Creationists, or anti-evolutionists, are fond of declaring that the odds against evolution or of abiogenesis are great, so great as to make it almost impossible. Some say that the odds of the simplest organism forming “by chance” are 1 in 10340,000,000. Of course, to get those numbers they have to ignore the facts about how chemical changes occur or how evolution occurs and assume that everything happens at once, like an egg smash played in reverse.
However, scientists can play the numbers game, too. Doug Theobald has used phylogenetic software to calculate the odds that a group of proteins occurring in all life originated independently. You can read about it on Pharyngula.
…take a small set of known, conserved proteins that are shared in all organisms, not restricting ourselves to one kingdom or one phylum, but grabbing them all. In this paper, that data set consists of 23 proteins from 12 taxa in the Big Three domains: Bacteria, Archaea, and Eukarya. Then set up many different models to explain the relationships of these species. … And the winner is…common ancestry, with one branching tree!
Theobald distills it down to just the odds that bacteria have an independent origin from Archaea and eukaryotes:
But, based on the new analysis, the odds of that are “just astronomically enormous,” he said. “The number’s so big, it’s kind of silly to say it”–1 in 10 to the 2,680th power, or 10 followed by 2,680 zeros.
One in 102680…