Animal Cognition Lecture 2 Perception & Concept Formation Clive D. L. Wynne
Vision in Birds: UV HumanBird, bee…
Vision in birds: 6 color channels Retinal anatomy: Absorption of light by photopigments
Vision in birds: 6 color channels Behavior: Wavelength discrimination functions
Vision in birds: Polarization Pigeons are sensitive to the direction of polarization of the sun’s light
Smell Enables detection of low concentrations of chemicals over distances Important for finding food also communication (pheromones) Insects: Wasps find caterpillars on plants; honeybees find flowers; male Currant clearwings attracted to female pheromone
Smell Dogs! Turkish hamsters recognize different brothers’ smells Female house mouse prefer odor of male mice from near home; when sexually receptive prefer odor of dominant male mouse Female bank voles abort pregnancy if smell non-father male Hedgehogs prefer forage at sites contaminated by chipmunks (not predators) to badgers (predators). Pigeons use smell in navigation
Hearing Birds (owls, harriers) and humans can localize sound source to 2º out of 360º Eastern towhees estimate distance with error of 7% and direction error 9º. Territorial – played calls of other male towhees. Rodents have good low frequency hearing (< 150 Hz). Bats and dolphins hear up to 100 kHz Humans 100 Hz 20 kHz
Hearing in bats
Weakly electric African fish
Magnetic sensitivity Honeybees can be trained to select food container on top of a magnetic in preference to less food (in identical container) not placed on a Magnet (Walker & Bitterman, 1985). Migrating fish may use magnetic fields Magnetite in heads of monarch butterflies.
Pigeon homing: Magnetic Compass Pigeon homing is disturbed by sunspot activity (which upsets the earth’s magnetic field), magnetic storms local magnetic anomalies.
Pigeon homing: Magnetic Compass clockwise currentanticlockwise current sunny day overcast day S W E N
Pigeon homing: Magnetic Compass clockwise currentanticlockwise current sunny day overcast day S W E N
Perceptual concepts Easy positive Hard positive Easy negativeHard negative
Animal Number Sense Clever Hans Relative number: Few vs. more Absolute number Counting
Relative number
Absolute number
Counting 1.Tagging: A certain number name or tag goes with a certain quantity of items. ‘1’ stands for a single item. 2.Cardinality: Tag applied to the last item of a set is the name for the number of items in that set.
Counting: Ai (chimp) Ai Counting Ai Counting with memory Ai vs. humans
Counting: Brannon & Terrace (macaques)