Friday, May 16, 2014

[Mammalogy • 2014] Biogeography and Taxonomy of Extinct and Endangered Monk Seals (Monachus & Neomonachus gen. nov.) Illuminated by Ancient DNA and Skull Morphology


recently extinct Caribbean monk seal, now classified as Neomonachus tropicalis
illustration: Peter Schouten

Abstract
Extinctions and declines of large marine vertebrates have major ecological impacts and are of critical concern in marine environments. The Caribbean monk seal, Monachus tropicalis, last definitively reported in 1952, was one of the few marine mammal species to become extinct in historical times. Despite its importance for understanding the evolutionary biogeography of southern phocids, the relationships of M. tropicalis to the two living species of critically endangered monk seals have not been resolved. In this study we present the first molecular data for M. tropicalis, derived from museum skins. Phylogenetic analysis of cytochrome b sequences indicates that M. tropicalis was more closely related to the Hawaiian rather than the Mediterranean monk seal. Divergence time estimation implicates the formation of the Panamanian Isthmus in the speciation of Caribbean and Hawaiian monk seals. Molecular, morphological and temporal divergence between the Mediterranean and “New World monk seals” (Hawaiian and Caribbean) is profound, equivalent to or greater than between sister genera of phocids. As a result, we classify the Caribbean and Hawaiian monk seals together in a newly erected genus, Neomonachus. The two genera of extant monk seals (Monachus and Neomonachus) represent old evolutionary lineages each represented by a single critically endangered species, both warranting continuing and concerted conservation attention and investment if they are to avoid the fate of their Caribbean relative.
Keywords: Ancient DNA, extinction, mitochondrial DNA, Panamanian Seaway, Phocidae, systematics


Martin-Scheel D, Slater GJ, Kolokotronis S-O, Potter CW, Rotstein DS, Tsangaras K, Greenwood AD, Helgen KM. 2014. Biogeography and Taxonomy of Extinct and Endangered Monk Seals Illuminated by Ancient DNA and Skull Morphology. ZooKeys 409: 1-33. DOI: dx.doi.org/10.3897/zookeys.409.6244

Extinct relative helps to reclassify the world's remaining two species of monk seal
Scientists uncover new marine mammal genus, represented by single endangered species http://news.mongabay.com/2014/0514-hance-monk-seal-genus.html