Steen Rasmussen: The Flag Bearer Of Artificial Life
Steen Rasmussen: The Flag Bearer Of Artificial Life
By Suzan Mazur
December 7, 2012
"[W]e as humans are naive if we believe that we are the end product of evolution. I'm sure we are not." -- Steen Rasmussen
Hal (2001)? Roy (Blade Runner)? Terminator? Dinosaurs of Jurassic Park? Danish physicist Steen Rasmussen thinks seriously about sci-fi scenarios most of us see as Hollywood entertainment. But then Rasmussen is the flag bearer of Artificial Life and was one of the founders of the AL movement in the 1980s, also organizing the first two international protocell conferences in 2003. His first laboratory? A farm in Denmark "chasing cows" as a kid, thinking about the stars, drawing and dreaming…
At Los Alamos National Laboratory where he spent two decades as a physicist, Rasmussen also flirted with acting, once portraying the late Robert Oppenheimer in a comedy about how the atomic bomb would be impossible to make there today because of excessive security and red tape. He has dabbled a bit more in theater since his return to Denmark five years ago -- where he now heads the Center for Fundamental Living Technology at the University of Southern Denmark (SDU)-- the return to Denmark due to the availability of basic research funds not dramatic roles.
Rasmussen is fascinated by a technological future with "democratized material production," i.e., an at-home personal fabricator to spin out medicine, electronics, clothing, "anything." Perhaps more importantly, he sees us inventing machines that can "love more deeply" than may be humanly possible.
He thought a decade ago we'd by now have developed protocells, but insists we are "very close" indeed to synthesizing one.
"For large parts of my life I may have been working 70-80 hours a week," says Rasmussen with a certain laugh signaling that science is also great fun.
If you're thinking Alec Guinness, Man in the White Suit, the ex-Cambridge scientist who succeeds in cooking up a fiber that never gets dirty -- well, yes, Rasmussen admits the recipe does require a pinch of obsession.
Aside from his above-mentioned role at SDU, Rasmussen is Principal Investigator for Denmark's Initiative for Society and Policy (based at >SDU), whose mission is to give science-based knowledge more visibility in the public discourse "to counterbalance the ideologies."
He continues a quarter-century long affiliation with Santa Fe Institute, now serving as External Research Professor following 16 years as Researcher in Residence.
Rasmussen's career began at Los Alamos, first as a postdoc in the 1980s, then as Team Leader for Self-Organizing Systems, and head of the Protocell Assembly project. He was co-director of Europe's Programmable Artificial Cell Evolution project (PACE), Principal Investigator for "Cell-Like Entities" sponsored by the US Air Force (2004-2005), and co-Principal Investigator for "Water on Mars" at Los Alamos (2003-2005).
He co-developed the Transportation Simulation System (TRANSIMS), which the US Department of Transportation later implemented. Rasmussen also developed an integrated simulation framework for urban systems and web-based disaster mitigation tools once used to reconnect 20,000 people who had been evacuated, tools also employed following 9-11.
Steen Rasmussen is the author of hundreds of scientific papers and presentations, and co-editor of the first book on protocells, with M. Bedau, L. Chen, D. Deamer, D. Krakauer, N. Packard and P. Stadler, Protocells: Transitions from nonliving to living matter(MIT Press).
He was also featured in the PBS Nova program "Life From Dust" and is a frequent public lecturer.
Among his many scientific honors are: P. Gorm-Petersens Mindelegat (awarded in the presence of Queen Magrethe II of Denmark); Los Alamos Cerro Grande Wildire Award (2000); Los Alamos Achievement Award for Excellence: Protocell design, and for Simulation of Critical Infrastructures (2004); World Technology Network Award, Biotechnology Category: Protocell design.
Rasmussen has an M.Sc. degree in Physics and Physical Chemistry, and a PhD in Physics, both from the Technical University of Denmark.
He says he is happy to be back home in Denmark and values the basic research opportunities Europe now provides, but that he really misses the spirit and openness of America's Southwest (also, the convenience of US 24-hour service and shopping). My interview with Steen Rasmussen follows.
Suzan Mazur: In researching an appropriate image for this story I was struck by the fact that at some point you may have had to choose between the stage and the lab. Have you ever had an interest in acting?
Steen Rasmussen: No, that's not true. I could have gone into the visual arts though. Also, when I was younger I was asked if I was interested in modeling, which I flatly refused to do. But in retrospect, that could have been fun. My daughters are now models and my oldest is an actress as well.
