Astrobiology can be split into two very distinct fields. There’s the field that astronomers are likely more familiar with, involving large telescopes, exoplanets, and spectroscopic signals that are pored over to debate whether they show signs of life. But there is another camp, collective known as the Origins researchers that focus on developing a scientific understanding of how life originally developed on Earth. A new paper from Cole Mathis at Arizona State and Harrison B. Smith at the Institute of Science in Tokyo suggests a new path forward to tackling those challenges - set them up as competitions and let a hefty prize motivate scientific teams and individuals to pursue them.
The paper, which was published on arXiv, is a response to NASA’s Decadal Astrobiology Research and Exploration Strategy (DARES) call for community input. It calls on the “challenge” funding model popularized by organizations like the X Prize, and the Defense Research Advanced Projects Agency (DARPA), whose early autonomous driving challenges inspired the self-driving cars that are finally starting to navigate public roadways.
A similar method could be used to stimulate research into specific, measurable, and important “origins” research according to Drs. Mathis and Smith. They point out that one hurdle holding back development in this field is a lack of consensus on even simple definitions, such as “what is life?”. However, they lay out five different “finish lines” that, though some of them would prove certain theories, lack of progress towards them could also be held up as proof of opposing theories.
Fraser interviews Mary Volek, the longtime head of NASA's astrobiology program.One finish line will attempt to solve the debate of whether metabolism or genetics were developed first in the course of life. It focuses on creating a biological pathway known as the pentose phosphate pathway (PPP) using abiotic chemistry. If possible, it would make a strong case that the “metabolism first” camp is correct.
A second finish line utilizes the concept of “assembly theory”, a framework developed by Leroy Cronin and Sara Walker, that quantifies the complexity of organic molecules, and draws a distinct line at a certain complexity level, showing that anything more complex must be made within a biological system. The challenge the authors put forward is to create a sufficiently complex molecule using only abiotic chemistry.
The third challenge attempts to settle the debate between “determinism” and “contingency”. In the determinism world view, if we manage to rewind life back to its early beginnings, would the same process happen in the same way all over again if given the same starting conditions? Or, according to the “contingency” theory, would small differences in the chemistry makeup of early life lead to massive differences in the biochemistry of later lifeforms. The challenge itself is to design an organic chemistry experiment where exactly the same initial conditions can lead to different products. If someone manages to do this, it would prove the “contingency” theory of early life formation.
Fraser interviews Wallace Arthur, an expert on evolutionary biology.The fourth challenge tackles self-replication, by requiring a team to make polymers that can self-replicate but still overcome “Eigen’s error threshold”. According to the information theory developed by Manfred Eigen that goes along with replicators passing data to the new copies of themselves, early replicators would have to be much smaller than would be necessary to contain any error-correcting biological machinery common when our cells copy their own DNA during the replication process. Understanding how early life got through this bottle neck to develop reliable error checking systems without losing all their information once they cross the threshold in terms of size is at the problem at the heart of this challenge.
Scientists have long thought that, somewhere in the process of evolution, there was a transition from RNA to DNA. However, that has never actually been proven, and the fifth and final challenge pushes researchers to prove that the RNA to DNA jump can be made gradually. If such a jump is infeasible, that would call into question the significance of RNA in the overall scheme of the development of life on Earth.
These challenges are well defined, measurable, and have an obvious tie back to the fundamental challenge of understanding where life originally came from. Whether or not NASA, especially with its own current funding challenges, would be willing to back a challenge-based structure to pursue these efforts remains to be seen. But there are plenty of other challenge-based funding supporters out there, such as the team around the Evolution 2.0 challenge and the X Prize itself. Astrobiology research remains key to understanding our place in the universe - it might be time to consider a different path to how we approach it.
Learn More:
C. Mathis & H. B. Smith - Challenge-Based Funding to Spark Origins Breakthroughs
UT - Astrobiology: Why study it? How to study it? What are the challenges?
UT - NASA's Future Telescope Could Solve the Mystery of Life's Origins