Raoul Mulder
Animal Behaviour Raoul Mulder
Learning 1
Learning The ability to draw on past experiences to adaptively adjust behaviour Learning is essential for survival and reproduction because it helps an animal adjust its behaviour to the state of its environment What to eat? Who to mate with? How to escape? When these responses are not genetically preprogrammed, they must be learnt 2
Opportunities for learning We often assume that learning is lifelong, but some behaviours can only be acquired during ‘critical’ periods Imprinting - ability to learn a specific essential piece of information at the right stage of development (the ‘critical’ period)
Konrad Lorenz
Imprinting shows that evolution can create a ‘window’ for learning key information about variation in the environment ...and his Greylag geese 3
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog Normal stimulus and response: Sight of food evokes salivation Food (natural stimulus)
Salivation
4
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog Neutral stimulus and response: No salivation Bell (conditioned stimulus)
5
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog
+ Bell
Food
Salivation
6
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog Conditioned response: Do has learned to salivate on hearing sound of bell Bell
Salivation
6
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Natural example:
Alarm calls Warning call ... Predator = Flee
7
Operant conditioning Voluntary behaviour is strengthened by reward and weakened by punishment Example:
Rat in a skinner box ‘Positive’ and ‘negative’ reinforcement help the animal to learn the correct response
8
Operant conditioning In the wild, adaptive aversions can result from similar mechanisms e.g. predators learning to avoid prey after distasteful experience
9
Social learning Learning that is influenced by observation of (or interaction with) other members of the same species (conspecifics) Example:
Many animals use social cues to locate food, and to learn to identify predators
10
Insight learning Tool use by New Caledonian crows Basis of tool use: Inherited species-typical action patterns Social learning Cultural transmission Insight learning
11
Answer: Ecological differences may select for differences in learning ability. 12
Adaptive differences in learning ability
Example:
seed-storing birds Nutcracker - stores many Scrub jay - stores fewer Spatial memory test nutcrackers perform best
Retention Interval (seconds)
Learning ability is shaped by natural selection and ecology
9,000 caches 30,000+ seeds
50
Nutcracker Mexican Jay
25
Pinyon Jay Scrub Jay
0
1
2 3 4 5 6
7 8 9 10 11 12 13 14 15 16 17
Block (n=100 trials)
13
Adaptive differences in learning ability Colour circle (non-spatial) test Pinyon jays perform best, nutcrackers second-worst Spatial learning abilities reflect ecological habits
Retention Interval (seconds)
50
Pinyon Jay Mexican Jay Nutcracker
25
0
Scrub Jay
5
10
15
20
25
30
Block (n=100 trials)
14
Learning evolution and trade-offs Can learning ability evolve under natural selection? Are there fitness cost associated with the evolution of learning?
15
Learning trade-offs Fruit flies trained to associate food types with an unpleasant chemical
After 47 generations, selected lines had improved learning ability
not conditioned conditioned to avoid orange
Proportion of eggs laid on orange
Lines bred from individuals able to discriminate
conditioned to avoid pineapple
0.8
0.4
Treatment
Control 16
Cost of learning high food 1
1
0
0
Competitive ability index
At low food levels, good learners were poorer competitors than poor learners
low food
good learners
poor learners
good learners
poor learners
17
Summary Many types of learning, and evidence for adaptive value of learning Species differ in learning ability due to differing ecological requirements Animals can evolve improved learning ability, but this can come at a cost trade-offs with other important functions such as competitive ability
18
PDF-Cita%ons Slide-1 !_MG_2581!peacock!spider!Maratus!volans!by!Jurgen!O=o!(h=p://www.flickr.com/photos/59431731@N05/5521738809/).!!Reproduced!with!permission!from!Jurgen!O=o. Slide-3 a)!(detail)!Konrad!Lorenz!(h=p://commons.wikimedia.org/wiki/File:Konrad_Lorenz.JPG)!by!Max!Planck!GesellschaV!(derivaWve!by!Eurobas)!(CC!BY\SA!3.0),!via!Wikimedia!Commons b)!(detail)!Greylag!Goose!by!David!Wright!CC!BY!2.0! Slide-4-17 Pavlov’s!dog!diagrams!by!Milly!Formby!©!University!of!Melbourne Slide-9 Skinner!box!scheme!01!(h=p://commons.wikimedia.org/wiki/File%3ASkinner_box_scheme_01.png)!By!Andreas1!(Adapted!from!Image:Boite!skinner.jpg)!(CC\BY\SA\3.0),!via!Wikimedia!Commons Slide-10 Bird!and!bu=erfly!by!Milly!Formby!©!University!of!Melbourne Slide-11 Poecilia!wingei!Campoma!Guppy!male!(h=p://commons.wikimedia.org/wiki/File%3APoecilia_wingei_Campoma_Guppy_male_008_en_20130428.jpg)!By!Emilio17!(Own!work)!(CC\BY\SA\3.0),!via!Wikimedia! Commons Slide-12 a)!Uek!on!stump!