I did a bit of acting when I returned to Denmark, a local production the art department at the university organized. A play about eternal life and robotics.
Also, I was Robert Oppenheimer in a play at Los Alamos many years back. That was a comedy about how it would have been impossible to make the atomic bomb at Los Alamos today with all the security regulations and nonsense administrative procedures currently in place.
My family thought I'd become an artist or an architect because drawing felt so natural for me.
Suzan Mazur: Do you come from a science family?
Steen Rasmussen: No, my dad was a farmer, my mom a homemaker. I grew up in the country. I was chasing cows and digging ditches and participating in the harvest. My dad was also a contractor. He built houses. I come out of a craftsman and farming tradition.
Suzan Mazur: Your interest in science comes from where?
Steen Rasmussen: My parents were just very supportive of these odd things I was interested in. Some of the early experiences I remember are my dad taking me out at night to look at the stars. We'd talk about infinity and about how far away the stars are. He'd tease me, asking whether I thought the Universe would end and whether there was a wall. And if there was a wall, what was behind the wall. My mom would tell him to stop teasing me. So from the time I was a little kid sitting on my dad's shoulders looking at the stars, I've been interested in these questions.
Suzan Mazur: Also, Denmark is a wonderful science lab in the green, warm months.
Steen Rasmussen: Yes, when we have a good summer. The Danish summer can be gorgeous. There's light most of the night and it's warm enough to go swimming in the sea. We have many folk songs that praise the Danish summer. But the Danish summer is also said in folk songs to be this unfaithful beautiful woman who plays with you and then disappears, and you just get rain and cold weather after that.
You should be glad you're not here right now. The weather's terrible in the winter, grey, dark, wet and depressing. I wish it were snowing. I lived for 20 years in New Mexico and love it there. It's my other home, which I miss when I'm here.
Suzan Mazur: So why exactly did you leave New Mexico and the US and return to Denmark? And do you see a US - European rivalry regarding Origin of Life/protocell research?
Steen Rasmussen: Until recently, and since World War II, the US has invested significantly more than Europe has in all aspects of scientific research and development. That was why it was clear to me as a postdoc some 25 plus years ago that I needed to go to the US to develop my scientific career.
However, this US - European balance has shifted rather dramatically over the last 20 years, at least within my area. Today, I believe we have passed a tipping point where there is more basic funding available in Europe than in the US. Europe's young scientists don't have to leave for the US to pursue a career.
This shift was caused in part by the vision and implementation of new funding initiatives within the European Commission (Future Emergent Technology program) and the Danish National Science Foundation (Basic Science) and partly due to a significant decrease in basic research, i.e., curiosity research funding across the board within the US. This was clearly felt at Los Alamos National Laboratory after the end of the Cold War. It was this shift in the availability of basic research funding that made me return to Europe. It was not because I wanted to leave the US.
Today I don't believe there is a will to spend public funds for Origin of Life research on either side of the Atlantic. However, we do see cultural differences between science in the US and in Europe. Basic research is more an integral part of the scientific culture in Europe than in the US. In contrast, the utility aspect of what you do as a scientist is clearer in the US than in Europe.
In any event, it is very difficult to obtain funding to do blue sky Origin of Life research, e.g., to develop protocells in either the US or Europe. However, scientists can address some of the Origin of Life questions within a context of bottom-up synthetic biology, self-replicating and repairing materials or living technology.
NASA as a funding agency in the US is an exception, as they actually have language in their research calls to support Origin of Life research. However, those funds are so minute that they are mostly symbolic in value, although I do see excellent work both by NASA postdocs and their Astrobiology Initiatives. NASA was created to fly and it is the science that supports space exploration that gets priority, not Origin of Life research.
I think the better strategy now is to seek Origin of Life funding from private US philanthropy rather than from NASA.
Suzan Mazur: You've been developing a protocell for about a decade. What is a protocell, that is, how do you define life, how close to making the protocell are you, and why are you doing it?
You made a statement about a decade ago:
"By assembling one possible bridge between nonliving and living matter we hope to provide a brick in the ancient puzzle about who we are and from where we come."
Is this still your thinking?
Steen Rasmussen: Yes. It is.
Suzan Mazur: What is a protocell and how do you define life?
Steen Rasmussen: A protocell is a physical-chemical implementation of the simplest life form that we can either make or that can emerge spontaneously. I think there are many different ways we can make minimal living systems. Just to be clear, I'm speaking about the transition from nonliving to living materials, where you start out with components that are nonbiological.
