(1) must know prior history
(2) experiment must be designed to avoid practice
(3) animal must be able to view whole s.8 = prior to testing
(4) can’t exclude ‘chance’ solutions
(6) Imprinting
- rapid learning process
- early dev.
- long-lasting results
- first demonstrated by K. Lorenz
-
- imprinted on first moving object
Two general classes
(A) object imprinting
(B) motoric imprinting
(A) Object Imprinting
i) Parental (Filial) imprinting
- seen most strongly
- in precocial species
- young - innately follow parents closely
- adaptive - if learn to recognize parent
- food
- protection
- innately predisposed to follow first moving object they see after birth.
- but apparently - young have an IRM (very rough) for parent
e.g. in geese - object needs to move and have min & max size
e.g. mallard - move, have rhythmic calls
can imprint on almost anything bue
if give young a choice
- prefer own kind
- over time - additional cues about followed object are added.
ii) Sexual Imprinting
- characteristics of sexual partner must be learned - very rough IRM
- many studies - show that IRM is much more developed in female
- males - have more learning to do
- if male finds raised with foster parent
e.g. Zebra & Bengalese
- prefer to mate with foster female
Immelman
took - zebrafinch - raised by society finch
- zebra finch remove @ 33 - 66 days
- housed individ. until sex. mat. - 4 mos
Hess - mallard ducklings
- kept in darkness for 1-35 hours after hatch
- for 1 hr - allowed to follow male mallard model
- with recorded calls
Major characteristics of object imprinting
- distinguish imprinting from other forms of learning
(1) innately controlled temporal motor
(2) takes place only during early sensitive phase
- may last few hrs - parental imprinting
Hess
but is different for different behaviours
e.g. sexual imprinting
- lasts longer (weeks or days)
e.g. in Zebra finch
- o-33 days
therefore sensitive phases for parental and sexual imprinting may overlap.
- sensitive phases
-may occur before birth
e.g. guillemot
- burrow nesting seabird
- acoustic comm. between embryo and parent
- adult respond to acoustic cues from embryo
- call back
therefore embryo learns calls of parent prior to hatch
- after hatch - recognize call of parent
(3) relatively irreversible
- result - long lasting hand
- cannot be determined later in life
e.g. - finches
- if kept with conspecific
- will eventually mate
- if given choice - prefer foster species
(4) time lag in sexual imprinting
- sexual imprinting - takes place before sexual maturity
therefore no immediate demonstration of object preference
- differs from parental
(2) Motoric imprinting
- performance of motor pattern
- perm. determined through early
e.g. birds
- song birds
- could learn only species specific song
how it works
- young male learns from father
- sensitive
- “memory template”
- matches song dev. against
- a kind of IRM for distinguishing its song
- after sensitive pd.
- hormones initiate attempt to match elements and then sequence of song
e.g. swamp & song sparrows
- overlap in range
- variation between birds - individual
NORMAL
INNATE - animals not exposed to song
- in various manipulations
- swamp sparrows
- exposed to song and swamp sparrow
syllables in different temporal pattern
- learn only swamp sp. syllables
therefore syllable is what is learned
Critical period in song learning - crowned
in general this works by
General
- functional aspects of imprinting
- why is it adaptive
(1) parental/filial recognition
(2) Km & species recognition
- recognize conspecific of opp. sex
- directing altruistic beh.
- inbreeding avoidance
Final types of imprinting
(1) Habitat imprinting (philopatry)
- migrating birds/fish learn char. of birthplace
e.g. Pac. salmon - odour
Two other behavioural systems associated with learning
(in an adaptive way)
(1) behavioural/cultural traditions
- tradition - transmission of acquired info.
(a) within group
(b) between generations by non-genetic means
e.g. (1) Japanese macaque
- potato washing - started by 1 female (1953)
remove sand
- habitat copied by her infants then other infants the whole troop
- now all do it
(2) 1930’s - blue tit - learned to open foil covers on milk bottles (operational)
- spread by across Europe
& to other spp. (24)
(3) Tool use
- sea otter
- chimps
- can come from operant condition
or
insight
passed by tradition
BIOLOGICAL RHYTHMS
- many behaviour patterns occur on a particular schedule
- daily
- seasonal
- yearly
biol. rhythms
- occur when activities and behaviour patterns can be directly related to regular environmental features
regulated by
biological clocks
- internal timing that involve
(a) physiological pacemaker
(b) external environmental synchronizers (ZEITGEBERS)
some terms
Properties of biol. rhythm
(1) oC - compensated - don’t with
(2) unaffected by metab. poisons or inhibitors
(3) occur with approximately same freq. as environmental features
(4) self sustaining
(5) can be (i.e. reset) by environmental cue
KINDS OF RHYTHMS
(1) Epicycles/Ultradian Rhythms
- short duration
e.g. big worm - Arenicola
feeds on flat
- leaves burrow to feed
6-8 mins
(2) Tidal Rhythms
- activity cycles of shore crabs
-match tides
(3) Lunar Rhythms
- 29.4 day cycle of moon
- related to tidal rhythms
e.g. Grunion - fish
- spawns on spring tides on beaches
- uses moon as cue
(4) Circadian
- about 24 hrs
- diurnal
- nocturnal
- crepuscular
- can shift seasonally
- governed by self sustaining pacemaker
(5) CircannUal
- pd. of about 1 yr.
