Sunday, September 16, 2012

Common ancestry of life

GTGCCAGCAGCCGCGGTAATTCCAGCTCCAATA GCGTATATTAAAGTTGCTGCAGTTAAAAAG

It looks like gibberish, but this DNA sequence is truly remarkable. It is present in all the cells of your body, in your cat or dog, the fish on your plate, the bees and butterflies in your garden and in the bacteria in your gut.

In fact, wherever you find life on Earth, from boiling hot vents deep under the sea to frozen bacteria in the clouds high above the planet, you find this sequence. You can even find it in some things that aren't technically alive, such as the giant viruses known as mimiviruses.

This sequence is so widespread because it evolved in the common ancestor of all life, and as it carries out a crucial process, it has barely changed ever since. Put another way, some of your DNA is an unimaginable 3 billion years old, passed down to you in an unbroken chain.

New Scientist 15 September 2012


No comments: