Multiple functions of extraoral lingual behaviour in iguanian lizards: prey capture, grooming and swallowing, but not prey detection

We examined the effects of water velocity on prey detection and capture by drift-feeding juvenile coho salmon (Oncorhynchus kisutch) and steelhead (sea-run rainbow trout, Oncorhynchus mykiss irideus) in laboratory experiments. We used repeated-measures analysis of variance to test the effects of velocity, species, and the velocity × species interaction on prey capture probability, prey detection distance, and swimming speeds during prey capture. We used 3D video analysis to assess the spatial and temporal characteristics of prey detection and capture. Coho and steelhead showed significant, velocity-dependent decreases in capture probability (~65% to 10%, with an increase of velocity from 0.29 to 0.61 m·s-1) and prey detection distance, with no effect of species and no velocity × species interaction. Neither velocity nor species affected prey interception speed; fish intercepted prey at their predicted maximum sustainable swimming speed (Vmax) at all velocities. Speed of return to the focal point increased significantly with increasing velocity, with no effect of species. At faster velocities, return speeds were faster than Vmax, indicating potential increases in energetic cost because of anaerobic swimming. The 3D analysis suggests that the reduction in capture probability was due to both reduced prey detection distance and a uniform decline in detection probability within the prey capture area.

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Prey Detection and Prey Capture in Copepod Nauplii

PLoS ONE ◽

10.1371/journal.pone.0047906 ◽

2012 ◽

Vol 7 (10) ◽

pp. e47906 ◽

Cited By ~ 23

Author(s):

Eleonora Bruno ◽

Christian Marc Andersen Borg ◽

Thomas Kiørboe

Keyword(s):

Prey Capture ◽

Prey Detection

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Prey detection in selective plankton feeding by the paddlefish: is the electric sense sufficient?

Journal of Experimental Biology ◽

10.1242/jeb.204.8.1381 ◽

2001 ◽

Vol 204 (8) ◽

pp. 1381-1389 ◽

Cited By ~ 2

Author(s):

L.A. Wilkens ◽

B. Wettring ◽

E. Wagner ◽

W. Wojtenek ◽

D. Russell

Keyword(s):

Prey Capture ◽

General Pattern ◽

Background Concentration ◽

Prey Detection ◽

Sensory Cues ◽

Flow Conditions ◽

Observation Chamber ◽

High Background ◽

Turbulent Water ◽

Sensory Mechanisms

The long rostrum of the paddlefish Polyodon spathula supports an extensive array of ampullary electroreceptors and has been proposed to function as an antenna for detecting planktonic prey. Evidence in support of this hypothesis is presented in experiments that preclude the use of other sensory mechanisms for plankton detection. Paddlefish swimming in a recirculating observation chamber are shown to feed normally in the dark when prey-related chemical and hydrodynamic sensory cues are masked or attenuated. Specifically, we demonstrate that the spatial distribution of plankton captured by paddlefish is little changed when the plankton are individually encapsulated in agarose, when a high background concentration of plankton extract is added to the chamber, when the nares are plugged and under turbulent water flow conditions. Paddlefish also discriminate between encapsulated plankton and ‘empty’ agarose particles of the same size. Although capture distributions differed somewhat under certain conditions, the general pattern and effectiveness of prey capture were not disrupted by these procedures. These results support the conclusion that paddlefish, as zooplanktivores, rely on their passive electric sense for prey detection.

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Prey detection in a cruising copepod

Biology Letters ◽

10.1098/rsbl.2011.1073 ◽

2011 ◽

Vol 8 (3) ◽

pp. 438-441 ◽

Cited By ~ 21

Author(s):

Sanne Kjellerup ◽

Thomas Kiørboe

Keyword(s):

Boundary Layer ◽

Chemical Cues ◽

Prey Capture ◽

Reynolds Numbers ◽

Prey Detection ◽

Potential Prey ◽

Viscous Boundary Layer ◽

Low Reynolds Numbers ◽

Low Reynolds ◽

Viscous Boundary

Small cruising zooplankton depend on remote prey detection and active prey capture for efficient feeding. Direct, passive interception of prey is inherently very inefficient at low Reynolds numbers because the viscous boundary layer surrounding the approaching predator will push away potential prey. Yet, direct interception has been proposed to explain how rapidly cruising, blind copepods feed on non-motile phytoplankton prey. Here, we demonstrate a novel mechanism for prey detection in a cruising copepod, and describe how motile and non-motile prey are discovered by hydromechanical and tactile or, likely, chemical cues, respectively.

