She pushed that thought aside. She would not give up. Whatever the reason for the current cooperation, Lisa intended to use it to her best advantage.

Lisa nodded to Anna as she approached. "Okay, I think I have a layman's grasp on the larger picture here. But you raised something earlier that's been nagging at me."

Dropping the books to the table, Anna settled into a seat. "What is that?"

"You mentioned that you believed the Bell controlled evolution." Lisa waved her hand across the breadth of books and manuscripts on the table. "But what I see here is just some mutagenic radiation that you've tied to a eugenics program. Building a better human being through genetic manipulation. Were you just being grandiose when you used the word e vo/ution?"

Anna shook her head, taking no offense. "How do you define evolution, Dr. Cummings?"

"The usual Darwinian way, I suppose."

"And that is?"

Lisa frowned. "A gradual process of biological change…where a single-celled organism spread and diversified into the present-day range of living organisms."

"And God has no hand in this at all?"

Lisa was taken aback by her question. "Like in creationism?"

Anna shrugged, eyes fixed on her. "Or intelligent design."

"You can't be serious? Next you'll be telling me how evolution is just a theory."

"Don't be silly. I'm not a layman who associates theory with a 'hunch' or 'guess.' Nothing in science reaches the level of theory without a vast pool of facts and tested hypotheses behind it."

"So then you accept Darwin's theory of evolution?"

"Certainly. Without a doubt. It's supported across all disciplines of science."

"Then why were you talking about—"

"One does not necessarily rule the other out."

Lisa cocked up one eyebrow. "Intelligent design and evolution?"

Anna nodded. "But let's back up so I'm not misunderstood. Let's first dismiss the ravings of the Flat Earth Creationists who doubt the world is even a globe, or even the strict biblical literalists who believe the planet is at best ten thousand years old. Let's jump ahead to the main arguments of those who advocate intelligent design."

Lisa shook her head. An ex-Nazi stumping for pseudoscience. What was going on?

Anna cleared her throat. "Admittedly, I will contend that most arguments for intelligent design are fallacious. Misinterpreting the Second Law of Thermodynamics, building statistical models that don't withstand review, misrepresenting radiometric dating of rocks. The list goes on and on. None of it valid, but it does throw up lots of misleading smoke."

Lisa nodded. It was one of the main reasons she had concern for the current drive to have pseudoscience presented alongside evolution in high school biology classes. It was a multidisciplinary quagmire that your average Ph.D. would have difficulty sorting through, let alone a high school student.

Anna, though, was not done with her side of the argument. "That all said, there is one concern proposed by the intelligent design camp that bears consideration."

"And what is that?"

"The randomness of mutations. Pure chance could not produce so many beneficial mutations over time. How many birth defects do you know that have produced beneficial changes?"

Lisa had heard that argument before. Life evolved too fast to be pure chance. She was not falling for it.

"Evolution is not pure chance," Lisa countered. "Natural selection, or environmental pressure, weeds out detrimental changes and only allows better-suited organisms to pass on their genes."

"Survival of the fittest?"

"Or fit enough. Changes don't have to be perfect. Just good enough to have an advantage. And over the vast scope of hundreds of millions of years, these small advantages or changes accumulate into the variety we see today."

"Over hundreds of millions of years? Granted, that is indeed a vast gulf of time, but does it still allow enough room for the full scope of evolutionary change? And what about those occasional spurts of evolution, where vast changes occurred rapidly?"

"I presume you're referring to the Cambrian explosion?" Lisa asked. It was one of the mainstays of intelligent design. The Cambrian Period encompassed a relatively short period of time. Fifteen million years. But during that time a vast explosion of new life appeared: sponges, snails, jellyfish, and trilobites. Seemingly out of the blue. Too fast a pace for antievolutionists.

"Nein. The fossil record has plenty of evidence that this 'sudden appearance' of invertebrates was not so sudden. There were abundant Precambrian sponges and wormlike metazoans. Even the diversity of shapes during this time could be justified by the appearance in the genetic code of Hox genes."

"Hox genes?"

"A set of four to six control genes appeared in the genetic code just prior to the Cambrian Period. They proved to be control switches for embryonic development, defining up and down, right and left, top and bottom, basic bodily form. Fruit flies, frogs, humans, all have the exact same Hox genes. You can snip a Hox gene from a fly, replace it into a frog's DNA, and it functions just fine. And as these genes are the fundamental master switches for embryonic development, it only takes minuscule changes in any of them to create massively new body shapes."

Though unsure where this was all leading, the depth of the woman's knowledge on the subject surprised Lisa. It rivaled her own. If Anna were a colleague at a conference, Lisa thought she might actually enjoy the debate. In fact, she kept having to remind herself to whom she was talking.

"So the rise of Hox genes just prior to the Cambrian Period might explain that dramatic explosion of forms. But," Anna countered, "Hox genes do not explain other moments of rapid—almost purposeful—evolution."

"Like what?" The discussion was becoming more interesting by the moment.

"Like the peppered moths. Are you familiar with the story?"

Lisa nodded. Now Anna was bringing up one of the mainstays on the other side of the camp. Peppered moths lived on birches and were speckled white, to blend in with the bark and avoid being eaten by birds. But when a coal plant opened in the Manchester region and blackened the trees with soot, the white moths found themselves exposed and easy targets for the birds. But in just a few generations, the population changed its predominant color to a solid black, to camouflage against the soot-covered trees.

"If mutations were random," Anna argued, "it seems amazingly lucky black showed up when it did. If it was purely a random event, then where were the red moths, the green moths, the purple ones? Or even the two-headed ones?"