Snake Tongue Flicking Behavior: Clues to Vomeronasal System Functions

Author(s):  
Mimi Halpern ◽  
John L. Kubie
1996 ◽  
Vol 17 (3) ◽  
pp. 217-231 ◽  
Author(s):  
Christopher S. DePerno ◽  
William E. Cooper ◽  
Laura J. Steele

AbstractPoststrike elevation in tongue-flicking rate (PETF) and strike-induced chemosensory searching (SICS) were assessed experimentally in two species of gekkonoid lizards belonging to families differing in foraging mode. PETF is an increase in rate of lingual protrusions after a prey item has been bitten and escapes or is removed from the mouth of a squamate reptile, whereas SICS is PETF combined with locomotory searching behavior. Eublepharis mucularius, the leopard gecko, is an actively, albeit slowly, foraging eublepharid. This species exhibited PETF for a duration of about five minutes based on total lingual protrusions. Labial-licks were initially much more frequent than tongue-flicks. A substantial increase in movement occurred during minutes 5-8, hinting that SICS might be present, but was not quite significant. SICS is likely present, as in other actively foraging lizards, but was not conclusively demonstrated. Handling the lizards induced increased locomotion in both the experimental condition and a control condition, presumably accounting for the apparent delay in onset of increased movement. The tokay gecko, Gekko gecko, a gekkonid ambush forager, performed no tongue-flicks, but exhibited PETF based on labial-licks during the first minute. SICS was absent. These findings support the hypothesis that SICS is absent in ambush foraging lizards, which do not use the lingual-vomeronasal system to search for prey. They are suggestive, but equivocal regarding the hypothesis that SICS is present in actively foraging lizards that exhibit lingually mediated prey chemical discrimination. The finding of PETF in G. gecko suggests that this species and several iguanians previously found to increase rates of labial-licking after biting prey may be able to detect prey chemicals.


2007 ◽  
Vol 85 (5) ◽  
pp. 619-625 ◽  
Author(s):  
William E. Cooper, ◽  
Stephen Secor

Squamate reptiles use the lingual–vomeronasal system to identify food using only chemical cues. In lizards, most of which are dietary generalists that consume a wide variety of arthropods and other small animals, correlated evolution has occurred between addition of plants to the diet and responsiveness to plant chemical cues. In snakes, many of which are dietary specialists, several studies have detected differences in response strength among populations that correspond to the importance of prey types in different geographic locations. In one species of Thamnophis Fitzinger, 1843, such variation in responsiveness has been demonstrated to have a genetic basis. We studied tongue-flicking and biting responses to chemical cues from a range of potential prey types by nine ingestively naive hatchlings of the eastern hog-nosed snake ( Heterodon platirhinos Latreille in Sonnini and Latreille, 1801), which is an extreme toad specialist that less frequently eats other anurans. The snakes responded most strongly to chemical cues from the southern toad ( Bufo terrestris (Bonnaterre, 1789)), as indicated by significantly greater tongue-flick rate. Only two individuals bit in response to chemicals cues, both to the toad cues. Elevated tongue-flick rates were also elicited by chemical cues from the green frog ( Rana clamitans Latreille in Sonnini de Manoncourt and Latreille, 1801), but the mean rate for frog cues was less than for toad cues. Responses to other potential prey types did not differ from those of the control stimuli. Our findings are consistent with those of several other investigators in showing close correspondence between the inclusion and importance of dietary items and the intensity of chemosensory investigation in snakes. Studies of diverse dietary specialists are needed to establish the generality of this relationship in snakes and to demonstrate that diet and chemosensory responses to food cues coevolve.


2011 ◽  
Vol 8 (2) ◽  
pp. 183-185 ◽  
Author(s):  
R. Shine ◽  
R. T. Mason

Most reptile sex pheromones so far described are lipid molecules too large to diffuse through the air; instead, they are detected via direct contact (tongue-flicking) with another animal's body or substrate-deposited trails, using the vomeronasal system. The only non-lipid pheromone reported in snakes involves courtship termination in red-sided gartersnakes ( Thamnophis sirtalis parietalis ): males that encounter copulatory fluids cease courtship, presumably reflecting the futility of courting an already-mating female. Our field experiments at a communal den in Manitoba show that this pheromone can work via olfaction: courtship is terminated by exposure to airborne scents from mating conspecifics, and does not require direct contact (tongue-flicking). Hence, the sexual behaviour of reptiles can be affected by airborne as well as substrate-bound pheromones.


2012 ◽  
Vol 287 (40) ◽  
pp. 33644-33655 ◽  
Author(s):  
Bernd Bufe ◽  
Timo Schumann ◽  
Frank Zufall

1992 ◽  
Vol 70 (10) ◽  
pp. 1886-1896 ◽  
Author(s):  
Véronique Goosse ◽  
Vincent L. Bels