(ID#0037)! b)!Be=y!retrieving!bucket!with!wire!3!(ID#0004)!from!"Crow!Photos."!Behavioural+Ecology+Research+Group.!Web.!19!Aug.!2013.!.!!Reproduced!with! permission!from!Behavioural!Ecology!Research!Group,!Oxford!University. ! Slide-14 a)!Clark's!Nutcracker!Rocky!Mountain!NaWonal!Park!USA!(h=ps://commons.wikimedia.org/wiki/File%3AClark%27s_Nutcracker_Rocky_Mountain_NaWonal_Park_USA.jpg)!by!(WT\shared)!WineCountryInn!at!wts! wikivoyage!(CC\BY\SA\3.0),!via!Wikimedia!Commons b)!Fig.3!!by!Olson!DJ,!Kamil!AC,!Balda!RP,!Nims!PJ.!Performance!of!four!seed\caching!corvid!species!in!operant!tests!of!nonspaWal!and!spaWal!memory.!Journal+of+Compara9ve+Psychology.!1995;109(2):173\81.! Adapted!with!permission!from!the!American!Psychological!AssociaWon Slide-15 a)!Gymnorhinus!cyanocephalus1!by!Dave!Menke![Public!domain],!via!Wikimedia!Commons! b)!Fig.5!!by!Olson!DJ,!Kamil!AC,!Balda!RP,!Nims!PJ.!Performance!of!four!seed\caching!corvid!species!in!operant!tests!of!nonspaWal!and!spaWal!memory.!Journal+of+Compara9ve+Psychology.!1995;109(2):173\81.! Adapted!with!permission!from!the!American!Psychological!AssociaWon
21
Slide-16 Drosophila!melanogaster!couple!(h=p://commons.wikimedia.org/wiki/File%3ADrosophila.melanogaster.couple.2.jpg)!By!Sarefo!(Own!work)!(CC\BY\SA\3.0),!via!Wikimedia!Commons Slide-17 a)!Fruit!by!Milly!Formby!©!University!of!Melbourne b)!Graphs!by!Milly!Formby!based!on!data!from!Mery!F,!Kawecki!TJ.!Experimental!evoluWon!of!learning!ability!in!fruit!flies.!Proceedings+of+the+Na9onal+Academy+of+Science+USA.!99(22):14274\9. ! Slide-18 !!!!a)!Fruit!by!Milly!Formby!©!University!of!Melbourne b)Graphs!by!Milly!Formby!based!on!data!from!(Mery,!F!and!Kawecki,!T.!J)!A!fitness!cost!of!learning!ability!in!Drosophila!melanogaster.!!Proceedings+B!(2003)!270:!1532,!p2467.
22
Learning 1
Learning The ability to draw on past experiences to adaptively adjust behaviour Learning is essential for survival and reproduction because it helps an animal adjust its behaviour to the state of its environment What to eat? Who to mate with? How to escape? When these responses are not genetically preprogrammed, they must be learnt 2
Opportunities for learning We often assume that learning is lifelong, but some behaviours can only be acquired during ‘critical’ periods Imprinting - ability to learn a specific essential piece of information at the right stage of development (the ‘critical’ period)
Konrad Lorenz
Imprinting shows that evolution can create a ‘window’ for learning key information about variation in the environment ...and his Greylag geese 3
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog Normal stimulus and response: Sight of food evokes salivation Food (natural stimulus)
Salivation
4
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog Neutral stimulus and response: No salivation Bell (conditioned stimulus)
5
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog
+ Bell
Food
Salivation
6
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Example:
Pavlov’s dog Conditioned response: Do has learned to salivate on hearing sound of bell Bell
Salivation
6
Classical conditioning Reflexive response evoked by new (conditioned) stimulus that was originally evoked by a natural (unconditioned) stimulus Natural example:
Alarm calls Warning call ... Predator = Flee
7
Operant conditioning Voluntary behaviour is strengthened by reward and weakened by punishment Example:
Rat in a skinner box ‘Positive’ and ‘negative’ reinforcement help the animal to learn the correct response
8
Operant conditioning In the wild, adaptive aversions can result from similar mechanisms e.g. predators learning to avoid prey after distasteful experience
9
Social learning Learning that is influenced by observation of (or interaction with) other members of the same species (conspecifics) Example:
Many animals use social cues to locate food, and to learn to identify predators
10
Insight learning Tool use by New Caledonian crows Basis of tool use: Inherited species-typical action patterns Social learning Cultural transmission Insight learning
11
Answer: Ecological differences may select for differences in learning ability. 12
Adaptive differences in learning ability
Example:
seed-storing birds Nutcracker - stores many Scrub jay - stores fewer Spatial memory test nutcrackers perform best
Retention Interval (seconds)
Learning ability is shaped by natural selection and ecology
9,000 caches 30,000+ seeds
50
Nutcracker Mexican Jay
25
Pinyon Jay Scrub Jay
0
1
2 3 4 5 6
7 8 9 10 11 12 13 14 15 16 17
Block (n=100 trials)
13
Adaptive differences in learning ability Colour circle (non-spatial) test Pinyon jays perform best, nutcrackers second-worst Spatial learning abilities reflect ecological habits
Retention Interval (seconds)
50
Pinyon Jay Mexican Jay Nutcracker
25
0
Scrub Jay
5
10
15
20
25
30
Block (n=100 trials)
14
Learning evolution and trade-offs Can learning ability evolve under natural selection? Are there fitness cost associated with the evolution of learning?
