As Nigel Goldenfeld and Carl Woese describe it, we have an understanding of the framework for the origins of life on Earth.
At first, pieces of the puzzle interacted with their environment in the primordial soup and with each other. They actively swapped materials, innovations and tools, testing different combinations until a "tipping point" was reached and new, optimized forms emerged, at which point the process jumped to a higher level.
On and on this went until these precursors could translate nucleic acid sequences, basic stuff of life at that point, into protein sequences, basic stuff of life as we know it now.
Woese, the University of Illinois' internationally heralded microbiologist, has compared it to the human development of language and the possibilities opened by the ability to express things symbolically. In effect, the more primitive code of nucleic acids was translated into a new alphabet of amino acids, forming the protein words that made up the marching orders for evolution.
"Translation" set these pre-cells apart, solidifying their forms, letting them become cells as we conceive of cells and capable of evolving vertically – into more advanced forms of life – in the Darwinian sense.
But knowing how the process appears to have worked in a broad sense is different than understanding it in detail – how the parts worked together and why they resulted in the key mechanism of translation.
Goldenfeld, a UI physics professor, likens it to breaking apart a watch, studying its components and even learning how they fit together but still not knowing how it is they function to tell time.
"There's still a big gap between knowing something can happen and knowing really how it happens in detail," he said recently. "We understand (life's origins) in general terms, but we don't understand the specifics."
Goldenfeld, Woese and UI chemistry Professor Zaida Luthey-Schulten are taking a lead role in closing that gap in understanding.
Goldenfeld and Woese are among the principal investigators in a $5 million, five-year National Science Foundation program to pin down how life emerged on Earth. While the project is headed by the Santa Fe Institute, which oversees multidisciplinary collaborations in the physical, biological, computational and social sciences, and Harold Morowitz, a biology and natural philosophy professor at George Mason University, a significant part of the work will be done at the UI.
Luthey-Schulten, whose lab specializes in computer simulation of complex biological processes, also is part of the project, and all three UI professors are principal investigators on a $900,000, three-year Department of Energy grant to study how translation in cells emerged and evolved into life's genetic code.
In effect, the Energy Department study takes up where the National Science Foundation study leaves off, Goldenfeld said. In both cases, the researchers are working through the UI's new Institute for Genomic Biology, at which Goldenfeld leads a research program in biocomplexity.
Goldenfeld said the Energy Department is interested because much of the work focuses on microbes, which make up more than half the biomass on Earth and thus are integral to understanding how to control and repair ecosystems.
Woese, winner of the Crafoord Prize, the equivalent of a Nobel in microbiology, said he views understanding translation as understanding biology itself. But the subject was largely shunted through the 20th century as scientists concentrated on genes, he said.
Woese likened it to studying the building blocks of life while mostly ignoring the machine – one of the most complicated in biology – that produces those building blocks and the how and why of its origins and form.
He said he sees the two projects as not so much about understanding the particular result of evolution – life – as understanding how evolution itself works.
"We do care about the end result," Goldenfeld said. "But it's not as though we're interested in one particular organism. We're interested in the common features of life ... the common principles that govern the way all of the organisms function."
Goldenfeld said Woese's research is an inspiration for both projects.
Woese added a third branch of life – archaea, microorganisms that thrive primarily in extremely harsh environments – to the evolutionary picture in the 1970s. Then, three years ago, he proposed a major revision in the theory of evolution, positing that life didn't begin with one primordial cell but with a large number of loosely organized sort of precells, which interacted horizontally in an ongoing process eventually yielding translation.
Woese decided he needed help in understanding how interactions among basic components could produce something with the complexity of life. That led him to Goldenfeld, one of the UI's cadre of world-class condensed-matter physicists, who study how interactions among tiny particles, atoms and electrons, for example, give rise to complex properties of matter like superconduction.
Goldenfeld already was working with the UI geology department, and microbiology Professor Bruce Fouke was looking at how microbes play into the formation of the intricate landscapes in hot spring environments like Yellowstone. He had even taught a course in biocomplexity to enhance his command of the subject.
"He (Woese) was looking for a physicist, and I was a physicist wanting to work in biology," Goldenfeld said.