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Contrast, contours and the confusion effect in dazzle camouflage

Royal Society Open Science ◽

10.1098/rsos.160180 ◽

2016 ◽

Vol 3 (7) ◽

pp. 160180 ◽

Cited By ~ 13

Author(s):

Benedict G. Hogan ◽

Nicholas E. Scott-Samuel ◽

Innes C. Cuthill

Keyword(s):

Prey Capture ◽

Moving Target ◽

Previous Evidence ◽

Multiple Functions ◽

Confusion Effect ◽

Potential Motion ◽

Surface Patterns ◽

Human Participants ◽

Motion Dazzle ◽

Camouflage Patterns

‘Motion dazzle camouflage’ is the name for the putative effects of highly conspicuous, often repetitive or complex, patterns on parameters important in prey capture, such as the perception of speed, direction and identity. Research into motion dazzle camouflage is increasing our understanding of the interactions between visual tracking, the confusion effect and defensive coloration. However, there is a paucity of research into the effects of contrast on motion dazzle camouflage: is maximal contrast a prerequisite for effectiveness? If not, this has important implications for our recognition of the phenotype and understanding of the function and mechanisms of potential motion dazzle camouflage patterns. Here we tested human participants' ability to track one moving target among many identical distractors with surface patterns designed to test the influence of these factors. In line with previous evidence, we found that targets with stripes parallel to the object direction of motion were hardest to track. However, reduction in contrast did not significantly influence this result. This finding may bring into question the utility of current definitions of motion dazzle camouflage, and means that some animal patterns, such as aposematic or mimetic stripes, may have previously unrecognized multiple functions.

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Activation of the hypothalamic feeding centre upon visual prey detection

10.1101/078527 ◽

2017 ◽

Author(s):

Akira Muto ◽

Pradeep Lal ◽

Deepak Ailani ◽

Gembu Abe ◽

Mari Itoh ◽

...

Keyword(s):

Visual Information ◽

Prey Capture ◽

Prey Detection ◽

Hypothalamic Area ◽

Zebrafish Larvae ◽

Prey Recognition ◽

Food Detection ◽

Feeding Motivation ◽

Freely Behaving ◽

Pretectal Area

The visual system plays a major role in food/prey recognition in diurnal animals, and food intake is regulated by the hypothalamus. However, whether and how visual information about prey is conveyed to the hypothalamic feeding centre is largely unknown. Here we perform real-time imaging of neuronal activity in freely behaving or constrained zebrafish larvae and demonstrate that prey or prey-like visual stimuli activate the hypothalamic feeding centre. Furthermore, we identify prey detector neurons in the pretectal area that project to the hypothalamic feeding centre. Ablation of the pretectum completely abolishes prey capture behaviour and neurotoxin expression in the hypothalamic area also reduces feeding. Taken together, these results suggest that the pretecto-hypothalamic pathway plays a crucial role in conveying visual information to the feeding centre. Thus, this pathway possibly converts visual food detection into feeding motivation in zebrafish.

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The effect of prey availability on metabolism and activity in the tarantula Phormictopus cancerides

Canadian Journal of Zoology ◽

10.1139/z09-122 ◽

2010 ◽

Vol 88 (1) ◽

pp. 90-98 ◽

Cited By ~ 9

Author(s):

B. N. Philip ◽

C. Shillington

Keyword(s):

Prey Capture ◽

Prey Availability ◽

Locomotory Activity ◽

Prey Detection ◽

Metabolic Rates ◽

Feeding Trial ◽

Detection Distance ◽

Feeding Behaviors ◽

Limited Food ◽

Feeding Trials

Spiders typically exhibit very low resting metabolic rates (RMR) and altered feeding behaviors as mechanisms to survive extended periods of limited food availability. We examined the effect of different periods of food deprivation on RMR and foraging activities in the Hispaniolan giant tarantula ( Phormictopus cancerides (Latreille, 1806)) (Araneae: Theraphosidae). Juvenile tarantulas were separated into two feeding groups and fed once either every 5 or 30 days. Monthly feeding trials were preceded by RMR measurements. During feeding trials, we compared differences between the two groups in (i) prey capture frequency, (ii) time to prey capture, (iii) locomotory activity, and (iv) the predator’s prey detection distance. Metabolic rates increased for the well-fed group but remained constant for individuals fed once a month. Time to prey capture decreased for food-limited individuals and the proportion of individuals that ate during each feeding trial was significantly higher in the 30-day group. Conversely, results for locomotory activity and detection distances were inconclusive.

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Second-order cues to figure motion enable object detection during prey capture by praying mantises

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1912310116 ◽

2019 ◽

Vol 116 (52) ◽

pp. 27018-27027 ◽

Cited By ~ 2

Author(s):

Vivek Nityananda ◽

James O’Keeffe ◽

Diana Umeton ◽

Adam Simmons ◽

Jenny C. A. Read

Keyword(s):

