used to quantify odorant concentrations, while the second, particle image velocimetry (PIV), is used to measure turbulent fluid velocities.