Effects of habitat fragmentation on parental correlations in the seed rain of a bird-dispersed species
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Seed dispersal plays a crucial role in natural forest regeneration. Changes in the seed rain due to anthropogenic habitat alteration can influence seedling recruitment patterns and affect the evolutionary dynamics of populations. Using a combined endocarp-embryo microsatellite assay of naturally dispersed seeds, we concomitantly quantify the contribution of contemporary pollen and seed dispersal to the genetic structure of the seed rain of the shrub species Pistacia lentiscus L. The study was conducted in two consecutive seasons at four forest fragments embedded in contrasting (connected vs. isolated) landscapes. Interseasonal variation in the parental genetic structure of the seed rain was assessed through analysis of molecular variance, and paternal and maternal correlations and effective parental numbers were computed for different fragments and microhabitats (within fragments) using genetic kinship analysis. Temporal variation in the genetic structure of the dispersed seeds was higher for maternal gametes, reflecting a more temporally variable contribution of individual mother plants to the seed rain, as a potential consequence of masting and/or natural heterogeneity. Higher effective numbers of fathers than mothers were consistently observed in all studied forest fragments and microhabitats, the difference being more pronounced for connected than for isolated fragments. The effective number of mothers, directly influenced by disperser birds’ behavior, was apparently insensitive to fragmentation. Despite potentially high mobility of pollen by wind and seeds by birds, habitat fragmentation could influence the parental structure of dispersed seeds, with potential consequences for the genetic structure of the adult generation.
KeywordsGene flow Pistacia lentiscus Pollen and seed dispersal Kinship Parental structure analysis
The authors thank to the local landowners for permission to work at the study sites, S. Nora for field and laboratory assistance, and E. Villalobo, three anonymous reviewers, and the editor for helpful comments on the manuscript. This study was supported by a grant from the Spanish Ministry of Economy and Competitiveness (CGL2011-23721). JJRA was partly supported by CGL2015-64164-R project from the Spanish Ministry of Economy and Competitiveness. CPF is supported by a predoctoral fellowship from Ministry of Economy and Competitiveness (BES-2012-055103).
Data Archiving Statement
Microsatellite data is already uploaded to the dryad database with the accession number doi: 10.5061/dryad.45t51
- Albaladejo RG, Sebastiani F, Aparicio A, Buinamici A, González-Martínez GC, Vendramin GG (2008) Development and characterization of eight polymorphic microsatellite loci from Pistacia lentiscus L. (Anacardiaceae). Mol Ecol Resour 8:904–906. doi: 10.1111/j.1755-0998.2008.02110.x CrossRefPubMedGoogle Scholar
- Aparicio A (2008) Descriptive analysis of the ‘relictual’ Mediterranean landscape in the Guadalquivir River valley (southern Spain): a baseline for scientific research and the development of conservation action plans. Biodivers Conserv 17:2219–2232. doi: 10.1007/s10531-007-9295-y CrossRefGoogle Scholar
- de Bello F, Lavorel S, Díaz S, Harrington R, Cornelissen JHC, Bardgett RD, Berg MP, Cipriotti P, Feld CK, Hering D, Martins da Silva P, Potts SG, Sandin L, Sousa JP, Storkey J, Wardle DA, Harrison PA (2010) Towards an assessment of multiple ecosystem processes and services via functional traits. Biodivers Conserv 19:2873–2893. doi: 10.1007/s10531-010-9850-9 CrossRefGoogle Scholar
- Grivet D, Robledo-Arnuncio JJ, Smouse PE, Sork VL (2009) Relative contribution of contemporary pollen and seed dispersal to the effective parental size of seedling population of California valley oak (Quercus lobata, Née). Mol Ecol 18:3967–3979. doi: 10.1111/j.1365-294X.2009.04326.x CrossRefPubMedGoogle Scholar
- Iwaizumi MG, TakahashI M, Isoda K, AusterlItz F (2013) Consecutive five-year analysis of paternal and maternal gene flow and contributions of gametic heterogeneities to overall genetic composition of dispersed seeds of Pinus densiflora (Pinaceae). Am J Bot 100:1896–1904. doi: 10.3732/ajb.1200563 CrossRefPubMedGoogle Scholar
- Jordano P (1988) Polinizacion y variabilidad de la produccion de semillas en Pistacia lentiscus L. Anales Jard Bot Madrid 45:2123–2231Google Scholar
- Jordano P (2007) Frugivores, seeds and genes: analysing the key elements of seed shadows. In Dennis AJ, Green RJ, Schupp EW (eds.) Seed Dispersal: Theory and its Application in a Chagings World 229–251.CABIGoogle Scholar
- Karubian J, Durães R (2009) Effects of seed disperser social behavior on patterns of seed movement and deposition. Oecol Bras 13:45–57Google Scholar
- Schupp EW, Milleron T, Russo SE (2002) Dissemination limitation and the origin and maintenance of species-rich tropical forest. In: Levey DJ, Silva WR, Galetti M (eds) Seed dispersal and frugivory: ecology, evolution and conservation. CAB International, Wallingford, pp 19–23Google Scholar