Omnivorous lacertid lizards (Gallotia) from El Hierro, Canary Islands, can identify prey and plant food using only chemical cues

2001 ◽  
Vol 79 (5) ◽  
pp. 881-887 ◽  
Author(s):  
William E Cooper, Jr. ◽  
Valentín Pérez-Mellado
Keyword(s):  
Tomato Fruit ◽  
Tongue Flick ◽  
Plant Food ◽  
El Hierro ◽  
Plant Chemical ◽  
Lacertid Lizards ◽  
Chemical Discrimination ◽  
Chemical Stimuli ◽  
Tongue Flicking ◽  
The One

We studied lingual and biting responses to food chemicals by two species of omnivorous lacertid lizards, the Canary Island endemics Gallotia simonyi (the giant lizard of El Hierro) and Gallotia caesaris (Boettger's lizard), to ascertain their ability to discriminate between prey and plant food chemicals on the one hand and control stimuli on the other. We recorded frequencies of tongue-flicking and latency to bite in 60-s trials in which chemical stimuli on cotton-tipped applicators were presented to the lizards. Both species exhibited prey-chemical discrimination, as indicated by elevated tongue-flick rates and higher proportions of individuals biting in response to surface chemicals from crickets. Both species exhibited plant-chemical discrimination, as indicated by significantly greater tongue-flick rates and biting frequency in response to chemicals from tomato fruit than to the control stimuli. Juvenile G. simonyi responded much more strongly to chemical stimuli from tomato fruit than from leaves of Psoralea bituminosa, which is not a preferred food for juveniles. The findings are consistent with the hypothesis that chemosensory discrimination evolves in omnivorous lizards to permit evaluation of food quality, resulting in correspondence between plant diet and plant-chemical discrimination, both being absent in insectivores. The results are also consistent with the hypothesis that prey-chemical discrimination is retained and plant-chemical discrimination evolves in the omnivorous lizards derived from actively foraging insectivores.

Prey chemical discrimination by a diploglossine lizard, the giant Hispaniolan galliwasp (Celestus warreni)

2009 ◽  
Vol 30 (1) ◽  
pp. 135-140 ◽  
Author(s):  
William Cooper ◽  
Kelly Bradley
Keyword(s):  
Composite Index ◽  
Response Strength ◽  
Tongue Flick ◽  
Foraging Mode ◽  
Plant Chemical ◽  
Prey Chemicals ◽  
Chemical Discrimination ◽  
Active Forager ◽  
Tongue Flicking ◽  
And Control

AbstractPrey chemical discrimination, the ability to respond differentially to prey chemicals and control stimuli, enables many squamate reptiles to locate and identify prey using chemical cues sampled by tongue-flicking and analyzed by vomerolfaction. Among lizards this ability is limited to species that are active foragers having insectivorous/carnivorous diets and to omnivores and herbivores, even those derived from ancestral ambush foragers. We experimentally studied responses by hatchlings of giant Hispaniolan galliwasps, Celestus warreni, which appear to have a strict animal diet and are putatively active foragers, to prey chemicals and control substances. More individuals tongue-flicked in the cricket condition than the water condition. Response strength indicated by the tongue-flick attack score, a composite index of response strength based on number of tongue-flicks, biting (one lizard) and latency to bite, was greater in response to cricket stimuli than plant (lettuce) stimuli, cologne or distilled water. Thus, the galliwasps exhibited prey chemical discrimination. Celestus warreni, the first representative of Diploglossinae to be tested, exhibits chemosensory behavior similar to that of other anguids. Although no quantitative data on foraging mode are available, another diploglossine, Diploglossus vittatus, is an active forager. The limitation of prey chemical discrimination to active foragers among lizards with animal diets lend further support to the likelihood that C. warreni is an active forager. The galliwasps did not exhibit plant chemical discrimination.

