Outline for Lecture 3 Levels of Analysis
1. Different types of questions: proximate causation (what goes on within a life span) vs.
ultimate causation (why would any organism have the proximate mechanisms - why are they
present in any species)
o #1 Why does the door open?
Does it open to let people in or does it open because of motion sensors?
This is an incorrect way of asking this question because the answer is -
both is correct
One is how it works and the other answers why (the function and the
mechanism) - to say it's one or the other is a false dichotomy
o #2 Why do we eat?
Refer to the example above - same idea
- We are following adaptive evolution
- Motivations will evolve which is statistically associated with reproductive success
2. Tinbergen’s Four Questions (a.k.a. Levels of Analysis):
Are divided into two cases - proximate and ultimate causes:
- Proximate Causes
Mechanisms: what physiological, cognitive (etc.) processes trigger behaviour at time T?
Developmental Processes: how does that mechanism develop within individual lifetime?
o Whatever that mechanism is - how did it develop (aka ontogeny)
o Development can change and alter the mechanism/the brain
- Ultimate Causes
Function: what are the effects of that behaviour on fitness? Why would it exist at all?
o Why would any organism do that behaviour
o Social success and reproductive success
Phylogeny: what are the evolutionary origins of the behaviour? What did it evolve from?
o Evolutionary history/evolutionary past
o When did this trait evolve and why did it evolve
- Our brain is continuously changing - that is learning, if your brain doesn’t change it
means you are not learning.
These levels of analysis are complementary, not mutually exclusive. All four are necessary.
The only conflict is among answers at the same level, e.g. two alleged developmental processes
3. Example #3: breast-feeding
- Mechanisms - at time T - what is going on in her brain that causes this behaviour
(hormones, presence of milk, infant cry being distress and giving the infant what they
- Developmental response - behaviour becomes more desirable to hormone development,
whether or not they learn to breast feed - all reasons to cause the behaviour within the
- Function - parental investment - way of feeding the infant so that they grow and thrive