PT  - JOURNAL ARTICLE
AU  - Mikhail V. Matz
AU  - Eric A. Treml
AU  - Galina V. Aglyamova
AU  - Madeleine J. H. van Oppen
AU  - Line K. Bay
TI  - Adaptive pathways of coral populations on the Great Barrier Reef
AID  - 10.1101/114173
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 114173
4099  - http://biorxiv.org/content/early/2017/05/23/114173.short
4100  - http://biorxiv.org/content/early/2017/05/23/114173.full
AB  - There is an urgent need to understand factors influencing the potential of reef-building corals to adapt to future thermal regimes. Here we infer demographic parameters in five populations of the common coral Acropora millepora and use them to model future adaptation of the species on the Great Barrier Reef (GBR). Genetic analysis of samples collected 2002-2009 revealed that the loss of about half the coral cover in the preceding three decades did not yet result in detectable loss of genetic diversity or changes in gene flow. Both genetic and biophysical models indicated the prevalence of southward migration along the GBR, which would facilitate the spread of heat-tolerant alleles to higher latitudes as climate warms. Using a newly developed metapopulation adaptation model we find that standing genetic variation could be sufficient to fuel rapid adaptation of A. millepora to warming for the next 100-200 years. However, thermal anomalies such as ENSO cycles will drive increasingly severe coral mortality episodes. New mutations are unlikely to sustain genetic variation in the face of such strong selection, and so after the initial rapid adaptive response coral populations will go extinct, beginning with warmer locations.