Kahilainen et al., 2014 - conservation implications of species-genetic diversity correlations Flashcards Preview

APS271 Conservation Principles > Kahilainen et al., 2014 - conservation implications of species-genetic diversity correlations > Flashcards

Flashcards in Kahilainen et al., 2014 - conservation implications of species-genetic diversity correlations Deck (8)
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1

Why is intrapopulation genetic diversity important for the long-term persistence of populations?

- genetically determined phenotypic variation equated to a populations adaptive potential

- neutral genetic variation in populations reflect genetic drift & inbreeding which both reduce population viability

- reduced genetic diversity is related to extinction risk

- the ultimate goal of conservation actions is to ensure the long-term persistence of species,
- the conservation of intrapopulation genetic diversity should be of high priority

2

What is SGDC/what are studies on it useful for?

- species-genetic diversity correlations

- info on whether conservation of intrapopulation genetic diversity can conflict w conservation of species diversity / vice versa

- increases in area/connectivity are associated with positive SGDCs and persistence of species diversity

3

What are alpha SGDC (α-SGDC)

- relationship between species diversity in a local community & intrapopulation genetic diversity within the species

- observed both negative and positive in natural systems
- sign of the α-SGDC directly indicates whether there is a conflict between the conservation of the two levels of biodiversity
- postive α- SGDC = actions to conserve species diversity in a community likely to conserve intrapopulation genetic diversity too
- negative α-SGDC = opposite

- driven by stochastic processes, dispersal, and selection

- stronger on islands/island like localities

4

What is beta SGDC (β-SGDC)?

- differentiation between SDGCs at different localities

5

What drives genetic diversity within populations?

- genetic diversity within populations
(e.g. haplotype diversity, allelic richness, heterozygosity, or quantitative genetic variation)
- influenced by population size, gene flow, and selection
- above can be driven by same environmental characteristics that drive species diversity

6

What is the relationship of SGDCs with area?

- when community size positively correlates with area, area can drive positive α-SGDC
e.g. via stochastic processes, sampling effect

- # observed species increases with area
- extinction rate declines with area due to reduced demographic stochasticity

- average population size increases with increasing area
- more genetic diversity sampled from the regional gene pool
- reduced
intensity of genetic drift
- larger populations tend to be more genetically diverse

- expected to drive positive β-SGDCs

7

What is the relationship of SGDCs with connectivity?

- connectivity influences dispersal between localities
- well connected localities more likely to receive immigrants from more species than unconnected ones
- also receive more alleles

- connectivity expected to drive positive α-SGDCs

- connectivity is expected to influence degree of community & genetic differentiation in parallel
- positive β-SGDC

8

What is the relationship of SGDCs with environmental heterogeneity?

- spatial/temporal/spatio-temporal

- increasing environmental heterogeneity = suitable conditions for more species to persist in a locality, less chance of competitive exclusion
- more species in environmentally heterogeneous areas

- can cause disruptive selection
- allow for varying genotypes w/i a population

- BUT can end up selecting for generalists potentially reducing SGDCs (number of species & genetic diversity)

- may also support smaller populations of more species
- increased rare habitats, but smaller habitats
- higher species diversity but lower genetic diversity?