The driver of modern alchemy.

So, What Really Drives Origin-of-Life Research?

Denyse O'Leary

 

 

Whether a field is considered "science" or "pseudoscience" now often depends principally on its relationship to naturalist ideology, not on whether it advances our understanding. What exactly have speculations about the multiverse contributed to science, for example? Today, in fact, evidence-based and reality-based thinking are seen not as tools or guides but as obstacles to the quest to make the multiverse real, at least in our minds -- possibly the only place it ever can be real.

Origin-of-life research provides another classic illustration. Our survey of the field has turned up crowds of conflicting theories churning a largely disputed fact base. Crowds of conflicting theories is a bad sign in itself; when a science is advancing our knowledge, disagreements becomes sharper perhaps, but narrower. OOL research offers occasional new understandings here and there -- and so did the practice of alchemy. That is because, happily, we can often learn something even when on the wrong track. But until we are on the right track, we cannot develop a large, organized program of evidence-based knowledge.

Sometimes, we refuse to admit we are on the wrong track because of a heavy emotional investment. Just such an investment drives current OOL research: the need to disprove design. As cosmologist Paul Davies explains,

Many investigators feel uneasy about stating in public that the origin of life is a mystery, even though behind closed doors they freely admit that they are baffled. There seems to be two reasons for their unease. Firstly, they feel it opens the door to religious fundamentalists and their god-of-the-gaps pseudo-explanations. Secondly, they worry that a frank admission of ignorance will undermine funding, especially for the search for life in space.¹

Well, continuing failure can undermine funding too.

The alchemists slowly began to change their goals: They began to meet nature on her own terms. What they then learned about the elements and their real interrelationships proved far more valuable than what they had given up, though the nature of their choice prevented any such prior knowledge.

What if origin-of-life researchers did something similar? Quit looking for the hidden law or the magic zap. If it is design, fine, how does the design work? For the record, there can be design without creation. Philosopher of science Del Ratzsch offers,

For instance, suppose that we finally discover that life can arise spontaneously but only under exactly one set of conditions. One must begin with 4003.6 gallons of eight specific, absolutely pure chemicals, exactly proportioned down to the molecule. The mixture must then be sealed into a large, light green Tupperware container with one sterile copy of Sergeant Pepper's Lonely Hearts Club Band. Do that, and life develops spontaneously by natural means (catalyzed by the precise surface characteristics of "Sgt. Pepper"). Its development, subsequent reproductions and characteristics are completely according to normal natural laws. And life in this case was not directly specially created. But those initial conditions involve interjection of deliberate intent and design with a vengeance.²

For now, life goes on. A decade ago, Harvard University announced that it was spending a million dollars annually to find the origin of life. Their hope was succinctly expressed by Harvard chemist David Liu, "that we will be able to reduce this to a very simple series of logical events."

Carl Woese and Gunter Wachterhauser have been more realistic and less sanguine:

In one sense the origin of life problem today remains what it was in the time of Darwin -- one of the great unsolved riddles of science. Yet we have made progress. Through theoretical scrutiny and experimental effort since the nineteen-twenties many of the early naive assumptions have fallen or are falling aside -- and there now exist alternative theories. In short, while we do not have a solution, we now have an inkling of the magnitude of the problem.

And Stanley Miller, of the Miller-Urey experiment? He too has gone on record saying, "Origin of life has turned out to be much more difficult than I, and most other people, envisioned." with science writer Dennis Horgan adding in 2011, "Pssst! Don't tell the creationists, but scientists don't have a clue how life began." These are the kinds of things people say when they have spent a great deal of time, energy, and money with no discernible result. It is depressing indeed if a major concern is, "What will the creationists say?"

Some advocate a complete rethink. Others offer more guesses. Still others, mindful of their heritage, inform us that "Charles Darwin Really Did Have Advanced Ideas About the Origin of Life." As if anyone should care much at this point whether a man who was prudent enough to step around the mess ages ago had advanced ideas about it or not.

If all the mutually contradictory, sketchily supported theses offered over the last 150 years are naturalism's best efforts, then surely this is the most reasonable conclusion: There is no convincing, perhaps no believable, scientifc evidence for a merely natural origin of life. Can information theory help us here, as it can with evidence-based cosmology?

References:

(1) Paul Davies, The Origin of Life (London: Penguin Books, 2003), p. xxiv.

