Randomness in Evolution

by John Tyler Bonner

The important role that randomness plays in evolutionary changeJohn Tyler Bonner, one of our most distinguished and insightful biologists, here challenges a central tenet of evolutionary biology. In this concise, elegantly written book, he makes the bold and provocative claim that some biological diversity may be explained by something other than natural selection.With his customary wit and accessible style, Bonner makes an argument for the underappreciated role that randomness—or chance—plays in evolution. Due to the tremendous and enduring influence of Darwin's natural selection, the importance of randomness has been to some extent overshadowed. Bonner shows how the effects of randomness differ for organisms of different sizes, and how the smaller an organism is, the more likely it is that morphological differences will be random and selection may not be involved to any degree. He traces the increase in size and complexity of organisms over geological time, and looks at the varying significance of randomness at different size levels, from microorganisms to large mammals. Bonner also discusses how sexual cycles vary depending on size and complexity, and how the trend away from randomness in higher forms has even been reversed in some social organisms.Certain to provoke lively discussion, Randomness in Evolution is a book that may fundamentally change our understanding of evolution and the history of life.

Genres: Science, Biology, Evolution, Nonfiction

141 pages, Kindle Edition

First published January 1, 2013

About the author

John Tyler Bonner is the George M. Moffett Professor Emeritus of Biology at Princeton University, a pioneer in the use of cellular slime molds to understand evolution and development, and one of the world's leading experts on cellular slime molds.

Reviews

[Mohamed al-Jamri · Rating 2 out of 5]

جذبني موضوع الكتاب، وحسبته سيتحدث بصورة موجهة للعامة عن دور العشوائية في التطور، إلا أنه كان كتاب تقني بصورة كبيرة جدًا ولو أن به قدرًا لا بأس به من التبسيط.

يقسم الكاتب النظرة للكائنات الحية إلى نظرة كبيرة وصغيرة ويشرح بأسلوب ضعيف نوعًا ما كيف يخرج لنا النظام من رحم العشوائية من خلال عملية التطور. لعل أهم نقطة ركز عليها الكاتب هي أنه وبالرغم من الدور الكبير الذي يلعبه الانتقاء الطبيعي في التطور فانه ليس القصة بأكملها، فهناك دور كبير تلعبه العشوائية، خصوصًا فيما يتعلق بالكائنات البسيطة نسبيًا. ويقل دور العشوائية كلما أصبحت الكائنات أكثر تعقيدًا، وبالتالي يبرز دور الانتخاب الطبيعي.

كذلك يتطرق الكاتب لبعض المراحل التطورية المهمة مثل الانتقال من الخلايا البروكاريوتية البسيطة إلى الخلايا الإيوكاريوتية الأكثر تعقيدًا، والانتقال من الكائنات ذات الخلية الواحدة إلى تلك متعددة الخلايا (النباتات والحيوانات). ويطرح عددًا من الأسئلة من قبيل: لماذا لا تزال هناك أنواع بسيطة من الحياة على وجه الأرض ولم تتطور أو تنقرض؟ وما هو حجم الدور الذي يلعبه الانتقاء الطبيعي في التطور؟

أكبر سلبيتين في الكتاب في أسلوبه الضعيف في تقديم المعلومات وخوضه في كثير من الأمور والتفاصيل التقنية التي يصعب على غير المتخصص فهمها.

[Fabio · Rating 3 out of 5]

I'll start by confessing that my rating is a bit unfair because it doesn't seem to reflect this is actually a good book, clear and concise. But I have never quite enjoyed biology all that much, it has always felt like homework to me and this book is not an exception.

I put myself through it because (a) I really believe in reading outside your own bubble and (b) I wanted to understand better which nuance was Tyler Bonner, professor emeritus at Princeton, putting on "randomness" (Was he saying it wasn't really random? was he talking about drift/founder/bottleneck effects?). In case you're curious but also mildly bored (no offense if you love them) by slime molds, alleles and prokaryotes here's the cheat sheet:

1. There's more randomness at the bottom. Small and simple organisms enjoy much more randomness because changes are not as lethal. If the embryo of a complex organism has a mutation early in the construction process it will die (this is called internal selection). Only the late-in-the-construction-process mutations are presented for natural selection. In more complex organisms with many more construction steps this means less phenotypical randomness.

2. Selection reigns supreme but randomness plays a bigger part than "pure adaptionists" think. The author shows how simple organisms (and larger organisms like ants) can have all sorts of variations and mechanisms that affect evolution but are not culled by adaptation they rather coexist and/or are randomly drifted.

As far as I can tell, that's it, which is actually very interesting, but I'm sure that people who enjoy biology more will find it much more enjoyable than that.

