14 October 2009

Barcode of Life

I've written a lot about the fish collection process (and about the reservations I have had with it), but not that much about why it's being done. The samples that have been collected here are part of the much larger "Barcode of Life" project. The idea is to catalog every living species in the world with a genetic "barcode." Once it's complete, you will be able to take a sample of any living organism, run it through the barcode process, and get a positive taxonomic identification output. It is different from a genome (where the entire genetic code of an organism is sequenced). Instead, only enough genes to identify the organism are sequenced (saving time and money). But what good is it to be able to identify species in this way? The benefit of having a database of genetic "barcodes" may not be obvious (it wasn't for me).

The truth is, I'm not really all that familiar with the project. I can, however, share some of what I've learned about it in the last few days. First of all, it will be useful in the enforcement of some environmental regulations. Enforcement agencies can (and actually already are) using it to crack down on the illegal fish and "bush meat" trade. For example, just before our Smithsonian visitors came here the director of the project was sent a fillet of fish by the government body that regulates the fish trade (the EPA or FDA?), seized from a distributor suspected of selling an endangered species. By running a sample through the test, he identified the species from an otherwise indistinguishable fillet and informed the regulators whether or not any laws were being broken. In that particular case, it turned out that endangered fish was not being sold (though, I think some labeling laws were probably broken).

Also, the barcode project has been extraordinarily effective if identifying new species. Currently, most taxonomic identification is a visual process. Humans have to physically look at organisms and distinguish them by their anatomy and markings. And humans, of course, make a lot of mistakes. Species can look the same, but be genetically very different. An example is the recently discovered species of Soapfish I mentioned in an earlier post.

Rypticus subbifrenatus

Rypticus sp.

Both of these photos are from the same field ID guide, improperly listed as color variations of the same species. Actually, they are genetically quite different.

Another area where it has been helpful is in the identification of species throughout their lifecycles. Fishes, in particular, can vary dramatically as they transition from larval, through juvenile, intermediate, and terminal phases. I always wondered how anybody ever knew, for example, a juvenile Smooth Trunkfish was actually a Smooth Trunkfish. They don't look anything alike. In the past it required identifying enough specimens in transition to reveal the link or (believe it or not) raising them in captivity and observing the transition! I was told that they are finding that numerous species previously thought to be unique are simply juvenile phases of other known fish. Since genetic code remains the same no matter what phase the species is in, they can always be identified by their genetic barcode.

Juvenile Phase

Terminal Phase

Okay, they resemble each other a little in the photos, but in real life making the connection is much more difficult.

Probably the most exciting application for the barcode of life (at least in my opinion) is still many years from actually being available. I think of it as sort of a field ID "iPhone application," or something like a Star Trek "tri-corder" for identifying species. It would be a handheld genetic sequencer that could instantly pull up all sorts of pertinent information on whatever living thing you can manage to get your hands on (probably easier to use with plants than most animals). I imagine amateur naturalists of the future carrying around these things in place of the visual ID books we use now. It sounds like something that belongs in science fiction, but it turns out that small field sequencers already exist for scientists, and the director of the Smithsonian lab predicts that a consumer friendly version is probably only 10 years away. Once this technology is out there, its potential is huge (Imagine you're a researcher interested in a rare insect. You flag it in the barcode database to be notified each time the record is accessed, an amateur naturalist finds it in the field an runs it through the sequencer out of curiosity, he or she gets all the information they are interested in as well as a personal message from you asking them to collect the data necessary for your research. It's collaborative research taken to a whole new level. It's like wikipedia on steroids).

The Barcode project promises a lot of very exciting things, the extent of which has probably yet to be conceived. Knowing just some of its potential makes me glad that I got the chance to be part of it, if even in the smallest way.

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