Behavioural Biology 21-22
Lec 1 - Chapter 1, 2, 3 Riedstra
Chapter 1. The Science of Animal Behaviour
- What is behaviour?
- How to measure behaviour?
- Philosophy of Behaviour
- Perspectives in a historical context (read yourself)
What is an animal?
An animal is an organism:
- Multicellular eukaryotic - all cells have a nucleus (mammalian red bloodcells do not!)
- Dependent on organic materials
- Breathe, move, nervous system, sensory systems
- Have a blastula (hollow sphere of cells) during early embryonic development
What is behaviour?
Animal behaviour is any internally coordinated, externally visible pattern of activity that
responds to changing internal or external conditions.
Internal: Information processing (hormones, sensory info, neurotransmitters)
External: Observable and measurable
So, behaviour is anything an animal does (including sleeping)
Different definitions of behaviour:
- Ultimate expression of the complexity of an animal (philosophical)
- Integrates physiological and morphological parameters in interaction with the
environment
- Individual behaviours dictate phenomena at higher levels (groups/populations)
Quantifiable: behavioural biologist quantify behaviour
How to measure behaviour?
- Ethogram: formal description of an animal’s behaviour (Time budget)
Stereotypes (in ethogram)
- No obvious goal or function !?
- What is ‘not obvious’
- Always be critical (elephants; stereotypical behaviour is to reduce stress/happy state)
Measuring behaviour → observation Practical (ch.11; habitat selection, territoriality, and
aggression)
,Philosophy of Behaviour (Niko Tinbergen)
- Proximate 1) development
(How?) 2) mechanism
- Ultimate 3) function
4) evolution
Top-down vs bottom-up
Perspectives in a historical context
Avoid anthropomorphism
Avoid Anecdotal evidence
Correlational and experimental evidence (cause & consequence)
Systematic ((double) blind) observations
Nature vs Laboratory conditions
Evolutionary context
Interdisciplinary approaches
Chapter 2 - Methods for studying animal behaviour
,So: Question → Preliminary observations → Formulate hypothesis → formulate specific
predictions → determine the variables needed → Choose method to measure variables →
collect (enough) data → analyze data properly → question!
Preliminary observations → Knowledge (lack of), curiosity, observations, Q: from somebody
else, statement → Question
Formulate specific predictions, determine the variables needed, choose method to measure
variables → experimental design/method
Example:
Research questions
- Question → hypothesis → testable predictions → quantifying behaviour → statistics →
report
- H0: A=B > statistics
- H1: A is not B > statistics
-
Methods:
- Observational method → hypothesis
Observational method: causality unclear, used to test hypotheses and describe behavioural
patterns
Hypothesis: Ecological & evolutionary context (an explanation based on a coherent set of ‘facts’
and assumptions
- Experimental method → report
, Experimental method: Direction of causality is clear, Ethics: Refinement, Replacement,
Reduction
Report: publication
- Comparative method: mainly for ultimate explanations, understand evolution of
behaviours comparing closely related species, Ancestral or derived traits
→ Understanding evolution of traits! A scientific field never stands on its own (other fields)
- Modelling: Yields testable predictions, Meta-analyses
Where to study animal behaviour
- In the wild
- In semi-natural conditions
- In the lab
Pro’s and cons
Standardisation vs Real life
Domesticated species vs wild caught species
Ch 3 - Evolution and the Study of Animal Behaviour
‘Nothing in biology makes sense except in the light of evolution.’ - Theodosius Dobzhansky
1973
Evolution: change in the (alleles) inherited characteristics of biological populations over
successive generations
3 conditions for evolutions
1) Heredity (DNA/RNA, genes)
2) Variability (mutations, recombination, gene flow)
3) Selection (natural/sexual selection, drift)
What is an animal?