Thursday, May 14, 2009

Bloody cool News!

Pic: Frederic Buyle


Yes this is the language of Molecular Analysis!

From Species Delineation and Evolutionary History of the Globally Distributed Spotted Eagle Ray (Aetobatus narinari)
Vincent P. Richards, Marcy Henning, Wayne Witzell, and Mahmood S. Shivji

Molecular analyses are resolving many taxonomic uncertainties, including revealing that species once thought to cover wide geographic areas are often complexes comprising 2 or more genetically distinct species.
In addition to providing taxonomic clarity and more accurate biodiversity assessments, such findings have management and conservation ramifications as many of the newly identified species may have limited ranges and relatively small population sizes rendering them more vulnerable to human impact.
Consequently, the accurate delimitation of species boundaries is an important conservation need, especially for exploited species.

First the Manta Rays, now this.

The Spotted Eagle Ray (Aetobatus narinari), a large coral reef–associated batoid of conservation concern, is currently described as a single, circumglobally distributed species.
However, geographic
differences in its morphology and parasite diversity have raised unconfirmed suspicions that A. narinari may constitute a species complex.
We used 1570 bp of mitochondrial and nuclear sequence
data (cytochrome b, cytochrome c oxidase subunit I, and internal transcribed spacer 2) to assess the validity of A. narinari as a single cosmopolitan species and infer its evolutionary history. Specimens from 4 major geographic regions were examined: the Central Atlantic, Eastern Pacific, Western Pacific, and Central Pacific.

Phylogenies described 3 distinct, reciprocally
monophyletic lineages with no genetic exchange among regions. Based on combined genealogical concordance and genetic distance criteria, we recommend that the Western/Central Pacific lineage be recognized as a distinct species from lineages in the Central Atlantic and Eastern Pacific. The latter 2 lineages, separated by the Isthmus of Panama, are proposed as subspecies.
A basal
position in phylogenetic analyses and statistical parsimony results support an Indo-West Pacific origin for the A. narinari species complex, with subsequent westerly dispersal around the southern tip of Africa into the Atlantic and then into the Eastern Pacific.

Original paper (including the gibberish at the top) here.
Just stunning!

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