- again - internal pacemaker
- self sustaining
e.g. diapause on insects
- pd. of dormancy in cold
Have said a lot about ‘Pacemakers’
- what is the evidence for them?
(1) Free-Running Rhythms
if put on animal under constrained conditions periodicity will shift
- illustrates a periodicity indep of 24 hrs clock
- re set by environmental cue
(2) Isolation Experiments
Hoffman (‘59) - lizard eggs - took at hatch & kept in different conditions
conditions were
(1) 9 h L : 9 h D - 18 hr day
(2) 12 L : 12 D - 24 hr day
(3) 18 L : 18 D - 36 hr day
- when tested all 3 groups showed a free running rhythm - 23.2 - 23.9 hrs
(3) Genetics
- mutations of genes that regulate clocks
e.g. hamster AA - 24.1 hrs
Aa - 22.0 hrs
aa - 20.0 hrs
- single locus mutant
(4) Translocation
-move animals from one location to another
e.g. in 50’s
bees - forage on daily rhythm
- coincide with flower opening
trained in Paris - flew to N.Y.
- in similar rooms etc.
- still on Paris time
- if do experiment outdoors
reset rhythm
Zeitgebers
- seem that endogenous rhythm
environmental cycle
therefore endogenous rhythm
- must be sy;nchronized with external stimuli
- entrainment
- entrainment cues - Zeitgebers
(time giver)
e.g. from previous expt with flying squirrels
- day light cycle - Zeitgeber
- entrained free running rhythm
- in flying squirrel
- also showed don’t need entire cycle
- 15 min light pd. at beginning of cycle - good enough
for most terrestrial organisms
- photoperiod is Zeitgeber
- why?
- very predictable
e.g. of solar eclipse
& works for several kinds of rhythms
- daily
- seasonal
- annual
- only major exception to photoperiod
- tidal rhythms
- most predictable cue for intertidal animals - tide not photoperiod
- important to animals
e.g. shore crabs - Warman & Naylor 95
- movement of tides
all - salinity
predictably - hydrostatic pressure
- showed 3 peaks of activity that corresponded to of variables tested
Where is this ‘Pacemaker’?
- are clock mechanisms hormonal or neural?
appear to be mainly neural
series of expt’s showed than decapitated roaches
arrhythmic
something in head is responsible
Page (‘82)
- took cockroach & removed optic lobes
- arrhythmic
- transplant optic lobes of 2nd roach - on different cycle
- after 4 - 8 weeks - restored rhythm
- recipient roach - takes on rhythm of donor
What about vertebrates?
- several implicate a region in hypothalamus
- suprachiasmatic nuclei (SCN)
- if destroy SCN’s loss of rhythm
but SCN’s not entire story
- if in monkeys
- lose rhythm
- maintain body temp. rhythm
- iof in rats
- maintain feeding rhythm
- suggestion is that ventromedial h hypothalamus (VMH) is involved
if destroy both SCN & VMH
- all rhythms lost
a third organ appears to be involved
- receives light stimuli (in birds, reptiles & amphibians)
- just under skull
- appears to work by secreting melatonin
- if remove from male hamsters and give injections of melatonin
- regression of gonads
- same effect as if had shortened daylight
- and finally if use labeled melatonin and look for area of greatest bindery SCN
Finally - adaptive value
- why have endogenous rhy;thms and not just rely on external cue.
(1) allows animal to anticipate dangerous conditions - on any time scale
(2) allows synchronicity of some functions
e.g. reproduction
- esp for external fertilizers
NEW PART OF COURSE
- start dealing with topics in animal behav.
- now have some info re basic concepts
- go on to talk about various topics in beh.
Migration
First General area - Habitat selection Territory
in book - ch. 5 & 10
First Topic - Habitat Selection
(1) MIGRATION
- Definition - act of moving from one habitat to another has been known for a long time
- e.g. prehistoric man - cave paintings
- ecol. necessity
- Bible & Aristotle
- modern study of migration - 1920’s
-migration may not always involve locomotion
- even though position
Functional Classification
Types
(A) Exploratory Migration
- takes animal outside limits of familiar area
- doesn’t preclude possess. of return?
