Escape behavior of Side-blotched Lizards (Uta stansburiana) in response to model predators

2017 ◽  
Vol 95 (12) ◽  
pp. 965-973 ◽  
Author(s):  
E.A. Wagner ◽  
P.A. Zani

Few field studies have tested for geographic variation in escape behavior and even fewer have examined responses of prey to multiple predators despite most prey occurring in multipredator environments. We performed 458 escape trials on Side-blotched Lizards (Uta stansburiana Baird and Girard, 1852) from 10 populations that differed in predator abundances. We quantified escape behavior of Side-blotched Lizards when approached with one of two model predators: a lizard (Great Basin Collared Lizard (Crotaphytus bicinctores N.M. Smith and Tanner, 1972)) or a snake (Western Yellow-bellied Racer (Coluber mormon Baird and Girard, 1852)). Our results suggest that the escape responses of Side-blotched Lizards (flight initiation distance, distance fled, refuge entry) do not differ when approached by either a model predatory lizard or a model predatory snake. Nor do the escape responses of individual Side-blotched Lizards differ in relation to the abundances of predatory lizards or snakes in the local environment. Rather, only the directness of fleeing toward a refuge differed based on model predator type with Side-blotched Lizards fleeing more directly toward a refuge in response to a model lizard. These findings suggest that Side-blotched Lizards tend to use a more generalized escape response to approaching predators.

1989 ◽  
Vol 146 (1) ◽  
pp. 287-306 ◽  
Author(s):  
R. Hoy ◽  
T. Nolen ◽  
P. Brodfuehrer

The acoustic startle/escape response is a phylogenetically widespread behavioral act, provoked by an intense, unexpected sound. At least six orders of insects have evolved tympanate ears that serve acoustic behavior that ranges from sexual communication to predator detection. Insects that fly at night are vulnerable to predation by insectivorous bats that detect and locate their prey by using biosonar signals. Of the six orders of insects that possess tympanate hearing organs, four contain species that fly at night and, in these, hearing is sensitive to a range of ultrasonic frequencies found in the biosonar signals of bats. Laboratory and field studies have shown that these insects (including some orthopterans, lepidopterans, neuropterans and dictyopterans), when engaged in flight behavior, respond to ultrasound by suddenly altering their flight, showing acoustic startle or negative phonotaxis, which serve as bat-avoidance behavior. A neural analysis of ultrasound-mediated escape behavior was undertaken in the field cricket Telegryllus oceanicus. An identified thoracic interneuron, int-1, was shown to trigger the escape response, but only when the cell was driven (synaptically or electrically) at high spike rates, and only when the insect was performing flight behavior; avoidance steering only occurs in the appropriate behavioral context: flight. Thus, significant constraints operate upon the ability of int-1 to trigger the escape response. The integration of auditory input and flight central pattern generator output occurs in the brain. It is found that neural activity descending from the brain in response to stimulation by ultrasound is increased when the insect is flying compared to when it is not. Although the behavioral act of avoidance steering may appear to be a simple reflex act, further analysis shows it to be anything but simple.


2018 ◽  
Author(s):  
Bryan C. Daniels ◽  
William S. Ryu ◽  
Ilya Nemenman

AbstractThe roundworm C. elegans exhibits robust escape behavior in response to rapidly rising temperature. The behavior lasts for a few seconds, shows history dependence, involves both sensory and motor systems, and is too complicated to model mechanistically using currently available knowledge. Instead we model the process phenomenologically, and we use the Sir Isaac dynamical inference platform to infer the model in a fully automated fashion directly from experimental data. The inferred model requires incorporation of an unobserved dynamical variable, and is biologically interpretable. The model makes accurate predictions about the dynamics of the worm behavior, and it can be used to characterize the functional logic of the dynamical system underlying the escape response. This work illustrates the power of modern artificial intelligence to aid in discovery of accurate and interpretable models of complex natural systems.


2021 ◽  
Author(s):  
Nodoka Sato ◽  
Hisashi Shidara ◽  
Hiroto Ogawa

ABSTRACTAnimals detect approaching predators via sensory inputs through various modalities and immediately show an appropriate behavioral response to survive. Escape behavior is essential to avoid the predator’s attack and is more frequently observed than other defensive behaviors. In some species, multiple escape responses are exhibited with different movements. It has been reported that the approaching speed of a predator is important in choosing which escape action to take among the multiple responses. However, it is unknown whether other aspects of sensory stimuli, that indicate the predator’s approach, affect the selection of escape responses. We focused on two distinct escape responses (running and jumping) to a stimulus (short airflow) in crickets and examined the effects of multiple stimulus aspects (including the angle, velocity, and duration) on the choice between these escape responses. We found that the faster and longer the airflow, the more frequently the crickets jumped, meaning that they could choose their escape response depending on both velocity and duration of the stimulus. This result suggests that the neural basis for choosing escape responses includes the integration process of multiple stimulus parameters. It was also found that the moving speed and distance changed depending on the stimulus velocity and duration during running but not during jumping, suggesting higher adaptability of the running escape. In contrast, the movement direction was accurately controlled regardless of the stimulus parameters in both responses. The escape direction depended only on stimulus orientation, but not on velocity and duration.Summary statementWhen air currents triggering escape are faster and longer, crickets more frequently jump than run. Running speed and distance depend on stimulus velocity and duration, but direction control is independent.


