Can’t quite figure out what this article is trying to say. It describes the traits of the tuatara—straightforward and factual.
It also asserts that “ a few regions of tuatara DNA appear to be evolving at hyperspeed <http://www.cell.com/trends/genetics/abstract/S0168-9525%2808%2900003-6> , possibly the fastest mutation rate yet clocked in a vertebrate genome.” And, “The quick-changing sequences are limited to so-called neutral regions of the tuatara’s DNA, affecting filler codes, rather than the molecular blueprints for how to build a tuatara.” This is where things get a little vague and nonspecific. What do they mean by evolving at hyperspeed? What are neutral regions? It almost sounds as if they’re referring to ‘junk’ DNA. And, since the tuatara hasn’t changed for ‘hundreds of millions of years’, what would be the evolutionary significance of these regions evolving at hyperspeed? The creatures are still tuataras. Are the authors trying to imply that the tuatara is getting ready to evolve into a higher, more complex kind of organism? Do the authors see the mutations as being good or deleterious?
Unfortunately, I don’t have easy access to the full study linked to in the NYT article—perhaps it would answer some of my questions. The NYT article itself doesn’t seem to be much more than an interesting description of an unusual animal, with an obligatory reference to evolution thrown in.
http://jvi.asm.org/cgi/content/abstract/81/23/12979
This study found no beneficial mutations at all.
http://www.nature.com/nature/journal/v467/n7315/abs/nature09352.html
Study of fruit flies over 600+ generations finds a resistance to change. The fruit flies remained fruit flies.
Susan
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