(2) Del Ratzsch, "Design, Chance & Theistic Evolution," in William A. Dembski, ed., Mere Creation: Science, Faith & Intelligent Design (Downers Grove IL: InterVarsity Press, 1998), p. 291

 

More storytelling.

Did life begin on Mars and then travel to Earth for its blossoming?

A long-debated and often-dismissed theory known as "panspermia" got new life in the past week, as two scientists separately proposed that early Earth lacked some chemicals essential to forming life, while early Mars likely had them.

First came Steven Benner, an iconoclastic and highly regarded origins-of-life chemist with the Westheimer Institute of Science and Technology in Gainesville, Florida.

Last week, during a keynote talk at the Goldschmidt conference for geochemists in Florence, Italy, Benner said that two elements that allow the precursors of life to form were almost certainly unavailable on early Earth but were likely present on early Mars.

"Basically, we went looking on Mars because the origins-of-life options on Earth just aren't looking very good," Benner said.

One of the stumbling blocks to life starting on Earth is the fact that water is almost universally accepted as necessary for the onset of life. Yet RNA—which many consider to be the earliest expression of genetic replication and another essential precursor to life as we know it—falls apart if you try to build it in water.

What keeps that from happening, Benner has found over years of study, is the presence of a form of the element boron. While geologists say boron was too scarce on early Earth to support any widespread creation of RNA, it was seemingly more abundant on early Mars. One sign of its presence on the red planet is that at least one meteorite has delivered some Martian boron to Earth.

Benner has also found in his lab that if a form of the element molybdenum is added to the mix, the boron-steadied compounds are rearranged to form a stable version of ribose—the "R" in RNA.

Again, the element was far more available on early Mars than early Earth. (See "Naked Science: Finding the Origin of Life.")

So the question arises: Did RNA on Mars lead to actual DNA-based life? And did those lifeforms then travel to Earth on rocks kicked up when a meteorite struck Mars?

"The Phosphate Problem"

A few days after Benner's talk on August 29, a paper appeared in the journal Nature Geoscience that made a similar argument about phosphorus compounds, which form the backbone of RNA, DNA, and proteins.

While phosphates were present on early Earth, said lead author Christopher Adcock of the University of Nevada, Las Vegas, they were most frequently found in a solid state, in which they are most stable. Yet biology is understood to have started in water, which would have contained little of the phosphates on early Earth.

"This has long been called 'the phosphate problem,'" Adcock said in an interview. "There are theories out there about how it might have worked [on early Earth], but there's no consensus.

"That played a part in getting us interested in Mars," he said.

On Mars, Adcock's team concluded, the phosphate problem appears to be much smaller. Adcock and his colleague Elizabeth Hausrath synthesized the two types of phosphates known to be on both early and current-day Mars, compounds that have also been delivered to Earth via meteorites.

Those Martian phosphates turned out to be far more soluble in water and also more abundant. So when it came to essential phosphates, at least, Mars appears to have been a better nursery for life.

Answering the Big Cosmic Question

The reemergence of the theory of panspermia is intertwined with progress (or lack of progress) in a long-term scientific quest to find out how life began on Earth, a question that synthetic biology experts such as Benner have been working on for decades. Despite some advances, the field has come up against chemical walls that are proving impossible to climb.

For instance, Benner said, the organic—meaning carbon-based—compounds understood to have come together to form life in a "prebiotic soup" do not behave in the lab in a way that would indicate they led to the formation of life on early Earth.

When these compounds are energized by heat or light, instead of producing early RNA they create tar—hardly the stuff from which we would all evolve. Yet discoveries over the past decade on Mars have pointed to a planet that was once warmer and wetter than it is now.

No living or fossil organisms have been found on Mars. But the science team working with the rover Curiosity concluded earlier this year that they had drilled into an ancient lake bed that had all that was needed to support life—and consequently that the planet had been habitable. (See "NASA's Mars Rover Makes Successful First Drill.")

That doesn't mean it ever was inhabited, but scientific signs are beginning to point, however hesitantly, in that direction.

Does this mean Benner or Adcock sees panspermia as a likely beginning for life on Earth? Not exactly.

Benner says that "it's yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite." But it's more of a changing of probabilities than it is scientific proof.

"A panspermia solution, after all, produces another panspermia problem," he said. "If a Martian microbe did make it from Mars to Earth, maybe it would be as if it landed in Eden. But just as likely, it would quickly die."