Download Development of Behaviour

Development of
Behaviour
Psychology 3106
Introduction
So far we have looked at Evolution and
Genetics

Go together in the modern Synthetic Theory
of Evolution
Evolution acts on the phenotype
Genetics (interacting with the
environment) create the phenotype
Development links genotype to phenotype
Introduction
Development is the unfolding of the
phenotype in a particular environment
Not the Nature v Nurture ‘controversy’
again!
That great Hebb quote
Interaction principle is the key
You cannot have genes without an
environment, and vice versa, so get over
it!
Important Ideas in Development
Canalization or Developmental
Homeostasis

The capacity for structures to develop even if
conditions are suboptimal
Ghysen (1978)


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Misdirected nerve cell in Drosophila
Ganglion grew the wrong way
Eventually projected to the right place!
More Developmental Issues
Well, that’s all very
interesting Dr.
Brainiac, but what
about behaviour?

Fine question….
Social Behaviour of
Rhesus Monkeys
(Harlow and Harlow)
The Evil Harlow
Those poor monkeys……
But, the nice thing was
that when a normal
monkey interacted with
the messed up one, it
could, in essence, give
the poor guy therapy
Even surrogate mothers
worked!
Even under such nasty
conditions, normal
development was
possible (with a little
environmental tweaking)
More Key Issues
Sensitive Periods
Animal’s nervous system needs certain
input at a certain time or development will
stop

Human vision and me, for example
Development may not exactly stop, but it
may turn out to be quite a bit different.
The lecture continues to develop
Experience Expectant vs. Experience
Dependent Information Storage

Experience expectant
Like information needed in a sensitive period
Generallhy needed for all species members

Experience Dependent
Individual level
Makes individuals different
Imprinting
Imprinting is another great
example


Pretty much the first thing a bird
sees becomes its ‘mother’
‘Not Learning’
Clayton has found that
Amount of NMDA receptors in
IMHV increase by 57% after
imprinting in chicks!
Song Learning
In songbirds it In pretty
much works like this:


Males sing
Females don’t
Marler thought that there
was a ‘template’ in the
bird’s brain.
Needed to hear himself
sing around 150-200 d
post hatch or he’d never
sing
Thought they could only
acquire their own song
Listen to the pretty birdies….
Not quite a template eh Pete?
Hormonal effects are huge in
development
Conclusions About Development
Gene / Environment interaction
Development is sort of the unfolding of the
phenotype by the genotype (with
environmental interaction
Critical periods usually aren’t