They can be organic or inorganic materials or both. If you put them together in a particular way, you can create a system that can take in resources and convert those resources into building blocks for the system to grow and divide. Then if you have information, some kind of guidance for how this division process happens that is inheritable, and if the inheritable information can change from one generation to the next, then you have the possibility for selection. Because one kind of information control of how you grow and divide may turn out to be better than another information control of how you grow and divide, the better one will be selected and reproduce. As this process continues you have evolution, and then you're done. If you can implement a system that can do this, you have created a minimal cell.
The game, of course, is: How simplistically can that be done? A modern cell is a really complicated machine, but many of us think life can be created in much, much simpler forms.
Life for me is a physical process. In principle, living processes can be carried by different kinds of materials. You are not limited to biochemistry. In our laboratory, in experiments we did at both Los Alamos and here in Denmark, we were not using biological materials. We're using molecules that do not exist in modern biology. We're really building out of something that's different than what modern biology is using.
Again, in principle, you could build living systems out of robotics parts. We are not doing that, other research groups are pursuing that. But I think it's completely conceivable to have a macroscopic system that's able to build copies of itself.
Suzan Mazur: Why are you not working with biological material?
Steen Rasmussen: Life is a much more general process than what we see in modern biology. You can have living processes carried by robotic systems, by computational systems and by mixtures of biological, robotics and computational systems.
Suzan Mazur: I saw a reference to your definition of life and your colleagues’ definition of life: The ability to evolve, self-reproduce, metabolize, adapt and die. Does that still hold?
Steen Rasmussen: Yes. But to further address why we are not working with biological material, remember that modern biology has evolved over billions of years and has presumably developed sophisticated ways to solve the problems of being alive. I think there are simpler ways of doing that, maybe similar to the ways in which life emerged. We're trying to find such simpler ways.
If you want to create life more simplistically than modern life is doing it, you can't use the sophisticated solutions modern life has evolved. It means you end up constructing your own building blocks. You have to build systems that are based on much simpler components. You actually need to have some of these components to carry more than one functionality.
For example, if you look at how the genetics in modern biology, the information and the metabolism interact with each other, it's a really complicated network of reactions and feedbacks.
To obtain the same functionality we have developed a very simple way, where the informational molecules, what corresponds to modern DNA, interact in a simple chemical way with the metabolism. There's a direct coupling so that electrons are jumping back and forth between the metabolic molecule and the informational molecule, which does not happen in modern life.
Suzan Mazur: How many labs worldwide would you say are now working on protocell development and which are the key labs?
Steen Rasmussen: It's difficult to say.
Suzan Mazur: I saw a figure of about 100.
Steen Rasmussen: I think there are more than 100, if the goal is working on different aspects of a protocell.
A few years ago, David Deamer from UC-Santa Cruz, the grand master of this kind of chemistry, went to the trouble of investigating how many labs there are, identifying nearly 100. I believe there are many more labs today due to increased interest in synthetic biology, artificial life and related fields. However, there are still not that many labs focused primarily on protocell development, if you look closely at their websites.
Suzan Mazur: You listed various research groups on your ProtoCell page:
Los Alamos Protocell
PACE (Programmable Artificial Cell Evolution)
ECLT (European Center for Living Technology)
ECCell (Electronic Chemical Cell)
MATCHIT (Matrix for Chemical IT)
MICREAgents (Microscopic Chemically Reactive Electronic Agents)
The Ribozyme Lipid Artificial Cell Initiative and COST-1
The Ribozyme Lipid Artificial Cell Initiative and Szostak's Minimal Cell
Minimal Living Cell
Steen Rasmussen: That website is no longer up to date. Many of these are projects I have been directly involved with or have some direct knowledge about. I'd say worldwide there are still less than 35 labs where they would say on their website: Yes, it’s part of our job to develop a protocell.
Suzan Mazur: Is PACE still ongoing?
Steen Rasmussen: PACE is an example of one of these European-sponsored projects. We concluded that in 2008.
Suzan Mazur: PACE was working with a computing center in Barcelona?
Steen Rasmussen: Yes. That's right, Ricard Sole' from Barcelona was part of PACE, but PACE was directed by John McCaskill in Germany.
Suzan Mazur: PACE's collaboration with the Barcelona computing center reminds me a little of what the Origin of Life group meeting at CERN may be proposing to do. You'll be participating at the CERN meeting?
Steen Rasmussen: I was invited to the preliminary brainstorming meeting at CERN in 2011 by Stu Kauffman.
[Note: The 2013 Origin of Life strategic meeting participants have not yet been officially announced.]
