Courtesy of the journal Science, there’s a new report about a type of fish that has quickly adapted to living in the PCB rich waters of the Hudson: Mechanistic Basis of Resistance to PCBs in Atlantic Tomcod from the Hudson River.
I’ll leave the hardcore analysis to the science blogs. Perhaps the fact that the ID blog Evolution News and Views has already explained how this exactly fits Micheal Behe’s thesis will prompt them to action. For now, I’ll stick with the press release.
Basically, General Electric dumped large amounts of Polychlorinated biphenyls, or PCBs, into the Hudson River, from the late 1940s until they were banned in 1976. PCBs are complex and dangerous toxins. One particular fish, the Atlantic tomcod, is a bottom feeder and well placed to suck up lots of nummy PCBs.
Tests of the small fish show “levels of the chemical in its liver are among the highest reported in nature.” And yet, they survive. The researchers found that tomcod in the polluted waters carry a genetic variation that blunts the toxic effect of the PCBs, and that this variation has become much more common in just the past fifty years.
Slight alterations—the deletion of only six base pairs in DNA of the AHR2 gene—appear to protect tomcod from PCBs, according to the study. Normally, when unaltered AHR2 binds to PCBs, it triggers a cascade of reactions that transmit the toxic effects of the compound. However, the study found that PCBs bind poorly to the variant AHRs, which apparently blunts the chemicals’ effects.
Tomcod from cleaner waters occasionally carried mutant AHR2, suggesting that these variants existed in minor proportions prior to PCB pollution, says Dr. [Isaac] Wirgin. After the chemical was released, tomcod carrying the mutation had an advantage over others in the population because PCBs otherwise lead to lethal heart defects in young fish. The study’s findings suggest that this advantage drove genetic changes in these fish over some fifty years. “We think of evolution as something that happens over thousands of generations,” says Dr. Wirgin. “But here it happened remarkably quickly.”
Ironically, the fish may not do so well once the EPA’s PCB cleanup starts back up this spring. National Geographic points out that this will help some of the tomcod’s predators, since the fish are currently little deadly packets of PCBs.
However, as someone who lives right on the Hudson, I’d like to say the tomcod can deal. Get that crap out of here!
(h/t to All Over Albany)
Cool :-) I read the
IDiot PropagandaEvolution News and Views article too – and my goodness me, Straws! They’re grasping at them! They even dare to suggest that ID predicted this, it’s a mechanistic change. Apparently “mechanistic change” is a helpful new phrase for them because, depsite them not knowin what it means, it sounds like it’s not really evolution. Arseholes.Mechanistic basis, how the f*ck does it work?
This is an interesting story. But I doubt it will make much difference to the ID crows. They will say that this is an example of “micro-evolution”, and not “macro-evolution”. This is a safe position to take because they will say that there is no present evidence of evolution happening right now, but all evidence of evolution happening right now, because the process is so slow, can be called “micro-evolution”.
There problem of course is that they also deny every process that makes evolution possible, such as adding new genetic information, beneficial mutations, ect. However these are exactly what are needed to have even “micro-evolution”. But as far as this story goes, ID will not find it remarkable.
Well, it can be called micro-evolution, but doing so makes the term even more meaningless than it already was, since there are plenty of observations of speciation in nature.
But of course, those events weren’t cats turning into dogs, so obviously that’s not “macro-evolution.”
Damn I hate IDiots.
As said above. To the theostards this means nothing.
The fish did not evolve into a horse with intermediate fossils so it is the way g0d made it.
But an interesting adaption that shows the power of evolution over the short term.
Good info and post
I’m no bioligist or even a scientist, but the ID argument seems silly. What I got out of it was that it can’t be evolution because or the deletion of six base pairs. This makes it a negative mutation which has other consequences. It seems likely to me that this is a small evolutionary step and that probably isn’t over. There will be further natural selection and more changes in the tomcod.
Fit’s perfectly with those ”Faithful” Idiots. After all, faith is ……the concept of: Not wanting to deal with reality.