Predator-Prey Mechanisms
Richard G. Coss
ANB 218B
Winter 2010
Levels of Organization
Steven Pepper’s Mechanism Construct
Heterochrony
Neotenous properties of the human face
Perceptual Aspects of Predator Recognition
• Developmental and neurobiological aspects of eyespot recognition by African jewel fish
• Genetic and experiential effects of eyespot recognition by paradise fish
• Crab predator recognition by climbing crabs• Development of ground squirrel recognition of
snake predators
Innate Eyespot Recognition by Jewel Fish
Eyespot Models
Jewel Fish Fry Pre-flight Position
Jewel Fish Fry Fleeing Eyespot Model
Generalization gradient of eyespot number
Juvenile Jewel Fish Model Presentation
Juvenile Jewel Fish Flight Distance Measure
Generalization gradient of eyespot number
Test of eyespot pattern orientation
Generalization gradient of eyespot orientation
Deprivation rearing of African jewel fish
Jewel fish inspecting blind cave fish
Jewel fish view of blind cave fish
Generalization gradients of rearing conditions
Neuroanatomical correlates of eyespot recognition by African jewel fish and ground squirrel antisnake behavior
• At 13 post-spawning days of age when fry first employ visually guided behavior to feed and recognize eyespots as dangerous, they also exhibit recognizable neurons in the optic tectum developmentally similar to those of adults.
• Developmental deprivation of jewel fish fry to when they are adults affects neuron development within the optic tectum and the retention of juvenile reactivity to eyespot patterns.
• Discussion of rat brain development when pups begin to see is relevant to understanding precocious snake predator recognition by ground squirrels pups.
Optic tectum development
Neurological effects of isolation rearing
Experimental study of eyespot pattern recognition by Asian paradise fish
Miklosi et al. 1997 Behavior Genetics
• Comparison of two larval strains in eyespot pattern recognition
• Comparison of two genetic strains that differ in eyespot pattern recognition
• Role of father in aiding the development of eyespot pattern recognition
Eyespot recognition by paradise fish
Miklosi et al. 1997 Behavior Genetics
Larva (10 mm long) tested at 20 days of age
Eyespot recognition by paradise fish
Genetic differences in eyespot recognition
Fathered group of paradise fish
Father fans egg mass for 5 post-spawning days.Larva in this group are tested at 20 days of age.
Role of egg-mass fanning by father
Perceptual aspects of crab predator recognition by climbing crabs
Cannicci et al. 2002 Anim. Beh.
Predator Models
1) Preserved crab Epixanthus dentatus in its typical ambush posture
2) Colored piece of wood with real E. dentatus claws attached to it
3) Colored piece of wood without claws
Predator crab recognition by climbing crab
Brachyuran predator
Cannicci et al. 2002 Anim. Beh.
Mangrove tree test bridge
Descending crab prey
Crab model
Responses of climbing crabs to models
Precocious development of snake predator recognition by California ground squirrels
Coss 1991 Ecol. Psych.
• Developmental onset of snake recognition in pre-emergent ground squirrel pups at 40-41 days of age.
• Precocious snake recognition is a by-product of high gene expression during the time of eye opening in pups.
• Gopher snake perceptual feature recognition. • Recognition of burrows as sit and wait snake ambush sites
after interactions with snakes in the field and lab.• Role of alarm calling in promoting snake recognition in
developmentally deprived ground squirrel adults.
Northern Pacific rattlesnake
Ground squirrel harassing rattlesnake
Pup recognizes rattlesnake immediately as it emerges the first time from its natal burrow
Pup confronts rattlesnake in artificial burrow
Pre-emergent ground squirrel pup recognizes gopher snake as dangerous the first day its uses vision at 40 days of age.
41 day-old pup cautiously investigates a textured strip resembling gopher snake scale markings the first day it uses vision.
Developmental changes in ground squirrel pup responsiveness to caged gopher snake and textured strip between 41 and
46 days of age.
Rat brain development when pups first see as an analog for ground squirrel neural development with the onset of vision
Effects of developmental deprivation in rats
Greenough et al.1972 Science
Cognitive Topography
Coss & Owings 1985
Coss & Goldthwaite 1995
• Ground squirrels appear to recognize what microhabitat features predators might use for sit and wait ambushing.
• Ground squirrels are deprived for 3 years after weaning for experimental study of alarm call recognition.
• Lab-born ground squirrels innately associate dark burrow entrances with snakes that use them for ambushing and thermoregulation.
Rock squirrel from New Mexico cautiously investigates a burrow entrance after a rattlesnake encounter
Historical risk of encountering rattlesnakes in shady areas
Historical risks of encountering rattlesnakes in burrow entrances
Rattlesnake resting in burrow entrance
Lab-born juvenile throws substrate into the dark entrance of its transfer box after encountering a caged gopher snake
Historical risks of avian and mammalian predatorsbased on distance from refuge
Effects of alarm call playbacks on surveillance during burrow exiting
Ground squirrels pausing during nestbox exciting to look upward and horizontally
Average duration of looking and sniffing after nestbox exiting following sound treatments
Lab-born ground squirrels shows concern for possible snake in nestbox following alarm call playbacks
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