Plant chemical discriminations by an herbivorous iguanid lizard, Sauromalus ater

2001 ◽  
Vol 22 (1) ◽  
pp. 69-80 ◽  
Author(s):  
William Cooper ◽  
Matthew Flowers
Keyword(s):  
Common Ancestor ◽  
Natural Populations ◽  
Romaine Lettuce ◽  
Data Set ◽  
Plant Chemical ◽  
Chemical Discrimination ◽  
The Common ◽  
Chemical Stimuli ◽  
Tongue Flicking ◽  
And Control

AbstractWe experimentally studied the ability of the iguanid lizard Sauromalus ater to discriminate between plant and animal foods and control stimuli using only chemical cues. When chemicals were presented on cotton swabs, the lizards exhibited stronger responses, as indicated by tongue-flicking and biting, to chemical stimuli from romaine lettuce than from crickets and control substances. Responses to plant and animal food did not differ significantly in S. ater, which eats animal prey only occasionally in natural populations. Although there were no significant differences between responses to cricket chemicals and other stimuli for the entire data set, those individuals that ate or attacked crickets tongue-flicked at high rates in response to cricket chemicals. Based on the presence of herbivory and plant chemical discrimination in three iguanid genera, it is likely that plant chemical discrimination is ubiquitous in iguanids. Given the uncertainty of iguanian phylogeny, the evolution of herbivory and response to plant chemicals cannot be traced with confidence. However, it appears very likely that lingually mediated plant chemical discriminations evolved in the common ancestor of Iguanidae or earlier in iguanian history in response to a shift to an herbivorous diet.

Food-chemical discrimination and correlated evolution between plant diet and plant-chemical discrimination in lacertiform lizards

2002 ◽  
Vol 80 (4) ◽  
pp. 655-663 ◽  
Author(s):  
William E Cooper Jr., ◽  
Janalee P Caldwell ◽  
Laurie J Vitt ◽  
Valentín Pérez-Mellado ◽  
Troy A Baird
Keyword(s):  
Chemical Cues ◽  
Experimental Studies ◽  
Correlated Evolution ◽  
Plant Foods ◽  
Plant Chemical ◽  
Chemical Discrimination ◽  
Herbivorous Species ◽  
Quality Of Food ◽  
Tongue Flicking

Lizards use chemical cues to locate and identify prey and plant food, assess the nutritional quality of food, and detect plant toxins. Among insectivorous lizards, all actively foraging species studied respond strongly to prey chemicals sampled lingually, but ambush foragers do not. Much recent research has been devoted to assessing differential responses to food and nonfood chemicals (i.e., food-chemical discrimination) by omnivorous and herbivorous species and determining whether correlated evolution has occurred between plant diet and plant-chemical discrimination. We conducted experimental studies of food-chemical discrimination by two species of teiid lizards, the omnivorous Cnemidophorus murinus and the actively foraging insectivorous Ameiva ameiva. The omnivore distinguished both prey and plant chemicals from control substances. The insectivore exhibited prey-chemical, but not plant-chemical, discrimination, as indicated by tongue-flicking and biting. A comparative analysis using concentrated-changes tests showed that correlated evolution has occurred between plant consumption and plant-chemical discrimination in a major lizard taxon, Lacertiformes. These results extend and strengthen previous findings of similar correlated evolution to a new group and add to a growing database indicating that omnivorous lizards use chemical cues to assess both prey and plant foods.

scholarly journals Do predators prefer toxic animals? A case of chemical discrimination by an asian snake that sequesters firefly toxins

2021 ◽  
Author(s):  
Masaya Fukuda ◽  
Rinako Ujiie ◽  
Takato Inoue ◽  
Qin Chen ◽  
Chengquan Cao ◽  
...  
Keyword(s):  
The Other ◽  
Chemical Cue ◽  
Behavioral Experiments ◽  
Proximate Mechanisms ◽  
The Third ◽  
Other Hand ◽  
Y Maze ◽  
Chemical Discrimination ◽  
Chemical Stimuli ◽  
Tongue Flicking

