This value of likelihood is an emergent phenomenon given an environment and an organism.
That said, here are several at least semi-relevant papers that have influenced my thinking on a bunch of things (no particular order).
[1] Wheeler, L.C., Lim, S.A., Marqusee, S., and Harms, M.J. (2016). The thermostability and specificity of ancient proteins. Curr. Opin. Struct. Biol. 38, 37–43. (Probably paywalled but available on the Harms' lab website - https://harmslab.uoregon.edu/publications/. Mike's work on thinking about the biophysics of evolution is in general super cool. Similarly work by Adrian Serohijos is really interesting, although I am in general less familiar with it http://www.serohijoslab.org/publications.html)
[2] Tikhonov, M. (2016). Community-level cohesion without cooperation. Elife 5. (Open Access, really cool, and publishing a single-author original paper in a top journal in this day-and-age is incredibly impressive).
[3] Riback, J.A., Katanski, C.D., Kear-Scott, J.L., Pilipenko, E.V., Rojek, A.E., Sosnick, T.R., and Drummond, D.A. (2017). Stress-Triggered Phase Separation Is an Adaptive, Evolutionarily Tuned Response. Cell 168, 1028–1040.e19. (Paywalled, but IMO a HUGELY important study for thinking about 'aggregation' in the context of cellular fitness)
[4] Chakrabortee, S., Byers, J.S., Jones, S., Garcia, D.M., Bhullar, B., Chang, A., She, R., Lee, L., Fremin, B., Lindquist, S., et al. (2016). Intrinsically Disordered Proteins Drive Emergence and Inheritance of Biological Traits. Cell 167, 369–381.e12. (Paywalled, but potentially one of the most important discoveries in cellular adaptation in decades. More work to be done though!)
[5] Halabi, N., Rivoire, O., Leibler, S., and Ranganathan, R. (2009). Protein sectors: evolutionary units of three-dimensional structure. Cell 138, 774–786. (Paywalled, but super important for thinking about the relationship between local structural coupling and evolutionary behaviour. In general, everything Rama puts out is just gold.)
Still, it seems interesting and I wish you all the best. I hope you are awarded your PhD.
FWIW, this is the submission to my committee, so I'm now spending the next few weeks meticulously going through to tighten up the grammar, catch typos etc., before it gets officially submitted in June.
"We wish to understand mechanism through "
should have been
"We wish to understand the mechanism through "
I had to pause on that spot too because it felt stilted when reading over it, though after reading it again I got what you were talking about and it read fine.
I would probably put different commas:
"but equivalently fit ways then, given the stochastic nature of evolution, this is almost guaranteed to happen"
I suggest this based on intuition alone, but I believe the principle is: http://www.grammar-monster.com/lessons/commas_for_parenthesi...
Probably wise to mention your PhD here on HN. Nerds (apart from me) are the finest proof readers and grammar checkers the world has ever seen.
Seriously, all the best on your PhD submission. Sorry for the confusion.
categorize
(Please don't kill me)
And you're still focusing on too narrow of a spectrum, you can't even be sure that life must follow these rules just that it has in the one example we have.
My personal beliefs are similar but I do expand it to the cosmic stage. I can't answer "why is there something rather than nothing?" But as soon as something exists, either through luck or some plan it does everything it can to ensure it doesn't go back to nothing.
We wish to understand mechanism through the elucidation of design principles, yet evolution does not select for principles, it selects for fitness, an epistatic and emergent property. If similar outcomes can be achieved in different but equivalently fit ways, then given the stochastic nature of evolution this is almost guaranteed to happen. We have specific examples where every statement in the preceding paragraph is true [ed: a collection of proposed mechanisms]. We do not need one person to be right or wrong; our nascent understanding of complex biological systems is that the space of information-processing solutions is astronomical. Think of the diversity observed in structural biology - the repertoire of tertiary structures is enormous. There are countless examples of nearly identical functions being performed by proteins with radically different structure.
This divergence, this variety in structure and function, is what makes evolution robust. It is an inherent bet-hedging mechanism woven into the fabric of statistical physics. On the contrary, the desire to categories and abstract complexity into distinct groups is an inherently human endeavour. Much as we may wish and as convenient as it would be, Nature does not have a plan.