scholarly journals Avoiding being stung or bitten – prey capture behaviors of the ant-eating Texas horned lizard (Phrynosoma cornutum)

Biology Open ◽  
2021 ◽  
Vol 10 (3) ◽  
Author(s):  
Ismene Fertschai ◽  
Wade C. Sherbrooke ◽  
Matthias Ott ◽  
Boris P. Chagnaud
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Harvester Ants ◽  
Phrynosoma Cornutum ◽  
Video Recordings ◽  
Directional Movement ◽  
Plasma Factor ◽  
Ant Venom ◽  
Horned Lizards ◽  
Ant Eating

ABSTRACT Horned lizards (Phrynosoma) are specialized predators, including many species that primarily feed on seed harvester ants (Pogonomyrmex). Harvester ants have strong mandibles to husk seeds or defensively bite, and a venomous sting. Texas horned lizards possess a blood plasma factor that neutralizes harvester ant venom and produce copious mucus in the pharynx and esophagus, thus embedding and incapacitating swallowed ants. We used high-speed video recordings to investigate complexities of their lingual prey capture and handling behavior. Lizards primarily strike ants at their mesosoma (thorax plus propodeum of abdomen). They avoid the head and gaster, even if closer to the lizard, and if prey directional movement is reversed. Orientation of captured ants during retraction is with head first (rostral), thus providing initial mucus coating of the mandibles. Prey capture accuracy and precise handling illustrates the specificity of adaptations of horned lizards in avoiding harm, and the challenges lizards face when feeding on dangerous prey.

The Mechanism of Tongue Projection in Chameleons: I. Electromyographic Tests of Functional Hypotheses

1992 ◽  
Vol 168 (1) ◽  
pp. 1-21 ◽  
Author(s):  
PETER C. WAINWRIGHT ◽  
ALBERT F. BENNETT
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Activity Patterns ◽  
Motor Pattern ◽  
Companion Paper ◽  
Posterior Portion ◽  
Video Recordings ◽  
Single Burst ◽  
Intense Activity ◽  
Test Current

In this paper we document the activity of key muscles of the tongue, hyobranchial apparatus and head during prey capture in the lizard Chamaeleo jacksonii Boulenger and use these data to test current hypotheses of chameleon tongue function. Electromyographic recordings were made during 27 feedings from nine individuals and synchronized with high-speed video recordings (200 fields s−1), permitting an assessment of the activity of muscles relative to the onset of tongue projection, contact between tongue and prey, and tongue retraction. Four major results were obtained. (1) The hyoglossi muscles exhibit a single burst of activity that begins between 10 ms before and 20 ms after the onset of tongue projection and continues throughout the period of tongue retraction. (2) The accelerator muscle exhibits a biphasic activity pattern, with the first burst lasting about 185 ms and ending an average of 10.6 ms prior to the onset of projection. (3) The accelerator muscle shows regional variation in morphology that corresponds with variation in motor pattern. The anterior region of the muscle, unlike the posterior portion, exhibits only a single burst of activity that begins 2.5 ms after the onset of tongue projection and is thus not involved in launching the tongue. (4) The geniohyoidei, sternohyoidei, sternothyroidei, depressor mandibulae, adductor mandibulae and pterygoideus all exhibit activity patterns consistent with previously reported kinematic patterns and their proposed roles. The major implications of these results for models of the chameleon feeding mechanism are (1) that the hyoglossi do not act to hold the tongue on the entoglossal process during a loading period prior to tongue projection, and (2) that the presence of 185 ms of intense activity in the accelerator muscle prior to tongue projection suggests the presence of a preloading mechanism, the nature of which is the subject of the companion paper.

Use of sonomicrometry demonstrates the link between prey capture kinematics and suction pressure in largemouth bass

2002 ◽  
Vol 205 (22) ◽  
pp. 3445-3457 ◽  
Author(s):  
Christopher P. J. Sanford ◽  
Peter C. Wainwright
Keyword(s):  
Largemouth Bass ◽  
High Speed ◽  
Prey Capture ◽  
Buccal Cavity ◽  
Micropterus Salmoides ◽  
Sampling Rate ◽  
Great Promise ◽  
Suction Pressure ◽  
Video Recordings ◽  
Explosive Expansion

