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.

Chemosensory discrimination of plant and animal foods by the omnivorous iguanian lizard Pogona vitticeps

2000 ◽  
Vol 78 (8) ◽  
pp. 1375-1379 ◽  
Author(s):  
William E Cooper, Jr.
Keyword(s):  
Visual Cues ◽  
Chemical Cues ◽  
Bearded Dragon ◽  
Chemical Discrimination ◽  
Pogona Vitticeps ◽  
Preferred Foods ◽  
Alfalfa Sprouts ◽  
Tongue Flicking ◽  
Tongue Flicks

Most iguanian lizards are insectivores that do not use chemical cues sampled by tongue-flicking to identify prey before attacking, but the sole iguanian herbivore previously studied did so. To investigate the effects of a partially herbivorous diet on responses to food chemicals, I conducted an experiment to determine whether the omnivorous bearded dragon (Pogona vitticeps) has a similar ability. Chemical stimuli from crickets and carrots, both preferred foods, and alfalfa sprouts, and deionized water (a nonpreferred food and odorless control, respectively) were presented on cotton-tipped applicators. The lizards responded more strongly to both preferred foods than to the controls, performing more tongue flicks and biting the cotton in a greater number of trials. It is hypothesized that lingually mediated food-chemical discrimination is useful to herbivorous and omnivorous lizards for identifying plant and animal foods and for evaluating the quality of plant foods. The insectivorous ambush foragers ancestral to P. vitticeps could not locate prey by tongue-flicking repeatedly at an ambush post and do not exhibit prey-chemical discrimination. Adding plants to the diet altered the selective milieu because plants approached using visual cues can be evaluated using chemical cues, allowing the evolution of the ability to discriminate between plant-food chemicals. The ability to identify animal prey by tongue-flicking may have evolved through correlated evolution with chemosensory identification of plants or specifically for locating or identifying immobile prey.

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.

scholarly journals Mathematical and Analytical Evaluation of Paste Products Quality

2021 ◽  
Vol 4 (2) ◽  
pp. 332-344
Author(s):  
Victor Guts ◽  
Olga Koval ◽  
Svitlana Bondar
Keyword(s):  
Mathematical Model ◽  
Differential Equations ◽  
Analytical Approach ◽  
Experimental Studies ◽  
Control Sample ◽  
Poultry Meat ◽  
Analytical Evaluation ◽  
Organoleptic Evaluation ◽  
Quality Of Food

Topicality. In modern conditions, the society feels a growing demand in products made from natural ingredients of high nutritional value. Such products include meat pastes, the quality of which depends on their recipe, technological processes, equipment, and modes of its operation. With the implementation of innovative technological regimes and new equipment, there is a necessity to determine and prognosticate the quality of food products at all stages of their production and sale. According to the mentioned above, as well as economic feasibility of using automated systems for technological processes management, there is a need to elaborate a new mathematical and analytical approach to assessing and prognosticating changes in the quality of meat paste with various additives. Aim and research methods. The aim of this research is to elaborate a method for modeling the material system state, based on differential equations of kinetics of biochemical processes, assessment, and prognostication of food quality. Research methods. The method of mathematical and analytical evaluation of the paste products quality is grounded on modified mathematical models, differential equations, visualisation of research results in the form of 3D graphs, obtained by using symbolic computer mathematics. The quality of new meat paste products is compared with the quality of the paste, which is assumed to be relatively optimal according to the main organoleptic parameters of sensory quality assessment and control sample. The control sample of the paste is cooked according to the classical technology, and the recipe (GSTU 4424:2005). The prototype samples are cooked according to the innovative technology, which involves adding mechanically deboned poultry meat to the main raw material. Results. New results of analytical and experimental studies of the quality of meat paste products, cooked according to the classic recipe with the use of mechanically deboned poultry meat, are offered. The method for determining the coefficients, included in the mathematical model for assessing the meat paste products quality, their analytical relation with the optimization parameter, is elaborated. The expediency of using modern methods of symbolic computer mathematics for solving and analysing differential equations, presenting results in 3D graphs, is proved. The conducted research makes it possible to prognosticate the quality of food products, to control possible changes in their recipe while using various additives, to carry out elaborating new paste products. Conclusions and discussion. Based on the results of theoretical and experimental studies, a new mathematical model for estimating the quality of meat paste products in the form of the first-order differential equation, is offered. Its analogue is the equations, recommended for modeling the processes of biochemical kinetics. It is proved that the computer programme of mathematical and analytical research and prognostication the foodstuff quality (Goots et al., 2018) is universal. The offered mathematical model makes it possible to envision the quality of meat paste products, based on organoleptic evaluation. With its help, it becomes possible to determine the vector of possible changes in product quality and its optimisation, while elaborating the 3D graph. Mathematical and analytical assessment of the new paste products quality highlights that the partial replacement of the main meat raw by mechanically deboned poultry meat, and in pastes, made according to classical technology and the GSTU recipe (4424:2005), does not really reduce the parameters of organoleptic evaluation. In some cases, they are even higher than in the control paste samples, and very close to optimal ones. This new mathematical and analytical approach to assessing the paste products quality is promising in new culinary products elaboration in the restaurant business.

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.

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.

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