Transcript Diapositive 1

Banbury 28-31 october 2007
Can we extend intraspecific population genetics
to community population genetics ?
Michel Veuille
Ecole Pratique des Hautes Etudes
Unité de recherche 5202 CNRS-MNHN
Paris
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
We will admit that:
(1) research on COI as an evolutionary genetics system has been investigated intensively
for the last 25 years. We know its properties as a population marker,
(2) 650 bp of COI sequence (a single sequencing run) convey very little information, though
enough information to resolve 95% of species identification,
(3) It conveys even less information on intraspecific female variation, but can be used in ~
25% species,
(4) The sample size may be small in highly variable species
(5) We are not interested in the barcode but in whatever information that is relevant to
population biology.
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
Over the last 30 years, our
view population stablity
changed
The repertoire of population
biology models, relies on
equilibrium or steady state
conditions.
e.g.
Species/area distribution
Colonization-extinction model
Hubell’s neutral model
Island model
Yule’s model
Coalescent model
Empiricists usually try to falsify
these models to understand
the history of species
After Wilson and Bosset 1971
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
However, many changes in the history and distribution of populations are due to strong
external factors, acting on groups of species (communities)
We know that the last big climatic change occured only ~ 104 years ago, with
consequences on:
- species range in boreal areas
- forests and arid zones distribution in tropical areas
- sea level and shoreline patterns
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
For instance, Hewitt (2000) was able to synthesize the distribution pattern of twelve
European species into three routes of northward extension.
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
Species A Species B
If the availability of different kinds of environment change
over time, then variation patterns will change accordingly
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
Species A Species B
If the availability of different kinds of environment change
over time, then variation patterns will change accordingly
Our ability to explore remote events also changed over the
last 30 years
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
Present
An example from
the literature :
mtDNA haplotypes
in coral reef fishes
120 m
- 18 ky
Michel Veuille
After Fauvelot et al. 2003
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
Proposal: study population differentiation simultaneously in several species
From the barcode library, choose some indicator species to explore the history of ecosystems
It might be appropriate to adjust the sample size in these species
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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Banbury 28-31 october 2007
Resolution power of methods : how much effort should we put in every species ?
A cautionary tale: timing of Drosophila melanogaster expansion from Africa to Europe
• 1995 Bénassi and Veuille (restriction polymorphism in n = 200)
Population divergence 10.000 years ago
• 2004 Baudry, Viginier and Veuille (sequence polymorphism in 4 genes in n = 153)
Bottleneck 6.400 years ago
• 2005 Ometto Glinka De Lorenzo Stephan (sequence polymorphism in 260 genes in n = 24)
Expansion 60.000 years ago in eastern Africa
followed by a bottleneck 16.000 years ago in Europe
Michel Veuille
Ecole Pratique des Hautes Etudes - Paris
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