Tuesday, November 28, 2017

New Stingray Species Described By Analysis of DNA Bar code

The blue-spotted maskray from Guadalcanal Island is anatomically and genetically different from Neotrygon kuhlii with which it was previously confused and it is genetically distinct from all other species in the genus Neotrygon. In this study it had its entire genome processed to determine if it was an entirely different species.
                                          On the basis of the nucleotide sequence at cytochrome oxidase 1 gene locus it is compared to other closely related counterparts. The study concludes that the CO1 gene locus is unique to the Neotrygon family and they possess a d distinct thymine group at nucleotide site 420 and a guanine at nucleotide site 522. By looking at the family they can tell if the two are in the same family and is the same species or a whole new species in the same family. Average nucleotide divergences between pairs of sequences within a lineage and net nucleotide divergences were estimated using a substitution model, the conclusion yielded negative results signifying that because of the slight difference in the CO1 gene site the Guadalcanal maskray stands alone from all other rays thought to be in its lineage.
                                          The implication of the genetic finds mean that there could be tons of more closely related species out there just waiting to be genetically tested. It is one thing to use observation and analyze morphometric and meristic characteristics of an organism, but as you assess organisms throughout their home range you might be able to see small coloration differences and other noticeable blurs and color variances. Genetic analysis eliminates all of this, no there is no confusion in the breakdown of the genome, and this is what in the field of marine biology is being utilized to help aid scientists and differentiate different species so everything can be maintained more efficiently.

                                          In conclusion, the Guadalcanal maskray only had three specimens to use to determine if it was an existing species or a related species, over time the specimens faded and the use of color was no longer a viable option, thus yes, morphometric and meristic are still accurate but it is very hard to tell when there isn’t a baseline for color, genetics was used to compare the CO1 loci and it was determined that the Guadalcanal mask ray is a new species. The nucleotide distance with other species in the genus Neotrygon is unique denoting something that hasn’t been seen concluding that the mask ray is in fact a new species.

1 comment:

  1. I've been studying marine biology as my major and find this article pretty awesome. I am sure there are so many different species that may look the same but are genetically different. It would be cool to sequence as much as possible in order to determine these differences.