- allows animal to assess suitability of new area
(e.g. dispersal from natal area)
(B) Removal migration
- migration from occupied habitat without returning / may involve different cues
(C) Return migration
- return to previously occupied habitat
- most widely recognized
Component of Migration - 8 of them
(a) Periodic timing
- initiation and termination periodic
- period can be daily, tidal, lunar
annual - 1 in 20 yrs eel
(b) Track pattern
(1) Loop migrations - e.g. plover, shearwater terns
(2) To & fro on ancestral routes (turtles, geese)
(3) Multiple population - specific routes
(c) Plane of movement
(1) horizontal
(2) vertical - moose, elk, plan kton
(d) Geographical direction
- most N.S. - why? - habitual
- albatross - E-W
(e) Direction ratio
- variation in scatter of movement
directions - about mean = for pop.
(f) Distance & Speed of movement
- very variable - few cm - aphids or leaf
- 1000’s of Km’s
- lot of variation
(g) Degree of return -
- all degrees between - one way removal and return migr =
(h) Migrant/Non-Migrant Ratios
(1) Intersexual variation
e.g. Ohio pop of song sparrows
- 50 % of males, 70% of females - migrate
(2) Ontogenetic Variation
- younger birds - higher probability of initiating removal migration
Next Lectures
deal with extremes of this
(1) long dist migr.
(2) passive dispersal
Best documented of all migrations
- very long distance - return migrations
- definition of long distance - purely arbitrary
- seasonal return > 1000 Km
How are migrations studies?
(a) direct obs
(b) radar -
(c) radio - tracking
(d) satellites
(e) mark receptive
(f) compare wintering & breeding ranges
Let’s look at this with long distance migrants
hypothesis - level of env. variables - perceived by organism
- compare to internal mech. & migrate or not.
Long distance migrants
- usually obligatory migration
Oblig. migr. - initiates migratory activity with ref. to habitat suitability & usually occurs at fixed time of ye;ar
- evolved in to fluct = in habit. suitability
Facultative
- response to decline in habitat
- fluct =
(1) Timing
- usually v. accurate
e.g. terns, shearwaters - arrive within 1 week every year
- salmon + 10 days
Exogenous
- photoperiod - most reliable & predictable
- argues 2 things
(1) physical mech. for measuring photoperiod
(2) on/off migratory mech
day length move south
- first demonstrate of role of photoperiod in coordinating migration & reprod cycles
Wm. Rowan
- Univ. of Alberta
Juncos (in winter)
Treatment Response
Control natural winter No gonad. gr.
day length No migr.
Exptl. Incr. photoperiod gonad gr.
(simulate spring) north migr.
even in winter
Once a migrant begin migration
- needs some way to tell where its going
- must
(1) determine general compass direction
(2) maintain direction during migration
3 General mechs that migrating animals can use
Type I: piloting - recognition of familiar landmarks
Type II: Orientation
- recognition and maintenance of a compass direction
- no ref. to landmarks
Type III: True navigation
- identification of “home” direction from any location
2 steps
(A) map sense - determine its location relative to some goal
(B) compass - maintain direction relative to position
How can tell orienting animal from truly navigating one
How?
- lots of cues are available
- unlikely that a single cue is used
- why? (1) if cue X is unavailable - need others
(2) if cue X may not be fine enough when get close to goal
- argument for
- hierarchy of redundant cues
- safeguard
Suggestions from recent bird studies
(1) hierarchy of cues
(2) in importance of cues during migration
(3) different ages use different cues
What kinds of cues are available
(A) Celestial Cues
(1) Sun-compass orientation
- restricted to diurnal migrants
- m values maintenance of compass dir. = by migr. at < rel. to sun
- must compensate (azimuth) corrector for movement of sun across sky
- animal must have daily clock
- can this be show
Questions
a) - do animals use these angular criteria?
b) Is there an internal clock?