Motion Detection ◽

Prey Capture ◽

Second Order ◽

Prey Detection ◽

Motion Sensitivity ◽

Motion Cues ◽

First Order ◽

Motion Detectors ◽

Do So

Detecting motion is essential for animals to perform a wide variety of functions. In order to do so, animals could exploit motion cues, including both first-order cues—such as luminance correlation over time—and second-order cues, by correlating higher-order visual statistics. Since first-order motion cues are typically sufficient for motion detection, it is unclear why sensitivity to second-order motion has evolved in animals, including insects. Here, we investigate the role of second-order motion in prey capture by praying mantises. We show that prey detection uses second-order motion cues to detect figure motion. We further present a model of prey detection based on second-order motion sensitivity, resulting from a layer of position detectors feeding into a second layer of elementary-motion detectors. Mantis stereopsis, in contrast, does not require figure motion and is explained by a simpler model that uses only the first layer in both eyes. Second-order motion cues thus enable prey motion to be detected, even when perfectly matching the average background luminance and independent of the elementary motion of any parts of the prey. Subsequent to prey detection, processes such as stereopsis could work to determine the distance to the prey. We thus demonstrate how second-order motion mechanisms enable ecologically relevant behavior such as detecting camouflaged targets for other visual functions including stereopsis and target tracking.

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Defined cell types in superior colliculus make distinct contributions to prey capture behavior in the mouse

10.1101/626622 ◽

2019 ◽

Cited By ~ 2

Author(s):

Jennifer L. Hoy ◽

Hannah I. Bishop ◽

Cristopher M. Niell

Keyword(s):

Superior Colliculus ◽

Neural Circuit ◽

Prey Capture ◽

Cell Types ◽

Wide Field ◽

List Type ◽

Prey Detection ◽

Approach Behavior ◽

And Function

SummaryThe superior colliculus (SC) mediates rapid orienting to visual stimuli across species. To determine the specific circuits within the SC that drive orienting and approach behavior toward appetitive stimuli, we explored the role of three genetically defined cell types in mediating prey capture in mice. Chemogenetic inactivation of two classically defined cell types, the wide-field (WF) and narrow-field (NF) vertical neurons, revealed that they are involved in distinct aspects of prey capture. WF neurons were required for rapid prey detection and distant approach initiation, whereas NF neurons were required for continuous and accurate orienting during pursuit. In contrast, prey capture did not require parvalbumin-expressing (PV) neurons that have previously been implicated in fear responses. The visual coding of WF and NF cells in the awake mouse and their projection targets were consistent with their roles in prey detection versus pursuit. Thus, our studies link specific neural circuit connectivity and function with stimulus detection and orienting behavior, providing insight into visuomotor and attentional mechanisms mediated by superior colliculus.HighlightsThis study provides the first demonstration of the role of specific cell populations in the superior colliculus in orienting and approach behavior.A genetically targeted population of wide-field vertical neurons in the superior colliculus is required for rapid prey detection and initiation of long-distance approaches.A genetically targeted population of narrow-field vertical neurons is required for approach initiation, accurate targeting, and approach continuity.Visual response properties and projection targets of these cells are consistent with their role in prey capture, linking neural circuit connectivity and function with behavior.

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A persistent behavioral state enables sustained predation of humans by mosquitoes

10.1101/2021.10.06.463436 ◽

2021 ◽

Author(s):

Trevor R Sorrells ◽

Anjali Pandey ◽

Adriana Rosas-Villegas ◽

Leslie B Vosshall

Keyword(s):

Carbon Dioxide ◽

Blood Meal ◽

Prey Capture ◽

Internal State ◽

Behavioral State ◽

Prey Detection ◽

Sensory Cues ◽

Initial Stimulus ◽

Visual Contrast ◽

Long Timescales

Predatory animals first detect, then pursue, and ultimately capture prey. Sensory cues, including scent emitted by prey, are detected by the predator and used to guide pursuit. Because the pursuit phase can last for extended periods of time, it is critical for predators to persist in the chase even when prey is difficult to detect in a noisy sensory land-scape. It is equally important for predators to abandon pursuit if enough time has elapsed that prey capture is unlikely to occur. We studied prey detection and sustained pursuit in the mosquito Aedes aegypti, a micropredator of humans. These animals first detect hu-mans through sensory cues that are emitted at a distance such as carbon dioxide in breath and odor from skin. As the mosquito approaches a human, additional cues such as body heat and visual contrast signal the promise of a blood meal, which females need to produce eggs. To study how initial prey detection influences the duration of pursuit, we developed optogenetic tools to induce a brief fictive sensation of carbon dioxide and used machine learning-based classification of behavior to investigate how mosquitoes respond to subsequent human cues. We found that a 5-second optogenetic pulse of fictive carbon dioxide induced a persistent behavioral state in female mosquitoes that lasted for more than 10 minutes. This state is highly specific to females searching for a blood meal and was not induced in recently blood-fed females or in males, who do not feed on blood. In males that lack the gene fruitless, which controls persistent social behaviors in other insects, fictive carbon dioxide induced a long-lasting behavior response resembling the predatory state of females. Finally, we show that the persistent state triggered by detection of fictive carbon dioxide enabled females to engorge on a blood meal mimic offered up to 14 minutes after the initial stimulus. Our results demonstrate that a persistent internal state allows female mosquitoes to integrate multiple human sensory cues over long timescales, an ability that is key to their success as an apex micropredator of humans

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