Episode Details

Two very different interpretations of the same set of data: one from Creationists and ID proponents, and the other from the scientists actually doing the work. Here, we talk to one of the latter.

A frequent talking point for creationists and Intelligent Design proponents in their anti-evolution rhetoric is a ground-breaking scientific project referred to as “the Long-Term Evolution Experiment.” Almost forty years ago, Dr. Richard Lenski began studying bacteria competing for limited energy resources (sugars) — generation after generation — looking for any genetic changes which gave any kind of advantage in that competition. His group have recently reached 76,000 generations, and documented many dozens of genetic mutations: rearrangements of regulatory pathways, elimination of genes which were no longer needed, introduction of new metabolic functions, shuffling of genetic information. In the process, there has been an incredible increase in fitness. This is much like someone deciding to train for a marathon — losing layers of fat, toning up muscles, revising their diet, replacing their normal wardrobe with ultra-light clothes and expensive runners, shaving seconds off of their run-time, increasing their stamina — and in the process, becoming a lean, mean running machine.

Nonetheless, creationists and ID proponents persist in diminishing the LTEE findings to just “breaking genes” and losing information.

After a brief introduction to the LTEE and the primary variables that they were monitoring (oxygen; fuel sources), we then talked to Dr. Zachary Blount, a member of the LTEE team who is continuing and broadening that research program, building on the findings and strategies of the LTEE. Points that we discussed included:

• the history of the LTEE: its founder, leaders, goals, and basic methodology
• twelve different “test tubes” of populations were kept separate, in order to see how the ancestral populations might try different evolutionary strategies
• they’ve now reached 76,000 generations; every 500 generations, they’ve frozen samples of the bugs so they can do follow-up experiments and/or recover from technical mistakes without