Abstract Several Asian natricine snakes of the genus Rhabdophis feed on toads and sequester steroidal cardiac toxins known as bufadienolides (BDs) from them. A recent study revealed that species of the R. nuchalis Group ingest lampyrine fireflies to sequester BDs. Although several species of fireflies are distributed in the habitat of the R. nuchalis Group, only lampyrine fireflies, which have BDs, included in the diet of these snakes. Thus, we hypothesized that the R. nuchalis Group chemically distinguishes fireflies that have BDs from those that do not have BDs. We also predicted that the R. nuchalis Group detects BDs as the chemical cue of toxin source. To test these predictions, we conducted three behavioral experiments using R. chiwen, which belongs to the R. nuchalis Group. In the first experiment, R. chiwen showed a moderate tongue flicking response to cinobufagin, a compound of BDs. On the other hand, the snake showed a higher response to the chemical stimuli of lampyrine fireflies (BD fireflies) than those of lucioline fireflies (non-BD fireflies). In the second experiment, in which we provided live BD and non-BD fireflies, the snake voluntarily consumed only the former. In the third, a Y-maze experiment, the snake tended to select the chemical trail of BD fireflies more frequently than that of non-BD fireflies. These results demonstrated that R. chiwen discriminates BD fireflies from non-BD fireflies, but the prediction that BDs are involved in this discrimination was not fully supported. To identify the proximate mechanisms of the recognition of novel toxic prey in the R. nuchalis Group, further investigation is necessary.

Strong response to anuran chemical cues by an extreme dietary specialist, the eastern hog-nosed snake (Heterodon platirhinos)

2007 ◽  
Vol 85 (5) ◽  
pp. 619-625 ◽  
Author(s):  
William E. Cooper, ◽  
Stephen Secor
Keyword(s):  
Chemical Cues ◽  
Response Strength ◽  
Tongue Flick ◽  
Vomeronasal System ◽  
Potential Prey ◽  
Food Cues ◽  
Strong Response ◽  
Bufo Terrestris ◽  
Plant Chemical ◽  
Tongue Flicking

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.

Responses to prey and plant chemicals by three iguanian lizards: relationship to plants in the diet

2001 ◽  
Vol 22 (3) ◽  
pp. 349-361 ◽  
Author(s):  
Robert Espinoza ◽  
Jason Habegger ◽  
William Cooper
Keyword(s):  
Ceramic Tiles ◽  
Plant Chemical ◽  
Plant Chemicals ◽  
Prey Chemicals ◽  
Chemical Discrimination ◽  
Chemical Stimuli ◽  
And Control

AbstractWe examined responses of three iguanian lizards, the phrynosomatid Sceloporus poinsettii and the tropidurids Tropidurus hispidus and Phymaturus punae, to prey chemicals and plant chemicals. When chemical stimuli were presented on cotton swabs or on ceramic tiles, neither S. poinsettii nor T. hispidus discriminated among prey, plant, and control stimuli. In contrast, an individual of P. punae discriminated both prey and plant chemicals from control stimuli in swab tests, typically biting swabs bearing prey or plant cues. These findings are consistent with the hypothesis that plant chemical discrimination evolves in herbivorous iguanians such as P. punae. Sceloporus poinsettii, which appears to be entirely insectivorous at some times, but eats substantial quantities of flowers at others, did not discriminate among the stimuli. Because all previously tested herbivores and omnivores responded strongly to prey and plant chemicals, the absence of such discriminations by S. poinsettii raises questions about the degree and regularity of herbivory that may be required for plant chemical discrimination to evolve. The results extend the absence of prey chemical discrimination in ambush foragers to T. hispidus.

