Lecture 17: Genes and Behaviour

Question 1

What are genes?

Answer 1

A lengths of DNA that encodes the information for constructing a particular protein

Question 2

What are genotypes?

Answer 2

The entire set of genes an individual possesses (passed on by parents)

Question 3

What are phenotypes?

Answer 3

The observable characteristic of an individual, influence by genes and environment

Question 4

What are allele’s?

Answer 4

A version of a given gene
- Individuals have one or two alleles of a gene, but multiple alleles can exist in the population

Question 5

What did Sokolowski (2001) say are the challenges of behavioural genetic research?

Answer 5

• difficulty in defining and quantifying behaviour
• environmental influences on behaviour
• within- and between-individual variation in behaviour
• involvement of many genes
• different genes function in different tissues at different times during the development of an organism

Question 6

What is the burrow structure of deer mouse?

Answer 6

• lives in grassy/forest habitat
• builds burrows with short entrance tunnel and no escape tunnel

Question 7

What is the burrow structure of oldfield mouse?

Answer 7

• lives in open habitats (beaches, fields)
• builds burrows with long entrance tunnel and escape tunnel

Question 8

Explain Weber et al (2013) study?

Answer 8

• Captive-reared mice placed in sand-filled arena for first time builds species-typical burrow
• F1 offspring of maniculatus × polionotus hybrid
  
  • 100% escape tunnels
• Backcrossed F1 × maniculatus
  
  • 50% escape tunnels

→ Single, dominant locus controls building of escape tunnel

Question 9

How do genes contribute to behaviour?

Answer 9

Gene expression acts at different phenotypic levels

Expression of a gene can influence:

• expression of other genes
• activity of the cell, other tissues and organs
• developmental processes
• activity of brain, muscles, messenger systems → expression of behaviour

Environmental influences act on gene expression and/or on phenotype

Question 10

What is total phenotypic variance in a trait?

Answer 10

Is based on addictive effects of genetic variance and environmental variance

Question 11

Total phenotypic variance =

Answer 11

Genetic variance + environmental variance

Question 12

Trait heritability =

Answer 12

Genetic variance / environmental variance