It's wonderful that CERN is hosting the Origin of Life question. CERN is used to organizing large-scale collaborative science teams, which solving the Origin of Life puzzle requires.
It's no surprise that it was Stuart Kauffman, an old friend and colleague of mine at the Santa Fe Institute, who instigated this idea. Stu is one of the biggest and best dreamers I know. He has always been fascinated with Origin of Life and throughout his career has provided vision and inspiration across disciplines.
How life originated on our planet is one way of thinking about this problem. But the problem really has two aspects. First, the historical aspect, for which we have no idea. We can't go back in time and see what happened. Second is the more scientific aspect, which has to do with properties of matter. I'm much more interested in this second aspect. I'd like to know what it takes to turn matter from a nonliving state to a living state. This can be done in the lab through controlled experiments, by investigating all kinds of combinations.
Suzan Mazur: What are the main bottom-up approaches to building the protocell -- Is this the list?: (1) RNA (ribonucleic acid) world, (2) PNA (peptide nucleic acid) world, (3) (CAS) collectively autocatalytic sets, (4) self-reproducing lipid vesicles, (5) mineral surfaces based metabolic processes, (6) cooperative feedback, (7) computational protocells and (8) Aromatic world - PAH (polycyclic aromatic hydrocarbon).
Steen Rasmussen: You've mentioned a whole bunch of them. The bottom-up community seeks to build life from the bottom up, take building block by building block or aggregate by aggregate and put them together, so you can boot the system up and it takes off by itself.
Some bottom-up groups use the most suited starting materials they can find, they'll, e.g., take building blocks from modern cells and try to assemble them in simpler ways. Other groups, including ours, are a little more minimalistic and will not take materials from modern biology. Our group does not use enzymes. We don't use sophisticated lipids and sophisticated metabolic or modern DNA translation machineries.
If you do work with starting materials that have evolved over four billion years and have sophisticated functionalities, you cannot know how these sophisticated functionalities have self-organized in the first place. You don’t address the hard problem, how materials can transition from nonliving to living matter.
We want to understand how the nonliving materials, if you put them together in an appropriate manner, suddenly can become living. It has to do with understanding how matter organizes in a different way.
Think about the following. Look at your arm and then at the clothing you're wearing. If you look at the material the cloth is made of and the material your skin is made of, they are pretty much atom-to-atom, molecule-to-molecule very similar. But the properties of your clothing and the properties of your skin are very different.
If you rip your clothing, somebody has to sew it, but if you scratch your skin, it will grow together by itself. You skin has these marvelous properties and is organized in a very different way than the molecules in your clothing. We're trying to understand what it takes to organize materials so the system can self-repair, can grow and divide, replicate and evolve, adapt, utilize energy efficiently as well as have its entire set of components recycled.
There are fantastic properties we attribute to life. Such properties would be very, very useful for us in engineering if we could make technology that has some of the same properties. That's why I think it's more fruitful to look at the scientific aspect of the Origin of Life problem, i.e., how you can make nonliving material living rather than try to understand historically how that happened, event for event, coincident by coincident.
If we can make artificial living materials, it would have huge implications for technology. We'll then be able to do things much smarter, much more energy efficient and much less resource consuming as all materials are recyclable.
For instance, when you and I die, all our materials can be recycled in the ecosystem. Having technology made up in a similar way for recycling would have great potential.
Understanding the scientific side of the Origin of Life problem opens these kinds of technological possibilities.
Suzan Mazur: Would you touch on microfluidics, which you've described as follows:
"The life-cycle of the protocell is based on the self-assembly and division of lipid (fatty acid) micelles whose growth is driven by a simple photochemical process and controlled via genetic variability of informational peptide nucleic acid (PNA) replicators."
What is the promise of microfluidics for breakthroughs in medicine, including reading of PSA, and insulin levels, etc?
Steen Rasmussen: Yes. It's certainly true that we are very interested in microfluidics and this interface between biotechnology and information technology. But it's not only microfluidics, it is a number of technologies connecting chemistry to information technology. To make it clear, I can maybe tell you a story?
Suzan Mazur: Yes, please.
Steen Rasmussen: This is how I think about it. If you look at science and technology in the last couple of hundred years, there was a major transition at the time of the Industrial Revolution. The essence of what happened is that we found out how to mass produce goods in factories, in an automated manner. At the same time, we built an extensive infrastructure to transport our resources and material goods.
