Thursday, August 16, 2007

LUCA was an orgy

For many years, LUCA, (the hypothetical "Latest Universal Common Ancestor" of all life on earth), was believed to be a tiny and primitive bacteria. It lived all by itself, 3.8 billion years ago, in the metallic soup and volcanic gas of ancient earth.

Eventually, somehow, it evolved into the three Domains of Life - bacteria, archaea, and eukaryota (multicellulars like us).

But a new view says otherwise . . .

Genetic studies indicate that all the DNA in the three Domains today show signs of "contamination" from the other Domains. And this "gene-swapping" happened many billions of years ago.

Old View: Lonely little LUCA works hard to grow itself into all the lifeforms on earth.

New View: A crowd of LUCAs, swapping genes in a primordial orgy! And their mutant offspring? They join the party too!