2020 ◽  
Author(s):  
Bibi Nusreen Imambocus ◽  
Annika Wittich ◽  
Federico Tenedini ◽  
Fangmin Zhou ◽  
Chun Hu ◽  
...  

AbstractAnimals display a plethora of escape behaviors when faced with environmental threats. Selection of the appropriate response by the underlying neuronal network is key to maximize chances of survival. We uncovered a somatosensory network in Drosophila larvae that encodes two escape behaviors through input-specific neuropeptide action. Sensory neurons required for avoidance of noxious light and escape in response to harsh touch, each converge on discrete domains of the same neuromodulatory hub neurons. These gate harsh touch responses via short Neuropeptide F, but noxious light avoidance via compartmentalized, acute Insulin-like peptide 7 action and cognate Relaxin-family receptor signaling in connected downstream neurons. Peptidergic hub neurons can thus act as central circuit elements for first order processing of converging sensory inputs to gate specific escape responses.One Sentence SummaryCompartment-specific neuropeptide action regulates sensory information processing to elicit discrete escape behavior in Drosophila larvae.


1998 ◽  
Vol 201 (22) ◽  
pp. 3041-3055 ◽  
Author(s):  
MW Westneat ◽  
ME Hale ◽  
MJ Mchenry ◽  
JH Long

The fast-start escape response is a rapid, powerful body motion used to generate high accelerations of the body in virtually all fishes. Although the neurobiology and behavior of the fast-start are often studied, the patterns of muscle activity and muscle force production during escape are less well understood. We studied the fast-starts of two basal actinopterygian fishes (Amia calva and Polypterus palmas) to investigate the functional morphology of the fast-start and the role of intramuscular pressure (IMP) in escape behavior. Our goals were to determine whether IMP increases during fast starts, to look for associations between muscle activity and elevated IMP, and to determine the functional role of IMP in the mechanics of the escape response. We simultaneously recorded the kinematics, muscle activity patterns and IMP of four A. calva and three P. palmas during the escape response. Both species generated high IMPs of up to 90 kPa (nearly 1 atmosphere) above ambient during the fast-start. The two species showed similar pressure magnitudes but had significantly different motor patterns and escape performance. Stage 1 of the fast-start was generated by simultaneous contraction of locomotor muscle on both sides of the body, although electromyogram amplitudes on the contralateral (convex) side of the fish were significantly lower than on the ipsilateral (concave) side. Simultaneous recordings of IMP, escape motion and muscle activity suggest that pressure change is caused by the contraction and radial swelling of cone-shaped myomeres. We develop a model of IMP production that incorporates myomere geometry, the concept of constant-volume muscular hydrostats, the relationship between fiber angle and muscle force, and the forces that muscle fibers produce. The timing profile of pressure change, behavior and muscle action indicates that elevated muscle pressure is a mechanism of stiffening the body and functions in force transmission during the escape response.


2019 ◽  
Vol 117 (38) ◽  
pp. 23286-23291 ◽  
Author(s):  
Jeffrey S. Dason ◽  
Amanda Cheung ◽  
Ina Anreiter ◽  
Vanessa A. Montemurri ◽  
Aaron M. Allen ◽  
...  

Painful or threatening experiences trigger escape responses that are guided by nociceptive neuronal circuitry. Although some components of this circuitry are known and conserved across animals, how this circuitry is regulated at the genetic and developmental levels is mostly unknown. To escape noxious stimuli, such as parasitoid wasp attacks,Drosophila melanogasterlarvae generate a curling and rolling response. Rover and sitter allelic variants of theDrosophila foraging(for) gene differ in parasitoid wasp susceptibility, suggesting a link betweenforand nociception. By optogenetically activating cells associated with each offor’s promoters (pr1–pr4), we show that pr1 cells regulate larval escape behavior. In accordance with rover and sitter differences in parasitoid wasp susceptibility, we found that rovers have higher pr1 expression and increased sensitivity to nociception relative to sitters. Thefornull mutants display impaired responses to thermal nociception, which are rescued by restoringforexpression in pr1 cells. Conversely, knockdown offorin pr1 cells phenocopies thefornull mutant. To gain insight into the circuitry underlying this response, we used an intersectional approach and activity-dependent GFP reconstitution across synaptic partners (GRASP) to show that pr1 cells in the ventral nerve cord (VNC) are required for the nociceptive response, and that multidendritic sensory nociceptive neurons synapse onto pr1 neurons in the VNC. Finally, we show that activation of the pr1 circuit during development suppresses the escape response. Our data demonstrate a role offorin larval nociceptive behavior. This function is specific toforpr1 neurons in the VNC, guiding a developmentally plastic escape response circuit.


