Molecular Phylogenetics and Molecular Phylogenetics and Historical Biogeography among Historical Biogeography among

Salamandrids of the “True” Salamandrids of the “True” Salamander Clade: Rapid Salamander Clade: Rapid

Branching of Numberous Highly Branching of Numberous Highly Divergent Lineages in Divergent Lineages in

Mertensiella luschani Mertensiella luschani Associated Associated with the Rise of Anatoliawith the Rise of Anatolia

David W. Weisrock, J. Robert Macey, David W. Weisrock, J. Robert Macey, Ismail H. Ugurtas, Allan Larson, and Ismail H. Ugurtas, Allan Larson, and

Theodore J. PapenfussTheodore J. Papenfuss

QuestionsQuestions

1. Why is there such 1. Why is there such diversity within a diversity within a relative small amount relative small amount of space of the of space of the Mertensiella luschani Mertensiella luschani in southwestern in southwestern Turkey (Anatolia)?Turkey (Anatolia)?

QuestionsQuestionsNeed a comparison Need a comparison group: group: Mertensiella Mertensiella caucasicacaucasica

2. Is 2. Is Mertensiella Mertensiella really a really a monophyletic group?monophyletic group?

““True” SalamandersTrue” Salamanders

HypothesesHypotheses Mertensiella Mertensiella is not a is not a

monophyletic group.monophyletic group. Two separate vicariant Two separate vicariant

events occurred between events occurred between Anatolia and Europe.Anatolia and Europe.

MethodsMethods Collected genomic DNA from liver or muscle from the “true” Collected genomic DNA from liver or muscle from the “true”

salamanders and the out group (newts)salamanders and the out group (newts) Amplified the genomic DNA, purified/isolated and re-Amplified the genomic DNA, purified/isolated and re-

amplified. amplified. Aligned DNA Sequences: 20 mitochondrial DNA sequencesAligned DNA Sequences: 20 mitochondrial DNA sequences

-Non-alignable sequences were omitted because of -Non-alignable sequences were omitted because of considerable length variationconsiderable length variation

Analytical MethodsAnalytical Methods

Estimated parsimonious phylogenetic treesEstimated parsimonious phylogenetic trees Bootstrap resamplingBootstrap resampling Decay indices Decay indices Wilcoxon signed-ranks test (examine the Wilcoxon signed-ranks test (examine the

statistical significance of the overall shortest statistical significance of the overall shortest tree)tree)

Four-taxon test of Felsenstein (examine Four-taxon test of Felsenstein (examine statistical significance of phylogenetic statistical significance of phylogenetic groupings)groupings)

Single most Single most parsimoniousparsimonious tree tree

generatedgenerated

Phylogram of the single most Phylogram of the single most parsimonious treeparsimonious tree

ResultsResults

The overall shortest depicts the “true” The overall shortest depicts the “true” salamanders as monophyletic relative to salamanders as monophyletic relative to the out group taxa sampled. When this the out group taxa sampled. When this tree is compared to the shortest tree is compared to the shortest alternative tree showing the “true” alternative tree showing the “true” salamanders as a nonmonophyletic salamanders as a nonmonophyletic group, this alternative is rejected by the group, this alternative is rejected by the Wilcoxon signed-ranks test using the Wilcoxon signed-ranks test using the two-tailed test.two-tailed test.

ResultsResults

The genus The genus MertensiellaMertensiella is not resolved is not resolved as a monophyletic group in the overall as a monophyletic group in the overall shortest tree. When the overall shortest tree. When the overall shortest tree is compared to the shortest tree is compared to the shortest alternative trees depicting a shortest alternative trees depicting a monophyletic monophyletic MertensiellaMertensiella, the , the alternative trees are rejected by the alternative trees are rejected by the Wilcoxon signed-ranks test using the Wilcoxon signed-ranks test using the two tailed test.two tailed test.

ResultsResults

The overall shortest tree places The overall shortest tree places M. M. luschaniluschani as the sister taxon to the genus as the sister taxon to the genus SalamandraSalamandra. When this tree is compared . When this tree is compared to the shortest alternative tree in which to the shortest alternative tree in which M. luschaniM. luschani and and SalamandraSalamandra do not form do not form a monophyletic group, this alternative a monophyletic group, this alternative tree is rejected by the Wilcoxon signed-tree is rejected by the Wilcoxon signed-ranks test using the two tailed test.ranks test using the two tailed test.

ResultsResults

The overall shortest tree places The overall shortest tree places M. M. caucasicacaucasica and and Chioglossa Chioglossa as sister as sister taxa. When this tree is compared to taxa. When this tree is compared to the shortest alternative trees in which the shortest alternative trees in which these taxa do not form a monophyletic these taxa do not form a monophyletic group, these alternatives are rejected group, these alternatives are rejected by the Wilcoxon signed-ranks test by the Wilcoxon signed-ranks test using the one tailed test.using the one tailed test.

ResultsResults

Three well-supported clades within Three well-supported clades within M. M. luschani luschani and three additional lineages are and three additional lineages are recovered with only weak support. recovered with only weak support.

The four-taxon test of Felsenstien showed The four-taxon test of Felsenstien showed that there is strong evidence suggesting that there is strong evidence suggesting hard polytomy.hard polytomy.-hard polytomy=simultaneous branching -hard polytomy=simultaneous branching from a common ancestral lineagefrom a common ancestral lineage-soft polytomy=successive branching of -soft polytomy=successive branching of lineages that have relatively short lineages that have relatively short intervals of time between themintervals of time between them

DiscussionDiscussion

Molecular clockMolecular clock

Biogeographical event 1Biogeographical event 1

Represents plausible geographical Represents plausible geographical evidence for the divergence of evidence for the divergence of Chioglossa Chioglossa lusitanicalusitanica and and Mertensiella caucasicaMertensiella caucasica

Biogeographical event 2Biogeographical event 2

Represents plausible geographical Represents plausible geographical evidence for the divergence of genus evidence for the divergence of genus SalamandraSalamandra and and Mertensiella luschaniMertensiella luschani

Genetic Diversity in Tectonic Collision ZonesGenetic Diversity in Tectonic Collision Zones The southern margin of Anatolia represents a collision zone between ancient The southern margin of Anatolia represents a collision zone between ancient

Gondwanan tectonic fragments that are sandwiched between Laurasian Gondwanan tectonic fragments that are sandwiched between Laurasian plates to the north and the Gondwanan fragment of Arabia to the south. The plates to the north and the Gondwanan fragment of Arabia to the south. The intense Miocene mountain building in Anatolia results from the Arabian intense Miocene mountain building in Anatolia results from the Arabian collision. The high levels of genetic diversity detected in collision. The high levels of genetic diversity detected in M. luschani M. luschani across a across a narrow region (;350 km) of this tectonic collision zone may represent a narrow region (;350 km) of this tectonic collision zone may represent a common pattern in geologically active areas. Conservation efforts should be common pattern in geologically active areas. Conservation efforts should be focused in collision zones for two reasons: (1) tectonic plates introduce new focused in collision zones for two reasons: (1) tectonic plates introduce new faunal elements, potentially increasing diversity, and (2) mountain building in faunal elements, potentially increasing diversity, and (2) mountain building in suture zones is important in causing high levels of genetic diversity among suture zones is important in causing high levels of genetic diversity among faunal elements. Future studies assessing genetic variation in taxa that occur faunal elements. Future studies assessing genetic variation in taxa that occur in geologically active areas will be important in testing this hypothesis.in geologically active areas will be important in testing this hypothesis.

Questions?Questions?