Also must compensate for position of sun is more south
Example of sun compass
Can animals recognize sun compass
Bees -
- waggle dance
- L of linear
= L of food source rel. to sun
+ 10o & compensate for
(B) Stellar orientation
- maintenance of compass dir. = wrt. stars
- started with obs. that migratory songbirds - oriental S if exposed to clear sky in fall
& random if overcast
(C) Magnetic compass
- can follow geomagnetic lines
- many animals - sensitive to magnetic field of I as earth’s
X = 0.5
- intensity & inclination of line (dep <) vary with latitude
- can follow magnetic fields on migratory cue
- director of field
If take European
- in cage - oriented under local
with shift (with )
- get appropriate shift on orientation
Field test
Keeton - glued small magnets to pigeons
- .5 field
- eel 27-50 Km from ‘home’
- if sunny - all birds ret. h ome
- if cloudy - magnetic birds - scattered
- redundancy of cues
- sun compass - more than
A variation of theme
- small helmholtz
- att. to pigeon
- expt’l - & battery
- control - & no battery
- again - sunny skies - all returned
-cloudy - control OK
- expt’l - oriented at dictated by
(D) Moon Compass
- intertidal amphipods
- migrate up and down beach
- at night
- using moon as ref point
- compensate for
(E) Polarized Light
- bees use plane of polarized light to orient
(F) Topographic Landmarks
-
- more important in final stages of homing (pigeons)
(G) Sound
(H) Wind - gross der = l. cue
(I) Wave direction
- sea turtles
(J) Temperature gradients
- fish migrator
- shad - north migr. along east coast
- follow 15-18 oC th
(K) Olfactory
- salmon - final stages
“parent stream hypothesis”
(1) tributary - characteristic odour or set of odours
(2) Juveniles imprint on natal stream & every stream on way to ocean
(3) memorize odours in sequence
(4) recall and respond to odours in reversed sequence
That’s how migration may be governed
Why?
Evolutionary considerations
- probable evolved in diff. group
What sel pressures are in common
Change in quality of habitat
(1) climatic
(2) in food abundance, nest sites, etc.
(3) increased density ( )
- le
Talk in terms of costs and benefits
costs (1) energetic
(2) prediction - travel in group
(3) metabolic investment in navig. systems
(4) genetic
benefits (1) genetic X between
(2) reduced competition
(3) better food sources
Migration
Passive dispersal
- other end of spectrum from long distance migration animals - entirely dependent on environment
- going to concentrate on marine inverts.
(1) How does it happen?
- most work done with corals but same principles apply to any drifting animal
- mass spawn on GDR
- lots of scleractinian and octocorals
- spawn at same time
- drifting of eggs and sperm can be seen from boats/planes
- effect is to wash offspring away from reef.
First Pt. - seems to happen at surface
Can largely ignore subsurface current
Question 1
do corals spawn in such a way that is into a particular set of env. conditions
- wind - SE
- current - NW Helix
- tides NE SW Reef
- same diurnal
- result of this
- put these data into a model
- very low flushing rates
The looked at patches of slicks
- residence time around natal reef - very high
Then looked at settlement probability
- highest rear natal reef
< 20% > 5 Km away
notion of long term dispersal not accurate at least for some species
One well known study of long term dispersal sch
- sample (plankton tow)
- across N Atlantic
- for this study looked at mollusc larvae
had to (1) originate in shallow water
(2) found in open ocean
distrib. in N. Atlantic
general circulation
- general finding
- larvae were in green ocean & on wrong side
So far - not much behaviour
except for spawning times
- swimming of larvae - little no eff
- too slow
But so far have only dealt with 1/2 the
what about stopping this migration
already said that don’t know what stops bird migration
What induces settlement and metamorphosis in marine larvae - Mollusc
Stage (1) Coming out of H2O column
looked at phototaxis
result
Then looked at vertical
- light from top
finally swimming pattern
what have is a clear picture of in larvae as age
- young - photo positive
- old - photo negative
will settle
That gets animal going in right direction
- what determines where precisely it will settle
again - data from molluscs
gastropod Phestilla
- settles on coral Porites
Hypoth - something given off by coral
- “inducers”
- kept coral fingers in distilled water and test in various concentrations
also age dependent
specificity of response
have a chemically induced settlement that takes eff. after light-induced setting
Have looked at 2 modes of dispersal (migration)
- long dist. - goal directed - map/compass
- shorter (?) dist.
- at whim of env.
- very probable
- cues for ending it
2nd TOPIC IN “USE OF SPACE”
TERRITORY
First - need to separate a couple of concepts
- home range - from territory
(1) HOME RANGE
- area where animal spends its life (if not dispersing)
- not defended
- established by mapping position & & connecting outermost points
- not equally used by animal
- some parts fulfill habitat require - better
- core areas - internal use
so instead of mapping
- can overlap with h.r.’s of other animals
(2) TERRITORY
- an area occupied by an animal or group of animals from are excluded - by aggression or threat
Territoriality
- social system
- consequence of territory
- dispersion of individuals
- indicator
- animals spaced more evenly through habitat than exp. by chance
Attributes of territorial behaviour
(1) several activities to a defended area
(2) advertise presence within defended area
(3) maintain exclusive possession of all parts of area
Classification of Territories
- based on different
(1) FUNCTIONAL - access to resource defended
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