The next really significant technological transition, which we are in the middle of right now, is the Information Technology Revolution. At the center of it is an automation of personal information processing and sharing in the personal computer and the Internet. It has given individuals the ability to access and produce and transmit information everywhere.
So the Industrial Revolution automated mass production of materials in factories and provided a mass transportation infrastructure, while the Information Technology Revolution automated personal information processing and an information access by the computer and the Internet.
Now look at living systems. What can they essentially do? They integrate material production and information processing in the most amazing way.
I believe that the next big technological revolution emerges when we merge Information Technology with material production.
To help us imagine how this material production and information processing could occur, let me first give a little background.
John von Neumann, famous as the inventor of the modern computer, is less known for inventing another machine called the Universal Constructor. Von Neumann proved in the 1950s that machines exist that are able to make everything including copies of themselves, as long as the construction process can be expressed as recipes (algorithms). This defines the Universal Constructor, which is a mathematical machine, which has not yet been implemented. However, it is a machine we often see in science fiction movies. You program the machine and out comes a tool, food or medicine.
We see some of the first primitive examples of such machine with the 3-D printers.
Suzan Mazur: Can you say more about microfluidics used for medical readings -- insulin and PSA, for example?
Steen Rasmussen: One of the wonderful things about Information Technology is that you can program your computer. It's easy to give instructions. But it's very hard to tell a biological cell or biochemistry what to do. At the end of the day, however, all material objects have some chemical composition. So if you want to make new materials, you would need to control some chemical production. How can you instruct chemistry to do that? That's where microfluidics comes in.
You can program the microscopic flow of particular molecules in microfluidics by computers by actuators, e.g., with electrodes or with other means. You are then able to control the chemical production down at the microscale, even down at the nanoscale. So you can make factories that are extremely small. We're still in the infancy of this technology, lab on a chip that can be used by individuals at home.
Suzan Mazur: But you're saying you already have this lab on a chip developed in some form that you can just plug into your computer?
Steen Rasmussen: Yes, but we can only do very simple things. What I'm referring to is the future where we'll be able to have Information Technology and biology or production technology to talk to each other, so you'll be able to program material production in the same way as you program your own computer on your desk today. You'll be able to have a personal fabricator able to make anything.
We’ll eventually be able to implement von Neumann’s Universal Constructor and make it into a Personal Fabricator you’ll have on your desktop just as you have your computer and your printer today.
Suzan Mazur: Amazing.
Steen Rasmussen: We started to walk down this long path implementing simplistic versions of von Neumann's Universal Constructor a few years ago. The Future Emergent Technology Office in the European Commission has already sponsored a portfolio of projects in this direction. It is our technological vision that once we get to the point where we can combine biological systems at the microscale (bottom-up design) with what 3D printers can do (top-down design), we'll be able to have our own material production facilities at home. And then we'll be able to print our own medicine. Print our own clothes. Print our own electronics. We get to a situation where we are the designers, the producers and the user, just as we were before the Industrial Revolution. We’ll have democratized material production.
Suzan Mazur: I'm so glad you're working on it, Steen.
Steen Rasmussen: That's one of the technological derivatives of trying to understand the origins of life.
The intellectual part for me, what has kept me up at night, is this fascination with why materials in certain forms are alive and in other forms are not. Trying to figure out the secret of how to put materials together so they dance and become alive.
Suzan Mazur: Philosopher Jerry Fodor once said that our brains are not wired for the current rush of information. Is there a realization that humans as-is are just not going to make it very far into the future, even on this planet? Is that part of the reason you're developing the protocell?
Steen Rasmussen: No, it's certainly not the reason why I'm developing the protocell. I'm developing the protocell because I have a deep fascination and awe for life and why we are here. I feel really lucky that it's my job, at least part of my job, to try to figure out how life came about and how we can use the properties of living processes to benefit mankind, to make technology with some of these wonderful properties living systems have.
However, I agree, it becomes a bit scary when you think about it on a geological time scale. If you and I as humans create artificial living processes and machines that can copy themselves and ultimately evolve, where will this bring us? Considering that Homo Sapiens is a very, very recent invention in biological evolution, we as humans are naive if we believe we are the end product of evolution. I’m sure we are not. So there's certainly something to think about.
Suzan Mazur: Are you saying you're concerned that we might create a Hal, that Stanley Kubrick's Hal emerges?
Steen Rasmussen: That's right. It’s likely that we’ll help create the next major evolutionary step. To help think about the negative possibilities of this development, we have all the Hollywood horror movie scenarios. Wonderfully described in Terminator and Jurassic Park.