High-speed cinematography (100 frames/s) was used to allow quantitative analysis of the kinematic profiles of tongue and jaw displacements during chemosensory activities in the scleroglossan lizard Lacerta viridis. The types of tongue flicking were simple downward extensions (SDE), single oscillations (SOC), and submultiple oscillations (SMOC) of the tongue out of the mouth. The SMOC type involves a downward or upward movement of the tongue performed before a typical oscillation and it is therefore suggested that this is an intermediate category of flick between the typical SOC and MOC of lizards. Closing and opening of the mouth in SDE, SOC, and SMOC cycles may or may not be separated by a stationary stage during which the jaws are held open at a constant gape. The duration of this stationary interval increases from SDE to SMOC. Gape cycles do not show any division into slow and fast stages. The gape is produced largely by depression of the lower jaw; the upper jaw is slightly elevated by protrusion of the tongue. Patterns of correlation of kinematic variables depicting jaw and tongue movements differed between SDE, SOC, and SMOC. A principal component analysis shows that the three flick types overlap in a multivariate space constructed from the kinematic variables depicting jaw and tongue displacements. Overlap between SOC and SMOC categories is greater than that between SOC, SMOC, and SDE categories. The kinematic patterns of tongue displacement during SMOC in Lacerta viridis show similarities with those of MOC in other lizards and in snakes. Kinematically, the pattern of jaw and tongue displacements of Lacerta viridis during chemosensory activities shows similarities with those that occur during drinking and prey capture.


2017 ◽  
Vol 90 (3) ◽  
pp. 224-231 ◽  
Author(s):  
Daisuke Kondoh ◽  
Kenichi Watanabe ◽  
Kaori Nishihara ◽  
Yurie S. Ono ◽  
Kentaro G. Nakamura ◽  
...  

The olfactory system of mammals comprises a main olfactory system that detects hundreds of odorants and a vomeronasal system that detects specific chemicals such as pheromones. The main (MOB) and accessory (AOB) olfactory bulbs are the respective primary centers of the main olfactory and vomeronasal systems. Most mammals including artiodactyls possess a large MOB and a comparatively small AOB, whereas most cetaceans lack olfactory bulbs. The common hippopotamus (Hippopotamus amphibius) is semiaquatic and belongs to the order Cetartiodactyla, family Hippopotamidae, which seems to be the closest extant family to cetaceans. The present study evaluates the significance of the olfactory system in the hippopotamus by histologically analyzing the MOB and AOB of a male common hippopotamus. The MOB comprised six layers (olfactory nerve, glomerular, external plexiform, mitral cell, internal plexiform, and granule cell), and the AOB comprised vomeronasal nerve, glomerular, plexiform, and granule cell layers. The MOB contained mitral cells and tufted cells, and the AOB possessed mitral/tufted cells. These histological features of the MOB and the AOB were similar to those in most artiodactyls. All glomeruli in the AOB were positive for anti-Gαi2, but weakly positive for anti-Gαo, suggesting that the hippopotamus vomeronasal system expresses vomeronasal type 1 receptors with a high affinity for volatile compounds. These findings suggest that the olfactory system of the hippopotamus is as well developed as that of other artiodactyl species and that the hippopotamus might depend on its olfactory system for terrestrial social communication.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1844 ◽  
Author(s):  
Stephan T. Leu ◽  
Grant Jackson ◽  
John F. Roddick ◽  
C. Michael Bull

Individual movement influences the spatial and social structuring of a population. Animals regularly use the same paths to move efficiently to familiar places, or to patrol and mark home ranges. We found that Australian sleepy lizards (Tiliqua rugosa), a monogamous species with stable pair-bonds, repeatedly used the same paths within their home ranges and investigated whether path re-use functions as a scent-marking behaviour, or whether it is influenced by site familiarity. Lizards can leave scent trails on the substrate when moving through the environment and have a well-developed vomeronasal system to detect and respond to those scents. Path re-use would allow sleepy lizards to concentrate scent marks along these well-used trails, advertising their presence. Hypotheses of mate attraction and mating competition predict that sleepy lizard males, which experience greater intra-sexual competition, mark more strongly. Consistent with those hypotheses, males re-used their paths more than females, and lizards that showed pairing behaviour with individuals of the opposite sex re-used paths more than unpaired lizards, particularly among females. Hinterland marking is most economic when home ranges are large and mobility is low, as is the case in the sleepy lizard. Consistent with this strategy, re-used paths were predominantly located in the inner 50% home range areas. Together, our detailed movement analyses suggest that path re-use is a scent marking behaviour in the sleepy lizard. We also investigated but found less support for alternative explanations of path re-use behaviour, such as site familiarity and spatial knowledge. Lizards established the same number of paths, and used them as often, whether they had occupied their home ranges for one or for more years. We discuss our findings in relation to maintenance of the monogamous mating system of this species, and the spatial and social structuring of the population.


2002 ◽  
Vol 205 (19) ◽  
pp. 3087-3092 ◽  
Author(s):  
Bruce A. Young ◽  
Amie Aguiar

SUMMARYIn order to test the hypothesis that snakes can not only perceive airborne sounds, but also respond to them, an acoustic isolation chamber was designed and constructed to perform best within the 150-450 Hz range in which snakes perceive sound. Suspended within this acoustic chamber was a steel mesh basket designed to minimize the potential for groundborne vibrations. A synthesized tone was created out of 20 different 150 ms sounds, each separated by a 50 ms period of silence; the acoustic energy of each of the 20 sounds was concentrated between 200-400 Hz, and each sound included frequency modulation. The trial stimuli were presented to western diamondback rattlesnakes Crotalus atrox at a level 5-10 dB above their perception threshold. Four significant behavioural responses were observed upon stimulus presentation: cessation of body movements, reduction or cessation of tongue flicking, rapid jerks of the head and rattling. At least one significant behavioural response was observed in 92% of the behavioural trials. This study provides the first experimental evidence that snakes can respond behaviourally to airborne sounds.


Sign in / Sign up

Export Citation Format

Share Document