Evolution and Behaviour Fundamentals

Question 1

How does natural selection work by evolution?

Answer 1

1) Phenotypic variation in a population - assisted by a mutation
2) Variance heritable by genetics
3) Survival/reproduction success influenced by phenotypes
4) Individuals compete to survive/reproduce
5) Successful individuals perpetuate genes for good phenotypes
6) Phenotypes with high fitness are selected to continue

Question 2

Explain the role of sense organs in creating behaviour

Answer 2

Gathers information about the physical, chemical and biological environment.
Hierarchical complexity - simple light or dark receptor organs to full functioning eyes.

Question 3

Explain the role of nerves in creating behaviour

Answer 3

Action potential generated from sensory organ passes down neurone and generates the release of neurotransmitters into the next neurone junction.
Concentrated ganglia/brains allow the storage of information.

Question 4

Explain the role of muscles in creating behaviour

Answer 4

Simple structures that form complex organisms. Motors allow physical movement and behaviour.

Question 5

Describe simple behaviours

Answer 5

Reflexes, stereotypical, automatic, simple stimulus and neural pathway, form is constant, consistent and momentary. E.g knee jerk

Question 6

Describe complex behaviours

Answer 6

Fixed action patterns, innate, stereotypical, complex stimulus and neural pathway, more variation in context and habituation. Fixed action patterns can link up to form very complex behaviours. E.g moths jamming the echolocation of bats to avoid predation.

Question 7

What are Tinbergen’s four questions?

Answer 7

1) Causation
2) Development
3) Evolution
4) Function

Question 8

Why do birds sing complex songs?

Answer 8

Causation - Day length triggers hormonal changes and air flowing through their syrinx makes membranes vibrate. Their genes code for an instinctive response to a change in hormone concentration.

Development - They have learnt the song from their parents/conspecifics.

Evolution - Their ancestors had simple songs that developed over time.

Function - Complex songs attract mates and drive competitors away.

Question 9

What are proximate and ultimate questions?

Answer 9

Proximate - Based on immediate cause and mechanism.

Ultimate - Based on survival/reproduction value in nature, evolutionary significance.