Galápagos and Californian sea lions are separate species: Genetic analysis of the genus Zalophus and its implications for conservation management

@article{Wolf2007GalpagosAC,
  title={Gal{\'a}pagos and Californian sea lions are separate species: Genetic analysis of the genus Zalophus and its implications for conservation management},
  author={Jochen B. W. Wolf and Diethard Tautz and Fritz Trillmich},
  journal={Frontiers in Zoology},
  year={2007},
  volume={4},
  pages={20 - 20}
}
BackgroundAccurate formal taxonomic designations are thought to be of critical importance for the conservation of endangered taxa. The Galápagos sea lion (GSL), being appreciated as a key element of the Galápagos marine ecosystem, has lately been listed as 'vulnerable' by the IUCN. To date there is, however, hardly any scientific evidence, whether it constitutes a separate entity from its abundant Californian neighbour (CSL). In this paper, we delineate the taxonomic relationships within the… 
Phylogeography of California and Galápagos sea lions and population structure within the California sea lion
TLDR
A Minimum Spanning Network showed a strong phylogeographic signal with two well-defined clusters, Z. californianus and Z. wollebaeki, supporting the existence of two genetically distinct species with an estimated divergence time of ~0.8 Ma, and within-population structure for the California sea lion based on mitochondrial DNA.
Tracing early stages of species differentiation: Ecological, morphological and genetic divergence of Galápagos sea lion populations
TLDR
This study challenges the view that geographical barriers are strictly needed for the build-up of genetic divergence and suggests a key role of intra- as well as inter-specific niche segregation in the evolution of genetic structure among populations of a highly mobile species under conditions of free movement.
Pinniped taxonomy: review of currently recognized species and subspecies, and evidence used for their description
TLDR
Morphologic and genetic criteria used to recognize pinniped species and subspecies are evaluated individually for all taxa in the three families: Otariidae (sea lions and fur seals), Odobenidae (walruses) and Phocidae (seals).
Biogeography and taxonomy of extinct and endangered monk seals illuminated by ancient DNA and skull morphology
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Phylogenetic analysis of cytochrome b sequences indicates that M. tropicalis was more closely related to the Hawaiian rather than the Mediterranean monk seal, and the Caribbean and Hawaiian monk seals are classified together in a newly erected genus, Neomonachus.
Phylogenomic Discordance in the Eared Seals is best explained by Incomplete Lineage Sorting following Explosive Radiation in the Southern Hemisphere
TLDR
High-coverage genome-wide sequencing is used for 14 of the 15 species of Otariidae to elucidate the phylogeny of the family and its bearing on the taxonomy and biogeographical history and finds a fully supported species tree that agrees with the few well-accepted relationships and establishes monophyly of the genus Arctocephalus.
Phylogenomic Discordance in the Eared Seals is best explained by Incomplete Lineage Sorting following Explosive Radiation in the Southern Hemisphere.
TLDR
High-coverage genome-wide sequencing is used for 14 of the 15 species of Otariidae to elucidate the phylogeny of the family and its bearing on the taxonomy and biogeographical history and finds a fully supported species tree that agrees with the few well-accepted relationships and establishes monophyly of the genus Arctocephalus.
Elephant Seal (Mirounga sp.) from The Pleistocene of the Antofagasta Region, Northern Chile
ABSTRACT The genus Mirounga is the largest living member of the Phocidae family (true seals) and includes two species: M. angustirostris and M. leonina. These species exhibit a noticeable
Extralimital Distribution of Galapagos (Zalophus wollebaeki) and Northern (Eumetopias jubatus) Sea Lions in Mexico
Global pinniped distribution is greatly determined by changes in sea surface temperature. El Nino events also have been reported to directly influence pinniped distribution. These events have
Fine-scale matrilineal population structure in the Galapagos fur seal and its implications for conservation management
TLDR
A population genetic survey in the Galapagos fur seal, Arctocephalus galapagoensis, an endangered pinniped endemic to a small geographic range, finds remarkably strong fine-scale matrilineal population structure, with 33.9 % of the mtDNA variation being partitioned among colonies separated by as little as 70 km swimming distance.
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TLDR
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TLDR
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TLDR
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