Monday, March 4, 2013

2 Million DNA barcodes

Last Friday more or less on the q.t. BOLD surpassed the 2 Million sequence mark.


This is quite an accomplishment for the young discipline DNA Barcoding especially given the amount of collateral information connected to every record. However, the International Barcode of Life Project (iBOL) has much greater goals. Until 2015, iBOL participants want to gather DNA barcode records from five million specimens, representing at least 500 000 species. More than a million sequences have been added to the barcode library since the launch of iBOL in 2010. It is obvious that work needs to be scaled up to reach the five million target by the end of 2015.

What seems to be already within reach is the goal to barcode at least 500 000 species by 2015 as there are now records for more than 300 000 barcode clusters of plant and animals.

After seeing these number I was immediately interested in more details. I obtained some numbers from BOLD's taxonomy browser to calculate the taxonomic breakdown of the formal species barcoded. The result - two simple pie charts depicting coverage of animal phyla and plant divisions:

Formally described animal species with DNA Barcodes on BOLD
It is not surprising that more than 3/4 of all formal animal species with a DNA Barcode are arthropods. Not only is it the most speciose phylum in the animal kingdom but also the target of a lot of DNA Barcoding activities such as the campaign to barcode all lepidoptera.

What is nice to see is that other groups are catching up. One example are the chordates. To this date the library contains a third of all known fish species and amphibians respectively, almost half of each the birds and the mammals, and a quarter of the reptilians. The recent announcement that CBOL has been granted funds from Google to barcode a large number of endangered animals lets me believe that these numbers will likely go up rapidly.

Formally described plant species with DNA Barcodes on BOLD
Another impressive figure shows the progress of plant DNA Barcoding. Let's not forget that the formal acceptance of the rbcL and matK chloroplast genes as DNA Barcodes for land plants dates back just 4 years. 13% of the known green plant species have been added to the DNA Barcode library.

Within 10 years we have amassed DNA Barcode records for more than 10% of all described species. Now that is quite an accomplishment!

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