Suzan Mazur: Speaking of Jurassic Park, wasn't complexity pioneer Stu Kauffman, your former colleague at Santa Fe Institute, the inspiration for actor Jeff Goldblum's character Ian Malcolm, the SFI chaos theorist author Michael Crichton invented?
Steen Rasmussen: Yes, that's right, Stu Kauffman was. And Doyne Farmer and I later teased one another about being Crichton's inspiration for scientists in Prey, which has yet to be made into a film. I very much enjoyed Jurassic Park, and I certainly believe such things could happen, but not as described by Hollywood.
Obviously, we are far from being able to do this with technology. But what Hollywood describes is just one direction of a future living, intelligent technology. Another possibility is that we nurture our technology as we nurture our children.
We want our children to be happy, to be as smart, beautiful and insightful as possible as they grow up. We want our children to be able to go out in their world and do all the things they'd love to do.
Thinking along those lines, it might be possible that our technology will enable humans to create "things" that can make more beautiful poetry and art than we can, that can love more deeply and be more compassionate than we can. It doesn't need to be as depicted in Hollywood horror movies.
In any event, this next evolutionary transition does make me a bit uneasy, but I believe we have to move on. Dreaming, having curiosity and having the drive to invent new ways to do things better is one of the beautiful traits of humans.
Suzan Mazur: How far away is the making of a protocell?
Steen Rasmussen: A protocell, is of course, just a little step in that direction.
Suzan Mazur: But when do you think the protocell will happen? Other scientists are projecting within the decade.
Steen Rasmussen: When I look back at what I said about 10 years ago, I believed we might be able to do it in 10 years or so. But we're not there quite yet, and I’ve now been leading research teams on this for the last eight years. How much longer we’ll have to wait for completion in part depends on how lucky we are with our next research grants.
Suzan Mazur: Freeman Dyson said "Give it another hundred years."
Steen Rasmussen: No, no, no… It won't take 100 years. There are a number of groups very close to having what is needed. Gerald Joyce a couple of years ago actually did make a self-reproducing and evolving RNA system. We've put together an information-controlled metabolic production of the protocell components. We still haven't got evolution going yet, but it certainly won’t take another 10 years before we are done.
Suzan Mazur: Are you working with PNA?
Steen Rasmussen: Not anymore. It was too expensive. The penalty I pay for trying to make this as simplistic as possible is that I have to chemically synthesize most of the molecules we use as building blocks. To build these molecules means that I have to employ synthetic chemists. And the more different materials you use, the more expensive it is. To synthesize new chemicals is both very difficult and time consuming.
Suzan Mazur: Is there anyone working in the PNA world now?
Steen Rasmussen: Yes. Peter Nielsen was the inventor of PNA and the proposer of a PNA world. I still think PNA is a beautiful molecule. It's a very powerful one. It's just too expensive for us to use so we found a cheaper way. My lab is combining some of the properties PNA has with DNA. We're modifying DNA, putting oily tails on it so the DNA can sit on the exterior of aggregates. We can thereby get some of the same functionality. I think we could have done it more elegantly with PNA, but it's just too expensive. Working with modified DNA is much cheaper.
Suzan Mazur: Didn't Dave Deamer comment that he thought PNA was a longshot because no one knew if it could reproduce?
Steen Rasmussen: I guess it has been demonstrated that PNA could be synthesized by prebiotic chemistry, but nobody has yet made PNA self-replicate. I think it is possible for PNA to replicate.
But I want to emphasize another problem in this connection. Chemistry is very, very difficult. It is difficult in a different manner than physics is difficult. I'm a physicist, so one of the things I have realized when I put these research teams together is that chemistry is a bit of a black art. It's not like physics -- and it's not that physics is not difficult -- but the great chemists are like the great chefs. They have green fingers. You can have one chemist who can synthesize a particular molecule without any problem. Then you put the other chemist in and he uses exactly the same recipe but the souffle' falls flat. This is what is wonderful and terrible about chemistry. You simply don’t know what you get before you try.
Even though the protocellular systems we are working on are much, much simpler than modern cells, they are still so complicated chemically that it is very difficult to predict whether what we set out to do will work or not. We have to try it out. No theory or calculation can ensure that it will work or not. That makes it very difficult to make timelines and long-term plans, as some innocent-looking chemical step can become a roadblock for the whole project. And then you have to go back to re-try or find new ways around the roadblock.
So I'm more modest as a theorist today than I was10 years ago. I'm more humble, because I've been living and breathing the problems that my chemists have had over the last decade. This is really difficult stuff.
