Saturday, March 23, 2013

Faith, Facts, and Fossils

A Matter of Life and Death
In my family's religious subculture, judgments were frequently made about a person's eternal destiny (i.e., heaven or hell) based on that individual's affirmation of evolution or creationism. Our dear grandmother was known to accept evolutionary scientific theory and to enjoy PBS nature specials, therefore we besought God to change her heart and save her soul before it was too late.

As children, our reading material was closely monitored for Darwinian concepts which would be exposed as false and countered with the truth of "God's Word". We were indoctrinated with publications and videos from ICR and Answers in Genesis in addition to our science textbooks from A Beka, Bob Jones University Press, and Christian Light. The sciences never interested me as much as history and language arts, anyway; I only learned enough to get by.

When I began raising my own kids, though, I found that smugness was a poor substitute for understanding. My son loved to find picture books about dinosaurs and astronomy at the library and I felt intimidated by the pages that referred to "millions of years ago". I began to encounter references to evolutionary history in an assortment of unrelated contexts and my curiosity was piqued. I'd never actually learned what scientists meant by "evolution", only that it was factually and morally wrong. As a homeschooling parent, I felt obligated to clarify and fortify my own understanding of science so I could better direct my children's curiosity.

The Biblical Record
A closer look at Genesis revealed two distinct creation accounts. In the first, men and women are created together, on the sixth day in God's image to rule over the other creatures and everything is good. The earth is shapeless and empty; light appears, and darkness, and day and night (preceding the rest of the galaxy). Photosynthetic plants show up on the third day, the sun and moon are added the next day. Men and women (or man and woman?) are created at the end of the sixth day to be the dominant life form and they are specifically instructed to eat the plants. Everything is good, and God takes a break.

Chapter 2 offers an alternate version: there are no plants yet, and no rain. God molds a man out of the earth and breathes life into him to give him a soul. God plants a garden near some rivers and puts the man in charge of it. The man is permitted to eat from all the trees save one. But the man is too solitary and that's not good, so God sets out to make him a helper. He forms the ground, like play dough, into every kind of animal and every kind of bird, and sends the new creatures to Adam to see what he will call them. When none of them prove satisfactory, God puts Adam to sleep and surgically removes a rib which he shapes into a woman. Adam is thrilled when he wakes up--since neither of them have heard of clothes--but "the woman" goes unnamed until the end of the next chapter when she starts bearing children.

For centuries, intelligent men attempted to organize the Bible's many stories (Creation, Noah's Flood, Abraham, the Exodus, the Promised Land...) into a workable historic timeline. One of those men was James Ussher, Archbishop of Ireland, who in the days of Oliver Cromwell's Commonwealth coordinated the biblical accounts with the best known history of other cultures to determine that the world must have been created in 4004 B.C. As scholarship advanced through the Enlightment and beyond, scientists (many of them Christians) began to talk about the age of the earth in much longer terms, and many in the Church kept pace with these new discoveries. At the same time, however, Ussher's calculations were printed in the King James Version as standard reference notes, where they remained for 200 years and eventually featured in America's Scopes Trial of 1925, a defining moment for  fundamentalist Christianity.

Christianity and Evolution
I first heard Dr. Francis Collins on NPR. A Bible-believing Christian who accepted evolution? I had to learn more. His book The Language of God opened a new world to me. Real scientists, he explained, are "anarchists", always seeking to revise theories and overthrow old research. One of the great revisions of the last century was the conclusion that the universe began at a single moment (14 billion years ago). To Dr. Collins, "The Big Bang cries out for a divine explanation."

Dr. Collins writes frankly, kindly, and convincingly. He patiently answers the common creationist arguments ("the watchmaker", entropy, fossils) while pointing out that three types of radioactive carbon dating yield concordant results: 4.5 billion years for Earth's oldest rocks. He summarizes current scientific understanding about the descent of Homo sapiens. And as the director of the Human Genome Project, he includes some information that was most definitely not in the materials from Answers in Genesis or ICR twenty years ago.

As it happens, humans have 46 chromosomes while chimpanzees, bonobos and gorillas have 48. Interestingly, the second human chromosome has the appearance of being fused (parts midway in the chromosome resemble what are usually the telomeres, or ends) and the genes on that chromosome share the order of the genes in two smaller ape chromosomes (2A and 2B). Denisovan hominids had the same fusion we have, suggesting this change in chromosome number occurred previous to the first human. Scientific genetic evidence now strongly indicates a fusion of those two chromosomes took place a million years ago or even more. A rare mutation would later have reduced the number from 47 chromosomes to 46. Human life is no less amazing for having evolved--if anything, the wonder seems greater! I had to keep reading.

