The latest on Junk DNA
Scientists at the University of California at Santa Cruz compared the DNA sequences of humans and of other animals (now that so many have been sequenced), and have found a surprising amount of "common DNA" – DNA that scientists have assumed was "junk DNA" because it did not appear to serve any purpose. The fact that these DNA sequences have not mutated in the millions of years since our various lineages diverged means that it must be meaningful, though scientists do not yet know what that purpose is. Over so many millions of years, sooner or later there would be some random mutations in these DNA sequences, and if they didn’t matter, they would keep accumulating until those sequences would bear little resemblance to each other, when you go across different genus and species. And yet these sequences have remained remarkably similar
My theory is that the purpose of this DNA is so basic that scientists are not seeing the forest for the trees. I think it was in the movie Contact, with Jodie Foster, that the key to decoding the alien transmission was to determine that the Morse code at the beginning was prime numbers or something like that. Some space probe out there right now that’s looking for intelligent life has other mathematical equations such as 1+1=2 – equations that set the tone for "obvious" in any culture advanced enough to know what "math" is. If these aliens can decode our representation of 1+1=2, maybe they’ll stop by for a visit. Other SETI (search for extraterrestrial intelligence) activities include "broadcasting pi" over radio waves – another culture-free constant.
I think we are going to find out that this common DNA defines the most basic operations that the rest of the DNA needs to perform. It can identify different elements to be used in making proteins, describe what proteins are, how to bind two atoms together to start making a molecule, whatever. When you read a recipe, it often says things like "brown 1 lb of ground beef". But there are a whole host of implied instructions: take a skillet out of the cupboard (a skillet is one of the round, flat metal things with the long handle), place it on the stove, take the package of ground beef out of the refrigerator, open it up, crumble the ground beef into the skillet, throw the packaging away, turn the heat control dial on the stove, under the burner that you put the pan on, until it is "on" and you see flames (assuming it is a gas stove), etc. Every animal’s DNA has got to have the basic instructions to do its job. It’s not like it goes to DNA School to learn how to do that, the way our great chefs go to the Culinary Institute, or the lesser of us learn from our families and our home economics classes.
And that is the miracle of DNA: that everything – and I mean the entire and complete body of knowledge necessary to create and maintain you – is right there, all packaged up, in each and every cell in your body. Amazing.
10:09:20 PM 
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