15
Learning trade-offs Fruit flies trained to associate food types with an unpleasant chemical
After 47 generations, selected lines had improved learning ability
not conditioned conditioned to avoid orange
Proportion of eggs laid on orange
Lines bred from individuals able to discriminate
conditioned to avoid pineapple
0.8
0.4
Treatment
Control 16
Cost of learning high food 1
1
0
0
Competitive ability index
At low food levels, good learners were poorer competitors than poor learners
low food
good learners
poor learners
good learners
poor learners
17
Summary Many types of learning, and evidence for adaptive value of learning Species differ in learning ability due to differing ecological requirements Animals can evolve improved learning ability, but this can come at a cost trade-offs with other important functions such as competitive ability
18
PDF-Cita%ons Slide-1 !_MG_2581!peacock!spider!Maratus!volans!by!Jurgen!O=o!(h=p://www.flickr.com/photos/59431731@N05/5521738809/).!!Reproduced!with!permission!from!Jurgen!O=o. Slide-3 a)!(detail)!Konrad!Lorenz!(h=p://commons.wikimedia.org/wiki/File:Konrad_Lorenz.JPG)!by!Max!Planck!GesellschaV!(derivaWve!by!Eurobas)!(CC!BY\SA!3.0),!via!Wikimedia!Commons b)!(detail)!Greylag!Goose!by!David!Wright!CC!BY!2.0! Slide-4-17 Pavlov’s!dog!diagrams!by!Milly!Formby!©!University!of!Melbourne Slide-9 Skinner!box!scheme!01!(h=p://commons.wikimedia.org/wiki/File%3ASkinner_box_scheme_01.png)!By!Andreas1!(Adapted!from!Image:Boite!skinner.jpg)!(CC\BY\SA\3.0),!via!Wikimedia!Commons Slide-10 Bird!and!bu=erfly!by!Milly!Formby!©!University!of!Melbourne Slide-11 Poecilia!wingei!Campoma!Guppy!male!(h=p://commons.wikimedia.org/wiki/File%3APoecilia_wingei_Campoma_Guppy_male_008_en_20130428.jpg)!By!Emilio17!(Own!work)!(CC\BY\SA\3.0),!via!Wikimedia! Commons Slide-12 a)!Uek!on!stump!(ID#0037)! b)!Be=y!retrieving!bucket!with!wire!3!(ID#0004)!from!"Crow!Photos."!Behavioural+Ecology+Research+Group.!Web.!19!Aug.!2013.!.!!Reproduced!with! permission!from!Behavioural!Ecology!Research!Group,!Oxford!University. ! Slide-14 a)!Clark's!Nutcracker!Rocky!Mountain!NaWonal!Park!USA!(h=ps://commons.wikimedia.org/wiki/File%3AClark%27s_Nutcracker_Rocky_Mountain_NaWonal_Park_USA.jpg)!by!(WT\shared)!WineCountryInn!at!wts! wikivoyage!(CC\BY\SA\3.0),!via!Wikimedia!Commons b)!Fig.3!!by!Olson!DJ,!Kamil!AC,!Balda!RP,!Nims!PJ.!Performance!of!four!seed\caching!corvid!species!in!operant!tests!of!nonspaWal!and!spaWal!memory.!Journal+of+Compara9ve+Psychology.!1995;109(2):173\81.! Adapted!with!permission!from!the!American!Psychological!AssociaWon Slide-15 a)!Gymnorhinus!cyanocephalus1!by!Dave!Menke![Public!domain],!via!Wikimedia!Commons! b)!Fig.5!!by!Olson!DJ,!Kamil!AC,!Balda!RP,!Nims!PJ.!Performance!of!four!seed\caching!corvid!species!in!operant!tests!of!nonspaWal!and!spaWal!memory.!Journal+of+Compara9ve+Psychology.!1995;109(2):173\81.! Adapted!with!permission!from!the!American!Psychological!AssociaWon
21
Slide-16 Drosophila!melanogaster!couple!(h=p://commons.wikimedia.org/wiki/File%3ADrosophila.melanogaster.couple.2.jpg)!By!Sarefo!(Own!work)!(CC\BY\SA\3.0),!via!Wikimedia!Commons Slide-17 a)!Fruit!by!Milly!Formby!©!University!of!Melbourne b)!Graphs!by!Milly!Formby!based!on!data!from!Mery!F,!Kawecki!TJ.!Experimental!evoluWon!of!learning!ability!in!fruit!flies.!Proceedings+of+the+Na9onal+Academy+of+Science+USA.!99(22):14274\9. ! Slide-18 !!!!a)!Fruit!by!Milly!Formby!©!University!of!Melbourne b)Graphs!by!Milly!Formby!based!on!data!from!(Mery,!F!and!Kawecki,!T.!J)!A!fitness!cost!of!learning!ability!in!Drosophila!melanogaster.!!Proceedings+B!(2003)!270:!1532,!p2467.
22