Suzan Mazur: Richard Lewontin has said Darwin intended natural selection as a metaphor. You've been quoted as saying: "Natural selection will apply to artificial creatures, and will favor those with a more efficient metabolism." How is it possible that natural selection is at play in Artificial Life?
Steen Rasmussen: I want to say two things.
First: Natural selection or selection and amplification are part of evolution. Evolution can happen in any material substrate. The substrate does not need to be biochemical. For example, self-replicating computer programs may make copies of themselves with small variations. One of these variations may make the self-replication action a little faster, so that it can make more daughter programs. If we assume a constant population size, more of the fast replicators will eventually be selected for, and you see an evolutionary change in the populations from slow to fast replicators.
Evolution is a physical process, and it can be implemented in many, many different systems. We have computer processes that undergo evolution just as real as evolution seen in bacteria in the lab. Darwinian selection within artificial computer systems has existed for more then 20 years, and the properties are documented all over scientific literature.
There is also selection in society today between technologies, where different possible solutions are put to the market, where certain technologies prevail while other companies have to retool, do something else. That’s just how it is. Evolutionary technological processes are also documented in the literature by following patent records to see how different technologies are related.
So evolution does not just occur in biological systems.
Second, I want to quote one of my old colleagues and friends Walter Fontana from Los Alamos and the Santa Fe Institute. Walter said the problem is not understanding survival of the fittest but understanding arrival of the fittest. How can a system acquire the ability to replicate? You cannot have evolution of a system toward its ability to replicate. Replication is necessary before you can have evolution. Something else has to come into play before you have the first system that can undergo evolution.
Suzan Mazur: Do you mean replicate or reproduce? Some scientists make a distinction between the two.
Steen Rasmussen: I would say replication. To have a system that can replicate is necessary before you have evolution.
How do you get the first system to replicate? There's a process called self-assembly where you can aggregate materials and suddenly get new properties. For instance, if you have a lipid molecule in water, if you allow many, many lipid molecules to swim around in water, then they will form a membrane. Once you have a membrane, suddenly you can design an outside and an inside. You'll be able to define permeability through the membrane.
There are certain materials that can easily pass through the membrane and some materials that can't. It's logically impossible to observe these properties at the level of the individual lipid molecule. When you put things together you get new properties, genuinely new properties. This is a way to generate novelty, putting materials together in new ways.
So, for us to make the first protocell, we can't use evolution -- at least not evolution of the system itself. The way we have to get to a system that can undergo evolution is, we first need self-replication. We need to put materials together in a way such that the result of their interactions is that the whole system replicates. To make that happen you need free energy to drive the whole thing. That’s why metabolism is also necessary as it can drive the replication process.
The individual building blocks of the protocell can't explain the higher-level structure and its functionalities when we put them together. They are an emergent structure. So we have to put a set of appropriate molecular aggregates together to get the first replicator.
This is the big scientific question -- figuring out which materials to put together to obtain a replicator.
It reverts to your original question about the origins of life. Once you have replication, then you can have evolution, but you don't have evolution before you have replication. At least I don't think so.
So when we talk about evolution, there are two important aspects to stress. We’ve already discussed the point regarding replication, but there's also the aspect of how innovative evolution is. Because depending on which evolutionary process you have, it can either be boring and only optimize existing solutions or it can be innovative in an open-ended manner and keep finding new solutions.
Evolution is not just evolution.
Suzan Mazur: Would you comment on your interest in scientists participating more in the public discourse?
Steen Rasmussen: Yes, I'd like to. Over the years I have increasingly felt that science could contribute much more to address societal challenges than is currently the case. Today science and technology are almost invisible in the public discourse. Many policymakers don’t use the best knowledge to make important societal decisions. Too many decisions are based on beliefs and ideologies not on peer-reviewed and double-checked knowledge.
People with a background in the humanities or in the social sciences now dominate the global media and most of the national parliaments in the Western world. This means that we are missing the scientific perspective in our culture. We get an amputated view of the world. A society blind or deaf, missing one of its senses. We all lose out by not bringing science into the public discourse.
Further, there is a cultural war on science in the US and to some extent in Denmark too. We are currently at the bottom of a science-critical wave in contrast to the enthusiasm for science and technology we experienced at the end of the 19th century and the first part of the 20th century. We need a balance, neither extreme is healthy.