"You cannot get to Young Earth Creationism without throwing out the fundamental principles of geology, of biology, of chemistry, of physics, of cosmology, of paleontology."  
               --Francis Collins

  "No serious biologist today doubts the theory of evolution to explain the marvelous complexity and diversity of life."   --Francis Collins

Scientific Evidence
In A Natural History of Time, geophysicist and researcher Pascal Richet traces mankind's attempts to determine the age of the earth, our solar system, and the universe. Beginning with mythology, religion, and philosophy and culminating in geology, astronomy, physics, and the discovery of radioactivity, the curious kept imagining, exploring, calculating, and reaching ever closer to an accurate chronology. Richet brings the names to life: from Aristotle to Isaac Newton, from Lord Kelvin to Percival Lowell. This book took me months to get through, but by the time I reached the end I was cheering each new scientific discovery and was convinced that our planet really did form 4.5 billion years ago.

Even if one does not accept that fossils can be dated by their location in the rock strata, there is the inescapable issue of "missing links". I was taught that there were none, that the fossilized skeletons we find today are simply extinct species, or variations of the same species that exist on earth today. Turns out there are plenty of transitional forms in the fossil record: a manatee with legs, serpent-like whales with tiny feet, walking whales, the Tiktaalik fish, the Dimetrodon which looked like a dinosaur but wasn't, toothed birds, a flatfish with an intermediate eye position, the early bipedal dinosaur Eoraptor, the mammal-like reptile Thrinaxodon, and so on.

Additionally, there is the beautiful and predictable sequence of life forms, from most simple to most complex, that unfolds through the rock strata. Mammalian fossils are not found in the oldest rocks, nor are flowering plants. The sheer number of fossils is staggering. If all fossils were formed during a single flood, the pre-flood oceans would have been crowded with an unsustainable number of creatures! Fossils remind us that humans have not always been Earth's dominant species. We are only the latest on the scene, at the top of an ancient and elaborate tree.

Ken Ham and other evangelical creationists have been emphatic in their interpretation that there was no death until after "the Fall". Nothing died until the woman first disobeyed God. Therefore, Adam and Eve and all the first animals, fish, birds, and insects were originally created to be vegetarian. The ignorance of this simplistic explanation came to mind when I took my first college course in biology and realized that plant cells are every bit as alive as blood cells. Life and death are so much more complex than eating forbidden fruit and suddenly beginning to age.

Facts and Faith
I gradually embraced evolution--not as a "worldview" that allowed me to do what I want, but as an evidence-based way of understanding the world I live in. Which is probably why the following blog post by Libby Anne resonated so strongly with me last year:

"If my parents had not elevated creationism to the same importance as the virgin birth, I would never have had my crisis of faith. Doing so gave my faith an Achilles heel. I’m not saying this happens to everyone raised to equate creationism with Christianity – it doesn't. What I am saying is that elevating things like capitalism and spanking to the same level of truth as the trinity creates a Christianity in a box. It shuts off questions and exploration. It closes the door to differences of opinion. It creates a situation where you are either in, or out. And, more importantly, it creates a situation where questioning something as simple as capitalism means rejection and changing your mind on something as little as anti-gay rights means potentially throwing everything from the trinity to the divinity of Jesus into question."
"My parents reacted negatively to me not because I had rejected Jesus but because I had rejected creationism."    --How Creationism Drove Me Out of the Church

Young earth creationism no longer makes sense to me. The universe is too immense to be contained in 6,000 years of history. Starlight finds us from millions of light years away. Fossils give us clues to secrets that are millions of years old. Rocks bear silent testimony to billions of years of atomic energy. Antarctic glaciers record over 8 million years of history in their frozen hearts. Life is a mystery, a puzzle to tease out bit by bit, each of us adding to the random but intricate and kaleidoscopic pattern that will cause future generations to marvel.

1 comment:

  1. I just came across your excellent article.

    One small technical detail. From your discussion of Francis Collins' book you say "...three types of radioactive carbon dating yield concordant results: 4.5 billion years for Earth's oldest rocks". That doesn't seem right.

    Dating from carbon (decay of the C14 isotope) is only reliable back to about 50,000 years. This is very, very recent in geological terms. Dating of older materials uses decay of isotopes of other elements, not carbon, that have much longer half-lives. I suspect that Collins wasn't talking about carbon if his context was the age of the earth, some 4,500,000,000 years.

    (To a very, very rough approximation, radioactive dating from a given isotope can only be done to about eight or nine times its half-life. C14's half-life is about 5,730 years, so its usefulness for dating goes back about a mere 50,000 years.)

    So rather than "three types of radioactive carbon dating...", what Collins probably said was a carbon-free "three types of radioactive dating...".

    Could you check this, please? Do you have the page number from Collins' book?