SUMMARYSuction feeding in fishes is the result of a highly coordinated explosive expansion of the buccal cavity that results in a rapid drop in pressure. Prey are drawn into the mouth by a flow of water that is generated by this expansion. At a gross level it is clear that the expansion of the buccal cavity is responsible for the drop in pressure. However, attempts using high-speed video recordings to demonstrate a tight link between prey capture kinematics and suction pressure have met with limited success. In a study with largemouth bass Micropterus salmoides, we adopted a new technique for studying kinematics, sonomicrometry, to transduce the movement of skeletal elements of the head during feeding, and synchronized pressure recordings at a sampling rate of 500 Hz. From the positional relationships of six piezoelectric crystals we monitored the internal movements of the buccal cavity and mouth in both mid-sagittal and transverse planes. We found that peak subambient pressure was reached very early in the kinematic expansion of the buccal cavity, occurring at the time when the rate of percentage change in buccal volume was at its peak. Using multiple regression analyses we were consistently able to account for over 90%, and in the best model 99%, of the variation in buccal pressure among strikes using kinematic variables. Sonomicrometry shows great promise as a method for documenting movements of biological structures that are not clearly visible in the external view provided by film and video recordings.

The mechanics of prey prehension in chameleons

2000 ◽  
Vol 203 (21) ◽  
pp. 3255-3263 ◽  
Author(s):  
A. Herrel ◽  
J.J. Meyers ◽  
P. Aerts ◽  
K.C. Nishikawa
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Prey Size ◽  
Nerve Transection ◽  
Surface Phenomena ◽  
High Speed Video ◽  
Video Recordings ◽  
Tongue Muscles ◽  
Stimulation Experiments ◽  
Prey Items

Iguanian lizards generally use their tongue to capture prey. Because lingual prehension is based on surface phenomena (wet adhesion, interlocking), the maximal prey size that can be captured is small. However, published records show that prey items eaten by chameleons include small vertebrates such as lizards and birds, indicating that these lizards are using a different prey prehension mechanism. Using high-speed video recordings, cineradiography, electromyography, nerve transection and stimulation experiments, we investigated the function of the tongue during prey capture. The results of these experiments indicate that chameleons have modified the primitive iguanian system by including a suction component in their prehension mechanism. Suction is generated by the activity of two modified intrinsic tongue muscles that pull the tongue pad inwards. Moreover, we demonstrate that the mechanism described here is a prerequisite for successful feeding.

scholarly journals Kinematics of feeding in the lizard Agama stellio

1996 ◽  
Vol 199 (8) ◽  
pp. 1727-1742 ◽  
Author(s):  
A Herrel ◽  
J Cleuren ◽  
F Vree
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Prey Type ◽  
The Body ◽  
Kinematic Data ◽  
Video Recordings ◽  
Lower Jaw ◽  
Feeding Cycle ◽  
Hyolingual Apparatus ◽  
Opening Phase

The kinematics of prey capture, intraoral transport and swallowing in lizards of the species Agama stellio (Agamidae) were investigated using cineradiography (50 frames s-1) and high-speed video recordings (500 frames s-1). Small metal markers were inserted into different parts of the upper and lower jaw and the tongue. Video and cineradiographic images were digitized, and displacements of the body, head, upper and lower jaw and the tongue were quantified. Twenty additional variables depicting displacements and timing of events were calculated. A factor analysis performed on the kinematic data separates prey capture and swallowing cycles from intraoral transport bites. However, the intraoral transport stage cannot be separated into chewing (reduction) and transport bites. The effect of prey type and size on the feeding kinematics of intraoral transport and swallowing cycles was investigated. During the intraoral transport stage, distinct aspects (e.g. durations, maximal excursions) of the gape and tongue cycle are modulated in response to both the size and type of the prey item. The results for A. stellio generally agree with a previous model, although it is the entire slow opening phase rather than solely the duration of the second part of this phase that is affected by the size of the prey. The intraoral transport cycles in A. stellio show the two synapomorphic characteristics of tetrapods (tongue-based terrestrial intraoral prey transport and the existence of a long preparatory period of prey compression). However, not all five characters of the feeding cycle previously proposed for amniotes are present in A. stellio. One major difference is that in A. stellio the recovery of the hyolingual apparatus does not take place during the slow opening phase but during the slow closing/powerstroke phase.

scholarly journals Prey Capturing Dynamics and Nanomechanically Graded Cutting Apparatus of Dragonfly Nymph

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 559
Author(s):  
Lakshminath Kundanati ◽  
Prashant Das ◽  
Nicola M. Pugno
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
High Speed ◽  
Prey Capture ◽  
High Speed Photography ◽  
Sensory Organs ◽  
Dragonfly Nymph ◽  
Drag Forces ◽  
Predatory Insects ◽  
Dragonfly Nymphs