Part of the radical political change that took hold in Western societies in the 1960s was also critical to science and technology. It was critical to science because scientists and engineers supported industry, and industry was seen as not doing anything for the common man. Some of this anti-science bias still exists, and many societal decisions are not being based on our best scientific knowledge, for example, regarding climate and energy policy, but also education and immigration policy. In the latter, it is not natural science but social science that is being ignored.
Suzan Mazur: Many scientists are humanists, the artist and scientist are often one.
Steen Rasmussen: That's true. I tried to engage in these science policy issues while I was in the US, but I wasn't able to get real traction, maybe because I was at Los Alamos. At Los Alamos we were engaged with securing the nuclear stockpile, which meant that we had a lot of security. This prevented many such things from happening. But when I came back to Europe I was able to launch another initiative, which is now up and running, called the Initiative for Science, Society and Policy. Its mission is to make science and technology an integral part of the public discourse, to enable natural scientists to engage in the democratic processes.
Suzan Mazur: The fact that you and many other scientists now want to share your insight with the public into Origin of Life and protocell development is excellent.
Steen Rasmussen: I've reached a place in my career where I can allow myself to engage in these issues publicly. I have tenure and I know my university management supports this kind of engagement. However, younger natural scientists or engineers can't afford to do that, as our internal natural science evaluation system is based on our scientific output.
Young scientists who want to have a tenured research job at a university have to focus on their scientific output and nothing else. Engaging in science policy and showing scientific social responsibility doesn't count. If a young scientist wants to have a job, if they want to be successful in industry and in academia, they don't have time to address the public and are penalized if they do. That’s determined by competitive selection for very few academic positions and is one of the main reasons why so few natural scientists or engineers engage with the public. This is contrary to social scientists who are expected to engage, since they obtain academic credits by doing so.
Unless you've set your mark in science or are not afraid of being thrown out of the saddle, you can't engage in public discourse as a natural scientist. And that is tragic.
Suzan Mazur: Life is good in Denmark?
Steen Rasmussen: I've always been pretty happy with what I've been doing, and with where I have been living. It’s wonderful to be right next to the sea again. I just moved to a farm way out in the country with a view over the water. But I do miss life in the American Southwest, which is more in tune with my spirit. I still have many close friends and professional colleagues there and always look forward to visiting.
In Scandinavia, people don't talk to each other in the way they do in the US, particularly out in the American West. Danish society is more closed and non-inclusive.
I also miss the wonderful "can do" spirit in the US. Plus the US 24-hour service cycle for grocery shopping and organizing your life. But I shouldn’t complain. I do enjoy life here.
Suzan Mazur: Are your children inspired by science?
Steen Rasmussen: Yes, I think they are. They certainly have an appreciation for what science is all about. But I have advised my kids not to go into science.
You should only do basic science if you can’t stop yourself from becoming a scientist. Otherwise, it’s too hard and requires too many sacrifices in terms of long hours and lousy pay as a PhD student, a postdoc and a young faculty. It’s in particular very hard to establish a family as you are usually forced to move to another country or region every two or three years of the first 10-15 years of your career. These are not easy conditions for raising a family.
At my science center, I give young people who are interested in basic science all the reasons for why they shouldn't dive into such a career. And I tell then that there's only one thing harder than trying to make it in basic science. That’s trying to make it as an artist. I was married to an artist for almost 20 years and my oldest daughter is an actress and a writer. I also know that from the inside.
For large stretches of my life, I have been working in science for 70-80 hours a week. Fortunately, I don't need to sleep very much, so I’ve had plenty of time to play and explore other parts of life as well. Also, physical activities such as sailing, running and swimming bring me into a meditative state where ideas and solutions can bobble up. It’s both wonderful and exciting to have a job that consists of playing with your imagination and dreaming up new things. But it's not easy to be a partner to such an obsessive individual.
Suzan Mazur is the author of The Altenberg 16: An Exposé of the Evolution Industry. Her interest in evolution began with a flight from Nairobi into Olduvai Gorge to interview the late paleoanthropologist Mary Leakey. Because of ideological struggles, the Kenyan-Tanzanian border was closed, and Leakey was the only reason authorities in Dar es Salaam agreed to give landing clearance. The meeting followed discovery by Leakey and her team of the 3.6 million-year-old hominid footprints at Laetoli. Suzan Mazur's reports have since appeared in the Financial Times, The Economist, Forbes, Newsday, Philadelphia Inquirer, Archaeology, Connoisseur, Omni and others, as well as on PBS, CBC and MBC. She has been a guest on McLaughlin, Charlie Rose and various Fox Television News programs. Email: email@example.com