“Animal behavior is the bridge between
the molecular and physiological aspects
of biology and the ecological. Behavior
is the link between organisms and the
environment and between the nervous
system and the ecosystem.”
-Charles Snowdon
Tinbergen’s Four Questions
1. “How does it work?”
3. “What is it for?”
Sensory-motor mechanisms
Function/adaptation –
usefulness in survival and
reproduction
2. “How did it develop?”
4. “How did it evolve?”
Genetic-developmental
mechanisms
Evolution – the historical
pathway leading to the
current trait
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
3. Function/adaptation
2. Genetic-developmental mechanisms
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
3. Function/adaptation
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
3. Function/adaptation
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
3. Function/adaptation
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
-So the direction and distance of
migration is under genetic control
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
3. Function/adaptation
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
-So the direction and distance of
migration is under genetic control
-Morphological differences are under
genetic control
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
-So the direction and distance of
migration is under genetic control
-Morphological differences are under
genetic control
3. Function/adaptation
-90% overwinter in Spain for foraging
purposes (natural food sources)
-10% overwinter in Britain (artificial
food sources)
-Breeding habitat is in Germany
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
-So the direction and distance of
migration is under genetic control
-Morphological differences are under
genetic control
3. Function/adaptation
-90% overwinter in Spain for foraging
purposes (natural food sources)
-10% overwinter in Britain (artificial
food sources)
-Breeding habitat is in Germany
-British group has narrower, longer
beaks, rounder wings, and browner
colouration
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
-So the direction and distance of
migration is under genetic control
-What caused the change in migration?
-Morphological differences are under
genetic control
3. Function/adaptation
-90% overwinter in Spain for foraging
purposes (natural food sources)
-10% overwinter in Britain (artificial
food sources)
-Breeding habitat is in Germany
-British group has narrower, longer
beaks, rounder wings, and browner
colouration
4. Evolution
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
-Hybrids between the two groups show
intermediate migratory behaviour....
-So the direction and distance of
migration is under genetic control
-What caused the change in migration?
-Morphological differences are under
genetic control
3. Function/adaptation
-90% overwinter in Spain for foraging
purposes (natural food sources)
-10% overwinter in Britain (artificial
food sources)
-Breeding habitat is in Germany
-British group has narrower, longer
beaks, rounder wings, and browner
colouration
4. Evolution
-How has the change in migratory
behaviour affected other aspects of
biology?
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
3. Function/adaptation
-90% overwinter in Spain for foraging
purposes (natural food sources)
-10% overwinter in Britain (artificial
food sources)
-Breeding habitat is in Germany
-British group has narrower, longer
beaks, rounder wings, and browner
colouration
4. Evolution
-How has the change in migratory
-Hybrids between the two groups show
behaviour affected other aspects of
intermediate migratory behaviour....
biology?
-So the direction and distance of
migration is under genetic control
-What are the long-term evolutionary
-What caused the change in migration?
implications?
-Morphological differences are under
genetic control
Tinbergen’s Four Questions
1. Sensory-motor mechanisms
-No information is provided about
how blackcaps navigate or what cues
trigger migration, so there is probably
no expectation for you to discuss this
level.
2. Genetic-developmental mechanisms
3. Function/adaptation
-90% overwinter in Spain for foraging
purposes (natural food sources)
-10% overwinter in Britain (artificial
food sources)
-Breeding habitat is in Germany
-British group has narrower, longer
beaks, rounder wings, and browner
colouration
4. Evolution
-How has the change in migratory
-Hybrids between the two groups show
behaviour affected other aspects of
intermediate migratory behaviour....
biology?
-So the direction and distance of
migration is under genetic control
-What are the long-term evolutionary
-What caused the change in migration?
implications?
-Morphological differences are under
genetic control
-Why do you think hybrids are rare?
1. Sensory-motor mechanisms: navigation
The star compass (plus the sun, landmarks, polarised light, magnetic fields...)
2. Genetic-developmental mechanisms:
Innate and learned travel plans
Photo: Sergey Yeliseev
• starlings: 11,500 individuals shifted 500km
during autumn migration
• adult birds corrected for the shift
• young birds didnʼt make corrections
2. Genetic-developmental mechanisms:
genetics influence the desire to migrate,
the direction and distance of migration
Photo: S. Yeliseev
2. Genetic-developmental mechanisms:
genetics govern beak shape/length,
wing shape, colour of beak and plumage
Photo: S. Yeliseev
3. Function:
All behaviours have costs and benefits
energy food
risk of injury
access to mates
risk of predation
protect relatives
8
time healthy young
3. Function of migration:
Tradeoffs between survival and
reproductive success
Migrant
!
Resident
Annual
Adult
Survival
MODERATE! !
(50%)! !
!
LOW
(20-50%)
Annual
Reproductive
Success
MODERATE! !
HIGH
Adapted from Gill (1990)
3. Function of migration:
Tradeoffs for migrating blackcaps
Photo: Augustín Povedano
3. Function of morphological changes:
Adaptation to new foods and selection
pressures in Britain
Photo: Donna [email protected]
4. Evolution: Why has migratory behaviour
changed now?
Photos: Tony Morris
4. Evolution: Why has migratory behaviour
changed now?
Photos: Tony Morris
4. Evolution: How has the change in
migratory behaviour affected other
aspects of blackcap biology?
Photo: Mark Kilner
4. Evolution: What are the evolutionary
implications?
♀
♂
Photo: Alberto Garcia