What is the Origin of Life?
Meyer: Well, I got interested in the debate about the origin of life in a kind of odd way. There was a conference that came to the city where I was working that was examining that topic. And I was shocked when I attended the conference to find there were leading figures in the field who were all essentially acknowledging that we had no evolutionary account of the origin of the first life. I thought that the evolutionary biologists had this all sewn up, but it wasn’t the case. And one of the scientists on that panel was a man named Charles Thaxton, who was living in Dallas, where I was living at the time. He’d just written a book called The Mystery of Life’s Origin in which he had provided a really comprehensive critique of what was called chemical evolutionary theory, the attempt to explain the origin of the first life from simple non-living chemicals. And he made the case, and the other scientists from various persuasions on the panel agreed, that we didn’t have an explanation for this. And it was a question that Darwin didn’t address in 1859 and it really hadn’t been solved in the ensuing years. So I got fascinated with that, and a year later when I went off to graduate school, to England, I began to study that question, the origin of the first life.
Ankerberg: Alright, now, we’ve got Darwin’s tree of life up here. And explain, you just said that Darwin didn’t have an answer for this thing. Talk about this tree of life.
Meyer: Well, the tree of life was his famous depiction of the history of life. The vertical axis shows the passage of time and the horizontal axis is all the new form that arises over time. So if you look at the branches at the end of the tree, they represent all of the forms of life that are on the planet today. And the idea in Darwin’s theory is that new forms of life arise by a gradual evolutionary process that converts simpler preexisting forms into those complex forms we see today. The simplest form, where the whole process starts, is represented by the trunk at the base of the tree. And Darwin didn’t address the origin of the trunk, where we got the first life at the very beginning. And oddly, though there have been attempts to explain that since his time, 150 years on we don’t have any undirected evolutionary theory of the origin of life that is satisfying the scientific community.
Ankerberg: Yeah. Down there at the bottom of the trunk…
Meyer: It’s a mystery.
Ankerberg: …you had a mystery. And they used to say there was a prebiotic soup, and now there is no prebiotic soup, you’ve discovered that. The fact is the idea going at that time was there was some kind of soup, and the cell wasn’t that tough a deal to unscramble. What did Huxley say about the cell way back then?
Meyer: Well. Exactly. In the 19th century, when Darwin first proposed his theory, it was fairly quickly accepted by a lot of scientists. There was debate, but eventually a consensus arose that Darwin had refuted the design argument. He’d shown that there was no evidence of actual design in nature, only the appearance of design. And yet, there was a question that he never resolved, which was: How do you get life going in the first place? But scientists who were of the Darwinian perspective or persuasion didn’t worry too much about that, because they thought the cell was simple and it was inevitable that we would be able to explain it in the same kind of way involving purely undirected processes. And Huxley put it in a colorful way. He said that the cell is a “homogeneous glob of undifferentiated protoplasm.” It’s like Jell-o or something, some goo.
Ankerberg: But it didn’t stay that way long. In other words, as science marched on, you got tools to better investigate the cell. And Oparin came up with a theory for some of the new discoveries at that time. Explain his theory.
Meyer: Well, maybe the first thing to say is that, that each time science discovered that there was more complexity involved in life than they thought, that the cell was a lot more complicated than they realized, then their ideas, scientists’ evolutionary ideas about the origin of life, had to keep pace with that. So, scientists had to come up with an account of that. And the first one to do that was a man named Alexander Oparin, who developed what was called a chemical evolutionary theory, or sometimes called evolutionary abiogenesis – life from non-life.
Meyer: And he envisioned not a one or two step process, which is what Huxley and others were thinking about in Darwin’s time, he envisioned a seven or eight step process where you started from very simple chemicals that combined and recombined as various energy sources were supplied, and then they eventually produced the proteins that we knew about. And then after that there was a cell, an enclosure that was wrapped around those proteins, and voila, that would be the first life. But what Oparin didn’t initially know about was the structure and complexity of DNA. It was really the discoveries that were being made in the 1950s by Watson and Crick and other scientists working on proteins. Watson and Crick studied DNA, other scientists studied proteins, and the more we learned, the more implausible this simple step-by-step evolutionary process began to seem.
Ankerberg: When they finally got down to DNA, what was the big mystery that your book is all about?
Meyer: Well, there’s two mysteries. And Watson and Crick solved the first one, which was the structure of the DNA molecule itself and, I would say, associated with that is what it does. On the screen you see the beautiful DNA double helix, with the chemical subunits that make up the molecule highlighted on the right. And there you see that there are some special chemicals that have little letters on them, and they’re called in chemical parlance, bases or nucleotide bases. And in 1953, Watson and Crick discovered the structure of the DNA molecule. But four years later, Crick had an incredible insight. I think it was a breakthrough insight in the whole history of biology. And it was formulated as a hypothesis that was subsequently confirmed by later discoveries, and it was called the sequence hypothesis. And his idea, which turned out to be correct, is that those four chemicals, called bases, function exactly like alphabetic letters in a written text, or digital characters, zeros and ones, in a machine code or a section of software. It’s the specific arrangement of those bases that allow them to perform a communication function in the cell. They literally, the arrangement of those characters, literally conveys information that allows the cell to build all the important proteins and protein machines that it needs to stay alive.