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DNA Detectives Count Thousands of Fish Using a Glass of Water
vinces99 writes "A mere glass full of water from Monterey Bay Aquarium's 1.2 million-gallon Open Sea tank is all scientists really needed to identify the Pacific Bluefin tuna, dolphinfish and most of the other 13,000 fish swimming there. Researchers also discerned which of the species were most plentiful in the tank. Being able to determine the relative abundance of fish species in a body of water is the next step in possibly using modern DNA identification techniques to census fish in the open ocean, according to Ryan Kelly, University of Washington assistant professor of marine and environmental affairs, and lead author of a paper in the Jan. 15 issue of PLOS ONE. 'It might be unpleasant to think about when going for a swim in the ocean, but the water is a soup of cells shed by what lives there,' Kelly said. Fish shed cells from their skin, damaged tissues and as body wastes. 'Every one of those cells has DNA and if you have the right tools you can tell what species the cell came from. Now we're working to find the relative abundance of each species present,' he said."
Fish do piss in the water.
Fish use glasses of water?
Also, for the squeamish, fish, whales, penguins, sharks, jellyfish and manta rays don't use condoms. Not sure about crocodiles or wombats.
Couldn't stand the weather
Being able to determine the relative abundance of fish species in a body of water is the next step in possibly using modern DNA identification techniques to census fish in the open ocean
"the machine says that by far the pacific is full of a fish called...poly vinyl chloride. hm, that's a funny name."
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Is this the MPAA? Is this the RIAA? Is this the DMCA? I thought it was the USA!
Why would you do that to yourself, for Odin's sake, if you planned to ever sleep in a hotel bed again?
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
all scientists really needed to identify the Pacific Bluefin tuna, dolphinfish and most of the other 13,000 fish swimming there
What about species no-one knows about?
Questions raise, answers kill. Raise questions to stay alive.
Fish do piss in the water.
As far as I can see, the next logical step for the technique as outlined in TFA is to take a glass of sewage from a city sewage treatment center and analyze for the % of the number of human beings with a particular type of disease (HIV, TB, Polio or whatever).
Muchas Gracias, Señor Edward Snowden !
Followed swiftly by fish taxation.
Requiem for the American Dream
http://www.youtube.com/watch?v=9jfndCtV0gw
- In Soviet Korea, only old people loose all their bases to Natalie Portman's petrified hot grits overlords.
What about species no-one knows about?
As with other "soup" DNA techniques those species that they do not have DNA information for (I'm using this term loosely) would simply be separated by their genetic differentiation between each other. This is one of the primary problems with identifying species with "Soup" because organisms can be the same distance apart genetically but some may be different species morphologically and others may be the same.
In a simplified example say you have organisms A, B and C. A and B are closest genetically, A and C are furthest away while B and C are the same distance away from each other. One would look at this and assume A, B and C are separate species. However you then observe in the wild that B and C are able to breed, perhaps B and C are one species while A is separate? This is one of many examples of how genetic information can mislead species information
Unfortunately speciation is complicated and often not linear which leaves a confusing genetic trail. Fortunately, data telling us the genetic variation of an area can still be very useful for many scientific questions. Not to mention the usefulness of being able to identify the presence/ absence of well known species.
Now you've ruined my winter vacation, and while I'm sitting on the beach sipping rum I'll know if I go in the ocean I'll be covered in fish goo.
*sigh* I'll just have to have another rum. Purely to fight infections you understand.
Lost at C:>. Found at C.
But can it tell them when they're gonna need a bigger boat?
http://www.wingclips.com/movie-clips/jaws/a-bigger-boat
Pay no attention to the man behind the curtain with all your metadata.
In a simplified example say you have organisms A, B and C. A and B are closest genetically, A and C are furthest away while B and C are the same distance away from each other. One would look at this and assume A, B and C are separate species. However you then observe in the wild that B and C are able to breed, perhaps B and C are one species while A is separate? This is one of many examples of how genetic information can mislead species information
Fine and dandy.
Now, let's take another case: you know species A, you know nothing about B and C. Thus you can tell "A was here" but... can you tell there are other (exactly) two that "were here" as well? Maybe they were only one, maybe more than two. How can you tell?
Questions raise, answers kill. Raise questions to stay alive.
Fine and dandy.
Now, let's take another case: you know species A, you know nothing about B and C. Thus you can tell "A was here" but... can you tell there are other (exactly) two that "were here" as well? Maybe they were only one, maybe more than two. How can you tell?
Welp, that's exactly the problem, that isn't to say there aren't other methods though. For example you could see how much genetic differentiation there is between known species in the area and make assumptions based on that. You could also use other types of DNA, mitochondrial DNA for example which may tell a different story.
Fact is, taxonomists are always fighting about which species is which, sometimes with fruition. DNA, while it is very useful in determining one species from another has added to the questions about what really defines a species and what differentiates one from the other. Even morphologically there has been debate as to whether the two specimens you are holding are one species or two. Take the Eclectus Parrot for an early example, the male is bright green whereas the female is red/purple, scientists thought them to be separate species until they actually saw them mating. Things can get even more confusing when species don't physically mate with each other (think pollen and plants) or when they mate between species. Hopefully this type of science will take us closer to the answer.
On the other hand, personally I like these kind of studies for other uses like saying "Hey! This spot has way more genetically different organisms, maybe it's more important to not pollute it"
It't a good thing all fish are the same size and shed cells at the same rate so we can directly compare between species...
Imagine what you could do with a sample from the local sewage treatment facility!
This is really cool, great use of modern tech! I am curious as to which species they could not detect, and why they think that is? Too small of a population? Too small in size? Sampling size possibly not big enough? It seems like they would want to answer these questions as well.
I would also imagine that the distance of a fish from the sample taken will also have an effect on the amount of cells from each fish collected in the sample (for instance, as the distance increases more of the cells will either deteriorate or settle down or wind up being absorbed by another organism?). Since different fish may hang out in different parts of the ocean depending on climate, depth of water, and other factors taking a sample only from one specific location may skew the results. Scarce fish in the region where the sample was taken may appear more abundant than more abundant fish slightly further away. Care must be taken to account for this.
I just want to know what the % of human DNA was found in the sample, that will tell us how polluted the bay is.
And you can use the same method at the sewage stations to be able to count the number of individuals in a town or city, then separate out the DNA of everyone that's there illegally and track them down.
Nobody will be safe from our civil masters.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
So how many salt water fish would they find in the sewers of every city. I think that just because the dna is present doesn't imply or cause the critter to be present. At least not alive.
DNA Detectives Count Thousands of Fish Using a Glass of Water
Researchers also discerned which of the species were most plentiful in the tank.
Someone doesn't know what counting is (the article had the good grace to put it in scare quotes).
systemd is Roko's Basilisk.
You'll vastly overestimate the presence of any fish with ichthyosis.
"I never drink water. Fish fuck in it."
If only academic departments/institutions collaborated or communicated a little bit more, maybe the research dollar would go a little further?
Cheers.
G
PADI instructor 636522
we've all seen that movie, NO THANKS.