Aquatic predatory insects, like the nymphs of a dragonfly, use rapid movements to catch their prey and it presents challenges in terms of movements due to drag forces. Dragonfly nymphs are known to be voracious predators with structures and movements that are yet to be fully understood. Thus, we examine two main mouthparts of the dragonfly nymph (Libellulidae: Insecta: Odonata) that are used in prey capturing and cutting the prey. To observe and analyze the preying mechanism under water, we used high-speed photography and, electron microscopy. The morphological details suggest that the prey-capturing labium is a complex grasping mechanism with additional sensory organs that serve some functionality. The time taken for the protraction and retraction of labium during prey capture was estimated to be 187 ± 54 ms, suggesting that these nymphs have a rapid prey mechanism. The Young’s modulus and hardness of the mandibles were estimated to be 9.1 ± 1.9 GPa and 0.85 ± 0.13 GPa, respectively. Such mechanical properties of the mandibles make them hard tools that can cut into the exoskeleton of the prey and also resistant to wear. Thus, studying such mechanisms with their sensory capabilities provides a unique opportunity to design and develop bioinspired underwater deployable mechanisms.

Kinematics of Tongue Projection in Chamaeleo Oustaleti

1991 ◽  
Vol 159 (1) ◽  
pp. 109-133 ◽  
Author(s):  
PETER C. WAINWRIGHT ◽  
DAVID M. KRAKLAU ◽  
ALBERT F. BENNETT
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Maximum Velocity ◽  
Head Movements ◽  
Florida State University ◽  
State University ◽  
Maximum Acceleration ◽  
Related Family ◽  
High Speed Cinematography ◽  
Tongue Movements

The kinematics of prey capture by the chamaeleonid lizard Chamaeleo oustaleti were studied using high-speed cinematography. Three feeding sequences from each of two individuals were analyzed for strike distances of 20 and 35 cm, at 30°C. Ten distances and angles were measured from sequential frames beginning approximately 0.5 s prior to tongue projection and continuing for about 1.0 s. Sixteen additional variables, documenting maximum excursions and the timing of events, were calculated from the kinematic profiles. Quantified descriptions of head, hyoid and tongue movements are presented. Previously unrecognized rapid protraction of the hyobranchial skeleton simultaneously with the onset of tongue projection was documented and it is proposed that this assists the accelerator muscle in powering tongue projection. Acceleration of the tongue occurred in about 20ms, reaching a maximum acceleration of 486 m s−2 and maximum velocity of 5.8m s−1 in 35 cm strikes. Deceleration of the tongue usually began within 5 ms before prey contract and the direction of tongue movement was reversed within 10 ms of prey contact. Retraction of the tongue, caused by shortening of the retractor muscles, reached a maximum velocity of 2.99 ms−1 and was complete 330 ms after prey contact. Projection distance influences many aspects of prey capture kinematics, particularly projection time, tongue retraction time and the extent of gape and head movements during tongue retraction, all of which are smaller in shorter feedings. Though several features of the chameleon strike have apparently been retained from lizards not capable of ballistic tongue projection, key differences are documented. Unlike members of a related family, the Agamidae, C. oustaleti uses no body lunge during prey capture, exhibits gape reduction during tongue projection and strongly depresses the head and jaws during tongue retraction. Note: Present address: Department of Biological Sciences, Florida State University, Tallahassee, FL 32306, USA.

Kinematic analysis of tongue movements during chemosensory behaviour in the European green lizard, Lacerta viridis (Reptilia: Lacertidae)

1992 ◽  
Vol 70 (10) ◽  
pp. 1886-1896 ◽  
Author(s):  
Véronique Goosse ◽  
Vincent L. Bels
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Principal Component ◽  
Upward Movement ◽  
High Speed Cinematography ◽  
Tongue Movements ◽  
Lacerta Viridis ◽  
Tongue Flicking ◽  
Stationary Interval ◽  
Tongue Displacement

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.

scholarly journals Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli , an ancient apex predator

2006 ◽  
Vol 3 (1) ◽  
pp. 77-80 ◽  
Author(s):  
Philip S.L Anderson ◽  
Mark W Westneat
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Mouth Opening ◽  
Biomechanical Model ◽  
Bite Force ◽  
Rapid Expansion ◽  
Large Individual ◽  
Linkage Mechanism ◽  
Feeding Mechanics ◽  
Four Bar Linkage

