Transcript Connectivity over ecological and evolutionary time in coral

Connectivity over ecological and
evolutionary time in coral reef fishes
Serge PLANES
Connectivity over ecological and evolutionary time
Serge Planes ([email protected])
Connectivity, why is concentrating so much effort…
• Represents the scale at which populations
respond to the environment.
• Represents the scale at which species adapt to the
environment.
• Scales of management can be adjusted to dispersal
distances to achieve different management goals.
For example, the appropriate size and/or spacing of
marine reserves as:
• Harvest refugia
• Conservation sanctuaries
Connectivity over ecological and evolutionary time
Serge Planes ([email protected])
Connectivity and conservation…
=> Different processes, different mechanisms, different interpretations
Different approaches (genetic)
Connectivity over ecological and evolutionary time
Serge Planes ([email protected])
Genetic approach… (genetic models)
Species level
=> phylogeny, phylogeography
=> mutation from common ancestor
Metapopulation level
=> gene flow estimates
=> Allelic frequencies variation
Population level
=> self recruitment
=> relatedness estimates
Connectivity over ecological and evolutionary time
Serge Planes ([email protected])
Speciation and dispersal of species
• Several evidences of geographix isolation
 Temporal concordance among clade genesis
 Temporal concordance in relation with sea-level change
 Evidence of allopatry in younger clades
• No sympatry found before 4 My of divergence
• Absence of geographic concordance among clades
=> Overall modern distribution of species is not related to its age
whatever their dispersal capabilities
Connectivity over ecological and evolutionary time
Serge Planes ([email protected])
Population genetic to understand connectivity…
=> No general trend among the several species surveyed
GBR, Polynesia : different out comes
=> Assumption of equilibrium in most computations and
consider all species on a same evolutionary stage
=> genetic structure cannot be directely translated into
biological and ecological outcomes
Connectivity over ecological and evolutionary time
Serge Planes ([email protected])
Paternity approach
• Numerous variable markers
Need to characterise each individual (microsatellite)
Example:
A species case with 10 loci (µsat)
(independant, equilibrium, equally frequent)
=> the number of potential allele combination is 10(2x10)
Allele 1 Allele 2 Allele 3 Allele 4 Allele 5 Allele 6 Allele7
10 10 10 10 10 10 10 10 10 10 10 10 10 10
….
=> the probability to found 2 similar genotypes is 1/ 10(2x10)
=> Far from most population size at regional area
• Collect tissues samples of potential adults
• Collect of new recruits
The Kimbe bay - Amphiprion percula case study
Kimbe Bay case study
Adult sampling
Kimbe Bay case study
2004
(Total new recruits)
2
G
(10)
D
(21)
2
C
(10)
2
2
3
3
B
1 (20)
4
E
9 (37)
3
2
F
(1)
A
(31)
15
6
Overall selft-recruits
66 out of 130 (51%)
Lagoon A: 15 (48%)
Lagoon B: 1
Lagoon C: 0
Lagoon D: 1
Lagoon E: 9 (24%)
Lagoon G: 1
Main Flux: G-C-B-A
Kimbe case study
6%
71
34
Kapepa
Turae
2
4
Restoff 3
10%
39
11
1
Schuman
Kimbe
2 3%
59
Wulai