Lecture 28 Flashcards Preview

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Flashcards in Lecture 28 Deck (10)
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1
Q

Ecological genetics:

A
  • Understanding genes in natural environments
  • Adaptation and how organisms undergo adaption
  • Survival and reproduction
  • ## Evolutionary processes in nature and the extent to which species are able to adapt
2
Q

Quantitative genetic diversity:

A
  • Traits associated with many genes

eg) size is measured on a quantitative scale and is associated with multiple genes and is under selection

3
Q

Allozyme variation in butterflies and PGI:

A
  • PGI is an allozyme with different forms across the population
  • The gene is protein coding
  • Heterozygotes are more active at cooler morning temperatures
  • The quantitative behaviour is flight behaviour
    This gene has a big effect on flight behaviour.
4
Q

Early flight provides a reproductive fitness advantage

A
  • Functional studies show that PGI heterozygotes fly better in the cold
  • 3/4 heterozygotes perform better, in the field and in the lab
  • This will maintain variation in the population
5
Q

PGI variation is ubiquitous in insects flight ability:

A
  • This allows extension from gene to trait

- Balancing selection is maintained here

6
Q

Chromosomal rearrangement:

A
  • Inversions
  • polymorphisms for chromosomal rearrangements such as inversions exist
  • Inversions can be studied
7
Q

There are many example of genetic polymorphisms under selection:

A
  • Several allozymes
  • Chromosomal rearrangements
  • Insertions/deltions
  • SNPs
8
Q

Multiple polymorphism scans allow us to determine how adaptable a particular genome is:

A
  • Carried out across time or (usually) across space
  • Ideally this will be replicated across time or space to determine a difference
  • Fst analyses can be used to identify outliers and loci with very large Fsts are looked for
9
Q

Arabis alpina is a plant studied in relation to elevation:

A
  • Fst was studied and two peaks were found
  • This means there are two genomic sequences associated with elevation
  • What genes are these? How do they effect the polymorphism?
10
Q

Genome Wide scans are

A
  • Markers are available across entire genomes
  • They may involve re-sequencing or markers such as RADs
  • It is important to separate population processes, such as admixture
  • Functional analyses of identified polymorphisms are needed
  • This identification does not indicate how important a polymorphism is for a trait without additional functional analysis
  • How many other genes are involved and what fraction of the variation in the trait is determined by that particular gene?