Foundation species such as redwoods, seagrasses and corals are often long-lived and clonal. Genets may consist of hundreds of members (ramets) and originated hundreds to thousands of years ago. As climate change and other stressors exert selection pressure on species, the demography of populations changes. Yet, because size does not indicate age in clonal organisms, demographic models are missing data necessary to predict the resilience of many foundation species. Here, we correlate somatic mutations with genet age of corals and provide the first, preliminary estimates of genet age in a colonial animal. We observed somatic mutations at five microsatellite loci in rangewide samples of the endangered coral, Acropora palmata (n = 3352). Colonies harboured 342 unique mutations in 147 genets. Genet age ranged from 30 to 838 years assuming a mutation rate of 1.195−04 per locus per year based on colony growth rates and 236 to 6500 years assuming a mutation rate of 1.542−05 per locus per year based on sea level changes to habitat availability. Long-lived A. palmata genets imply a large capacity to tolerate past environmental change, and yet recent mass mortality events in A. palmata suggest that capacity is now being frequently exceeded.
DuranteEtAl_Apalmta_Genotypes_n=3352
Genotypes for the coral, Acropora palmata from five microsatellite loci. A. palmata is a diploid species, however, somatic mutations in the form of third and fourth alleles per locus are occasionally detected. Samples are in rows (n = 3352), genotypes are in columns.
Table Headers
Species: Acropora palmata
Region: Caribbean and North-west Atlantic.
Database ID: A unique name given to each coral sample.
Locus 166, alleles 1-4: Locus 166 is a microsatellite locus. Alleles are given in basepairs.
Locus 181, alleles 1-3: Locus 181 is a microsatellite locus. Alleles are given in basepairs.
Locus 182, alleles 1-4: Locus 182 is a microsatellite locus. Alleles are given in basepairs.
Locus 192, alleles 1-4: Locus 192 is a microsatellite locus. Alleles are given in basepairs.
Locus 207, alleles 1-3: Locus 207 is a microsatellite locus. Alleles are given in basepairs.
Genet ID: All samples that share all ancestral alleles at five microsatellite loci were assigned the same genet ID. See methods for how ancestral alleles were determined.
Mutant ID: A Unique ID given to each unique multilocus genotype. This multilocus genotype includes all alleles (diploid ancestral and additional mutations).
DRYAD_Genotypes for Clonal Age paper-V2.xlsx
DuranteEtAl_AcroporaPalmata_UniqueMutationsTable
Table shows the somatic mutations that occurred at 5 microsatellite loci in Acropora palmata collected throughout the Caribbean. Given are the sampling region, the reef, the Baumslab sample Database ID (unique for each sample), the microsatellite locus that had a mutated allele (166, 181, 182, 192,207), the two ancestral alleles of the genet, any additional alleles detected and a designation (Origin of Allele 3, Origin of Allele 4) of how those additional alleles arose (i.e from ancestral Allele 1 or Allele 2). Sometimes, one ancestral allele mutated twice giving rise to Alleles 3 and 4. The mutational change (in bp) from the ancestral alleles to the new allele is given. Genets had from 2 to 94 samples (sample count for genet). Genets are identified by their Genet ID. Sometimes, ancestral alleles were no longer detected (full mutations). CBD = cannot be determined.
DRYAD_unique mutations table.xlsx