Foraging modes in lacertid lizards from southern Africa

1999 ◽  
Vol 20 (3) ◽  
pp. 299-311 ◽  
Author(s):  
William E. Cooper ◽  
Martin J. Whiting
Keyword(s):  
Southern Africa ◽  
Published Data ◽  
Foraging Mode ◽  
Lacertid Lizards ◽  
Foraging Modes ◽  
History Of ◽  
Tongue Flicking ◽  
Ambush Foraging

AbstractMost lacertids are active foragers, but intrafamilial variation in foraging mode is greater than in most lizard families. We collected data on eight species of African lacertids to assess this variation. Both active and ambush foraging occurred within Pedioplanis and Meroles. Meroles ctenodactylus had a proportion of time moving and proportion of attacked prey detected while moving intermediate to those for actively foraging and ambushing Pedioplanis, but its number of movements per minute was exceptionally high. This species has a unique mixed foraging mode. Like active foragers, it seeks food by tongue-flicking while moving and spends a high percentage of the time moving. Like ambush foragers, it searches visually for prey during pauses between movements. Our findings confirm published data on four Kalahari lacertids. We discuss the history of foraging modes in advanced lacertids.

On the Occurrence and Structure of Subunits of Endopolygalacturonase Isoforms in Mature-Green and Ripening Tomato Fruits

1991 ◽  
Vol 18 (1) ◽  
pp. 65 ◽  
Author(s):  
BJ Pogson ◽  
CJ Brady ◽  
GR Orr
Keyword(s):  
Tomato Fruit ◽  
Exchange Chromatography ◽  
Molecular Forms ◽  
Cation Exchange Chromatography ◽  
Ripe Fruit ◽  
Tomato Fruits ◽  
Green Fruit ◽  
C Terminus ◽  
The One ◽  
Polygalacturonase Activity

Endopolygalacturonase [poly(1,4-α-galacturonide) glycanohydrolase EC 3.2.1.151 occurs in tomato fruit in three molecular forms- PG1, PG2A, PG2B. Trace amounts of PG1, 1-10 pkat g-1 are shown to occur in mature-green fruit as compared to 17 nkat in ripe fruit. As polygalacturonase activity increases through ripening, the percentage of the activity due to PG1 decreases progressively from 100 to less than 20. On fully or partly demethylated substrates, PG1 is more active than PG2 when the ionic strength is that expected in the tissue apoplast. A method for purifying PGI from ripe fruit is described. PG1 preparations contain polypeptides of Mr 45, 43 and 38 thousand. The Mr 43 thousand and 45 thousand components correspond in size to PG2A and PG2B and are detected by antisera raised against PG2A. The M, 38 thousand polypeptide is immunologically distinct. From carbohydrate and amino acid analyses, this polypeptide appears to contain 2870 carbohydrate as glucosamine, mannose, xylose and fucose attached to a polypeptide of estimated Mr 28 342 that is rich in tyrosine and glycine. A method for purifying the subunits of PG1 by cation exchange chromatography in 6 M urea is described. PG2A and PG2B were separated by column chromatography and shown to have identical N-terminal sequences, and serine at the C-terminus. PG2A and PG2B are confirmed as two glycoforms of the one polypeptide. The possibility that PGl consists of populations of molecules containing either PG2A or PG2B coupled with the Mr 38 thousand polypeptide is discussed.

Snake tongue-flicking: transfer mechanics to Jacobson's organ

1981 ◽  
Vol 59 (9) ◽  
pp. 1651-1657 ◽  
Author(s):  
James C. Gillingham ◽  
David L. Clark
Keyword(s):  
Vomeronasal Organ ◽  
Electron Microscopic Examination ◽  
Ventral Surface ◽  
Tongue Flick ◽  
Garter Snakes ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic ◽  
Food Odors ◽  
Tongue Flicking ◽  
Jacobson's Organ

Cinematographic analysis of the open-mouthed tongue flick of rat snakes (Elaphe) revealed elevation of the anterior processes following tongue retraction into the lingual sheath. The ventral surface of the tongue makes contact with these processes on each retraction and these processes are directly aligned with Jacobson's (vomeronasal) organ in the roof of the mouth. Scanning electron microscopic examination of the anterior process surface reveals an increased surface area through oblique ridges. Experimental removal of these structures prevents open-field detection of food odors in garter snakes (Thamnophis). These data indicate that this structure is the vehicle for transfer of substances to Jacobson's organ during snake chemosensation.

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