1999 ◽  
Vol 77 (4) ◽  
pp. 671-674 ◽  
Author(s):  
William E Cooper, Jr.

Current models of optimal antipredation behavior do not apply to prey blocked by a predator from access to the primary refuge because the predator is closer than the optimal approach distance and flight toward the refuge would increase risk. If other alternative refuges are available, the prey should flee toward the best alternative one. I studied the effect of an approaching human simulated predator interposed between prey and refuge on the use of alternative refuges and on flight-initiation distance in the keeled earless lizard, Holbrookia propinqua. When the predator approached on a line between a lizard and its closest refuge, the lizard invariably fled to or toward an alternative refuge. Lizards were significantly more likely to use alternative refuges than lizards approached on a line connecting the closest refuge, prey, and predator, but with the lizard between the predator and the refuge. Flight-initiation distance was significantly greater for lizards having free access to the closest refuge than for those blocked from it, perhaps because of the time required to assess the new risk posed by blockage of the closest refuge, to select the best alternative refuge, or to wait for the predator to commit to a closing pattern before choosing the best flight option.


2018 ◽  
Vol 148 (2) ◽  
Author(s):  
Evelien Deboelpaep ◽  
Pieter-Jan Keleman ◽  
Bram Vanschoenwinkel ◽  
Nico Koedam

While escape responses are shown to differ in areas with varying levels of human disturbance, it is not known to what extent these reactions depend on the composition of local species assemblages. We investigated variation in three flight response metrics for the invasive Canada Goose (Branta canadensis) in Belgium in three locations with different human accessibility. Results indicate that heterospecific birds and flock size affected flight initiation distances of the Canada Goose, but that these effects are location-specific. Escape responses were most pronounced in the nature reserve with the lowest human accessibility, and highly reduced in the recreational park. This study illustrates that, when buffer zones are being developed, generalising escape behaviour of birds may lead to potentially dangerous overestimations of their tolerance to human disturbance.


2021 ◽  
Author(s):  
Hibiki Kimura ◽  
Tilo Pfalzgraff ◽  
Marie Levet ◽  
Yuuki Kawabata ◽  
John F Steffensen ◽  
...  

Fish perform rapid escape responses to avoid sudden predatory attacks. During escape responses, fish bend their bodies into a C-shape and quickly turn away from the predator and accelerate. The escape trajectory is determined by the initial turn (Stage 1) and a contralateral bend (Stage 2). Previous studies have used a single threat or model predator as a stimulus. In nature, however, multiple predators may attack from different directions simultaneously or in close succession. It is unknown whether fish are able to change the course of their escape response when startled by multiple stimuli at various time intervals. Pacific staghorn sculpin (Leptocottus armatus) were startled with a left and right visual stimulus in close succession. By varying the timing of the second stimulus, we were able to determine when and how a second stimulus could affect the escape response direction. Four treatments were used: a single visual stimulus (control); or two stimuli coming from opposite sides separated by a 0 ms (simultaneous treatment); a 33 ms; or a 83 ms time interval. The 33 ms and 83 ms time intervals were chosen to occur shortly before and after a predicted 60 ms visual escape latency (i.e. during Stage 1). The 0 ms and 33 ms treatments influenced both the escape trajectory and the Stage 1 turning angle, compared to a single stimulation, whereas the 83 ms treatment had no effect on the escape response. We conclude that Pacific staghorn sculpin can modulate their escape response only between stimulation and the onset of the response, but that escape responses are ballistic after the body motion has started.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5093 ◽  
Author(s):  
Yves Bötsch ◽  
Selina Gugelmann ◽  
Zulima Tablado ◽  
Lukas Jenni

Wildlife perceive humans as predators, and therefore normally flushes. Flight initiation distance (FID) is the distance a human can approach an animal at a steady pace until it flushes. Recently, several studies showed differences in within-species FID according to human presence by comparing urban and rural habitats, with urban birds showing reduced FIDs. However, urban and rural habitats also differ in structure, which might affect FID. Therefore, in order to understand the real effect of human presence, we investigated whether differences in FID are also present in natural habitats (forests), differing only in the intensity of human use for recreation. We found that human frequentation had a distinct effect on bird escape responses, with shorter FIDs in forests more-heavily frequented by humans than in forests rarely visited by humans. Whether this finding is driven by non-random spatial distribution of personalities (shy vs. bold) or phenotypic plasticity (habituation to humans) cannot be assessed with our data. Studies relying on FIDs should also incorporate human recreation intensity, as this affects the measurements strongly.


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