Placoderms are a diverse group of armoured fishes that dominated the aquatic ecosystems of the Devonian Period, 415–360 million years ago. The bladed jaws of predators such as Dunkleosteus suggest that these animals were the first vertebrates to use rapid mouth opening and a powerful bite to capture and fragment evasive prey items prior to ingestion. Here, we develop a biomechanical model of force and motion during feeding in Dunkleosteus terrelli that reveals a highly kinetic skull driven by a unique four-bar linkage mechanism. The linkage system has a high-speed transmission for jaw opening, producing a rapid expansion phase similar to modern fishes that use suction during prey capture. Jaw closing muscles power an extraordinarily strong bite, with an estimated maximal bite force of over 4400 N at the jaw tip and more than 5300 N at the rear dental plates, for a large individual (6 m in total length). This bite force capability is the greatest of all living or fossil fishes and is among the most powerful bites in animals.

The kinematics and mechanism of prey capture in the African pig-nosed frog (Hemisus marmoratum): description of a radically divergent anuran tongue.

1995 ◽  
Vol 198 (9) ◽  
pp. 2025-2040 ◽  
Author(s):  
D Ritter ◽  
K Nishikawa
Keyword(s):  
Feeding Behavior ◽  
Strong Evidence ◽  
Muscle Function ◽  
High Speed ◽  
Prey Capture ◽  
Three Dimensions ◽  
Muscle Denervation ◽  
Genioglossus Muscle ◽  
Pulling Forces ◽  
Hydraulic Mechanism

High-speed videography and muscle denervation experiments were used to quantify the feeding kinematics of Hemisus marmoratum and to test hypotheses of muscle function. The feeding behavior of H. marmoratum, which feeds on ants and termites, differs radically from that of other frogs that have been studied. During feeding in H. marmoratum, the tongue 'telescopes' straight out of the mouth, as opposed to the 'flipping' tongue trajectory observed in most other frogs. At the time of prey contact, two lateral lobes of tissue at the tongue tip envelop the prey. These lateral lobes are capable of applying significant pulling forces to the prey and the tongue is, therefore, described as prehensile. The trajectory of the tongue can be adjusted throughout protraction so that the frog can 'aim' its tongue in all three dimensions; distance, azimuth and elevation. Bilateral denervation of the genioglossus muscles results in a complete lack of tongue protraction, indicating that the genioglossus muscle is the main tongue protractor in H. marmoratum, as in other frogs. Thus, H. marmoratum provides strong evidence of functional conservatism of the genioglossus muscle within anurans. Bilateral denervation of the hyoglossus muscle indicates that although the hyoglossus is involved in several aspects of normal tongue retraction, including the prehensile capability of the tongue tip, it is not necessary for tongue retraction. Unilateral denervation of the genioglossus muscle causes significant deviation of the tongue towards the denervated side, providing evidence for a mechanism of lateral tongue aiming. On the basis of the kinematics of prey capture, the anatomy of the tongue and the results of the denervation experiments, we propose that H. marmoratum uses a hydraulic mechanism to protract its tongue.

Unilateral ciliary reversal and motor responses during prey capture by the ctenophore Pleurobrachia

1985 ◽  
Vol 114 (1) ◽  
pp. 443-461 ◽  
Author(s):  
S. L. Tamm ◽  
A. G. Moss
Keyword(s):  
High Frequency ◽  
Feeding Behaviour ◽  
High Speed ◽  
Prey Capture ◽  
Reverse Direction ◽  
Motor Responses ◽  
Ciliary Reversal ◽  
High Speed Cinematography

High-speed cinematography of feeding Pleurobrachia revealed a stereo-typed sequence of ciliary motor responses underlying the feeding behaviour of this ctenophore. Prey capture by a tentacle first elicited high frequency beating in all comb rows, propelling the animal forward at a rapid speed for several seconds. This was followed by a brief period of inactivity on some or all comb rows. Then comb rows adjacent to the catching tentacle beat in the reverse direction, causing the ctenophore to spin rapidly toward this side and sweeping the prey-catching tentacle to the opened mouth, which bent towards it. After engulfing the prey, the animal slowly swam forward to re-set the relaxed tentacles as a fishing net. The patterns, timing, onset and coordination of these ciliary responses, particularly the unilateral reversal of comb rows on the catching side, are analysed with respect to possible conducting pathways mediating this behaviour.

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