Abstract Detail


Benítez, Carmen Benítez [1], Jiménez-Mejías, Pedro [2], Calleja-Alarcón, Juan Antonio [3], Sanz-Arnal, María [4], Vargas, Pablo [5], Lara, Francisco [4], Garilleti, Ricardo [6], Martin-Bravo, Santiago [7], Escudero Lirio, Antonio Marcial [8], Fernández-Mazuecos, Mario [4], Calatayud, Joaquín [9], G. Medina, Nagore [4].

The biotic component on the splitting and divergence of lineages: A case study in Carex.

Reproductive isolation leading to evolutionary divergence between allopatric lineages may stem from geographic isolation and/or divergent adaptation to different environmental conditions. The study of closely related allopatric species can provide insights into the relative importance of geographical versus ecological segregation in the divergence process. Assessing the macroevolutionary role of biotic interactions is one of the major challenges to a better understanding both large and fine scale biodiversity patterns. We examine the geography in combination with genetic, environmental, and biotic patterns across three very closely related species belonging to Carex sect. Phacocystis Dumort. (Carex reuteriana ssp. reuteriana, Carex reuteriana ssp. mauritanica, and Carex elata). We focused on inferring the mechanism driving their allopatric distribution across the Western Mediterranean region, particularly in the Iberian Peninsula. We used genotyping-by-sequencing to determine the phylogeographic patterns within the different taxa under study. We assessed the potential role of biotic factors using co-occurring species as proxy, i.e., other plants that co-inhabit with our study species in the same community. To this end, we relied on 1536 vegetation inventories containing real presences and absences of vascular plant taxa. We also studied abiotic factors using 38 bioclimatic variables. We explored the influence of both components using regularized generalized linear models in order to determine which variables contribute more to explain the observed allopatric distribution pattern. Furthermore, to approach the factors driving the lineage divergence of these studied taxa we studied in detail the relationships between individual genetic distances and biotic, abiotic and spatial distances of the communities where they inhabit. Phylogenomic results revealed a clear geographic structuring of the study taxa, accounting in total for six allopatric lineages within the Iberian Peninsula (two in each C. reuteriana subspecies, and another two within C. elata). Interestingly, the distributions of the three taxa are better predicted by other co-occurring species than by environmental factors. This suggests that biotic factors play an important role in the divergence of the study taxa. Supporting this idea, biotic, abiotic and geographical distances are significantly correlated with the genetic distances between populations of each taxon. Still, the independent effects of biotic distances explain the highest proportion of variance in C. elata’ s genetic distances; whilst geography has a major effect in Carex reuteriana ssp. reuteriana. By contrast, genetic distances of the subspecies mauritanica are better predicted by the combination of abiotic, biotic and geographic distances, with limited effects of any of these variables alone.

1 - Universidad Pablo de Olavide, Molecular Biology and Biochemical Engineering, Carretera Utrera, km1, s.n., Seville, Seville, 41013, España
2 - Universidad Autónoma De Madrid, Biología, Campus De Cantoblanco, Calle Darwin, 2, Madrid, 28049, Spain
3 - Universidad Autónoma De Madrid, Department of Biology, Campus De Cantoblanco, Calle Darwin, 2, Madrid, Madrid, 28049, Spain
4 - Universidad Autónoma De Madrid, Department of Biology, Campus De Cantoblanco, Calle Darwin, 2, Madrid, 28049, Spain
5 - Real Jardín Botánico, Department of Biodiversity and Conservation, Plaza de Murillo, 2, Madrid, 28014, Spain
6 - Universidad de Valencia, Department of Botany and Geology, Pharmacy, Spain
7 - Universidad Pablo de Olavide, Biología Molecular e Ingeniería Bioquímica, Ctra. de Utrera km 1, Seville, Seville, 41013, Spain
8 - Universidad de Sevilla, Departamento de Biología Vegetal y Ecología, Seville, Spain
9 - Universidad Rey Juan Carlos, Department of Biology, Geology, Physics and Inorganic Chemistry, Madrid, 28933, Spain

Environment Interactions
allopatric distribution
biotic drivers
abiotic drivers
co-occurring species
competitive exclusion
genetic distances.

Presentation Type: Poster
Number: PEC046
Abstract ID:520
Candidate for Awards:Ecological Section Best Graduate Student Paper

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