F exam 2 F learning in a natural environment F special case... flower learning F odor learning in the proboscis extension reflex F summary PART 4: BEHAVIORAL PLASTICITY #18: ASSOCIATIVE LEARNING IN HONEYBEES I

F exam 2 F learning in a natural environment F special case... flower learning F odor learning in the proboscis extension reflex F summary PART 4: BEHAVIORAL PLASTICITY #18: ASSOCIATIVE LEARNING IN HONEYBEES I

EXAM 2

MULTIPLE CHOICE vs WRITTEN EXAMS  …   … ……   …  

F order Hymenoptera, family Apidae, Apis melifera F haplo-diploid: queen, haploid drones, sterile workers HONEYBEES

F originate in S. Asia, now ~ cosmopolitan F live in highly social, permanent colonies F hive population... 5K to 35K, max 60K workers HONEYBEES

F life cycle HONEYBEES

F forage for pollen (protein) & nectar (carbohydrate) F fantastic learners F encode complex environmental features in seconds... F remembers it for lifetime F small brain – about 1 mm 3 = ~ neurons HONEYBEES

F breeding F honey F sting defense F Africanized HONEYBEES

F types of worker bees F cleaners F nurses F hive, undertakers F guards F recruits F foragers F scouts LEARNING IN THE NATURAL ENVIRONMENT

F carry pollen & nectar in pollen sacks on hind legs F deposit in hive, communicate with recruits LEARNING IN THE NATURAL ENVIRONMENT

F foraging cycle F flight out F at food source F flight back F waggle dance LEARNING IN THE NATURAL ENVIRONMENT

F foraging cycle F flight out – visual memory of environment F hover at hive F landmarks during flight F use sun and polarized light F at food source F flight back F waggle dance LEARNING IN THE NATURAL ENVIRONMENT

F foraging cycle F flight out F at food source – visual memory of environment F recruits – have olfactory memory of flower F foragers remember physical features of flowers F flight back F waggle dance LEARNING IN THE NATURAL ENVIRONMENT

F foraging cycle F flight out F at food source F flight back – visual memory of environment F can be several miles F also use “vector memory” F waggle dance LEARNING IN THE NATURAL ENVIRONMENT

F foraging cycle F flight out F at food source F flight back F waggle dance F scout encodes food / sun relationship LEARNING IN THE NATURAL ENVIRONMENT

F foraging cycle F flight out F at food source F flight back F waggle dance hive, dances on comb surface (~ language!) F nectar & odor  recruits (~ reward?) F content, distance & direction of flower patch F experiments with robot bee dancers F also for communicating potential new hive site LEARNING IN THE NATURAL ENVIRONMENT

F flower constancy: bees tend to prefer 1 type of flower F can distinguish 1 flower from another F what physical attibutes? F color? F odor? FLOWER LEARNING

F test associating color with reward F feeding station with honey solution F train on 1 color (blue, pink in picture) F test on others F remember paired color FLOWER LEARNING

F illuminated disc experiment F train bees to feed with no illuminated disc F test with two different colors, measure preferences F adjust intensity to = F trained & tested on “normalized” colors FLOWER LEARNING

F learning curves for different wavelengths of light F bees learn F violet best F others less F blue-green worst FLOWER LEARNING

F how long do bees remember? F train: blue light + sucrose F test blue vs yellow F 1 trial training... F stable memory for days F 3 trial training... F permanent memory FLOWER LEARNING

F how long do bees remember? F train: blue light + sucrose F test blue vs yellow F stable memory for days F strength different when measured at different times after training F ecological implications FLOWER LEARNING

F timing of stimuli + reward critical F color turned on at different times during training F learn color in short time window F 3 s before landing F  2 s after landing F before reward FLOWER LEARNING

F timing of stimuli + reward critical F color turned on at different times during training F learn color in short time window F 3 s before landing F  2 s after landing F before reward F sensory memory F ignore later colors FLOWER LEARNING

F not only color, shapes & patterns can also be learned F all features  integrated whole F change 1 feature ( e.g., odor)  entirely new “flower” F all other features need to be relearned F context important FLOWER LEARNING

F not only color, shapes & patterns can also be learned F bees learn complementary patterns... FLOWER LEARNING

F not only color, shapes & patterns can also be learned F bees learn symmetry of patterns... FLOWER LEARNING

F not only color, shapes & patterns can also be learned F bees learn symmetry of patterns... F trained on patterns... for either F symmetrical F asymmetrical FLOWER LEARNING

F not only color, shapes & patterns can also be learned F bees learn symmetry of patterns... F trained on patterns... for either F symmetrical F asymmetrical F tested on patterns... either F symmetrical F asymmetrical FLOWER LEARNING

F not only color, shapes & patterns can also be learned F bees learn symmetry of patterns... F learned according to F choice frequency F proximity to correct choice F amount of time at correct choice F what is going on in the brain? FLOWER LEARNING

BREAK … but first …