[Chris Esposo · Rating 5 out of 5]

Good summary of how randomness interacts with Darwinian selection from the systems perspective in biology, with an especial emphasis on cell-level interactions. Written by one of the early contributors to this school of thought (if not one of the originators?), who passed just a month or so ago.

The topic is one that I've struggled to understand personally, which mostly stems from my perception that though randomness is well defined mathematically, selection is not, and it's very difficult to ascertain was percentage each contributes to the path-of-evolution. Though in recent years, the concept and term have been bandied about by many people. It's especially applied haphazardly towards the social sciences e.g. pop psychology where every observed human or group idiosyncrasies are viewed from the perspective of evolutionary social gain. A cursory look at recent "evolutionary psychology" or "evolutionary sociology" text and monographs will see a plethora of topics ranging from the evolution of beauty, to how certain economic behaviour is informed by evolution. Perhaps not all of these notions are not without merit, but I suspect many of them are.

This author's contention is that not every observed change in an organism can be attributed to natural selection or competitive gain (or loss) and that many of the morphologies observed in organisms in the fossil record or it's phylogentic tree, probably are what the author calls "Neutral Morphologies". Neutral morphologies are forms or elements of forms, that may not have a (measurable) positive or negative impact on the organism with respect to competitive advantage in local ecology. He outlines a simple hypothesis test to validate these ideas, though no data or process is outlined in this short text itself. Given the brevity of the book, this is not a demerit.

The author's observation is that if it was the case that selection was mostly informing the path of evolution and development of these morphologies, it would not have generated as many different forms observed in the record, since one would presume a less constricted set of morphologies would serve as a local maximizer for the given scope of a local ecology. This leads to the author's other supposition, that incidence of selections (and it's impacts) is related to the size of the organism, and that size itself was something driven by selection. Specifically, it was a strategy deployed in an arms race between predator and prey, from single cell, to multicellular organisms, and even larger animals like reptiles, mammals etc. This part of the book is where the author leverages the systems perspective most, and it is convincing. The author illustrates how size could have started mechanically at the cell-level, with the adaption of adhesive-like substances to bind together colonies of cells, and how the internal insulated structure would lead to an advantage for those cells, relative to cells operating free-form in the external environment.

Overall good listens, anyone interested in understanding selection deeper or evolution in general should pick this one up. Recommended

[Troy Blackford · Rating 4 out of 5]

A short (the author calls it an 'essay') and highly technical work. It was thought-provoking, difficult, and not entirely convincing. I am glad I read it, and I will mull it over, but this is another for the 'overturning the fundamentals of biology with a theory' pile, and I haven't seen a huge response to the theories here from others. Still, lots to think about and lots of solid facts that were new to me and interesting to consider.

[Justin Tapp · Rating 3 out of 5]

**I read Andreas Wagner's Arrival, John Tyler Bonner's Randomness in Evolution, and David Deamer's First Life: Discovering the Connections between Stars, Cells, and How Life Began subsequently, so my review is meant to be read relative to the other two as all three overlap in subject matter. (This paragraph appears in all three reviews). I am reading these books after reading several on cosmology.* I wanted to move beyond what cosmologists say (with disagreement) about the formation of the universe to see how it could be compatible with what chemists and biologists say about the beginning of life. Alan Lightman writes in the Accidental Universe that "Science can never know how universe was created," and I find that to be echoed in these books -- science can never know or prove how exactly life began (Deamer states this outright). Exactly what chemicals were available on earth to mix in what quantities to randomly create a reaction between molecules that led bonds to form, information to be transmitted, and growth to begin? All of the hypotheses presented in the books require certain laws of physics and nature to hold but I have not found any who attempts to explain how those laws arose in the first place. Why are these laws what they are? Call this the Paul Davies critique. http://www.nytimes.com/2007/11/24/opi...
Deamer acknowledges that it's possible a creator put those laws into existence, but the other two avoid the subject. None of the three seem to recognize that chance is not a causal force, so time + chance cannot explain anything.
Where did light come from and how did it contain information? How did cells know that it contained information and figure out a way to receive and decode it? How do "regulator cells" operate according to these laws? What is consciousness and at what point is life "life" such that it has "value?" All three of the authors reach the same conclusion as the cosmologists above-- we are a random collection of atoms that will one day be scattered, nothing more nothing less. Life has no meaning outside of a debatable definition regarding complex molecular processes, and any sentiment we attach to it is illogical-- there is no soul in science. I do not, therefore, understand how Lightman, Hawking, Richard Dawkins, etc. can argue that scattering people's atoms is "wrong," or where they get ethics. We're not special, only lucky in the sense of randomness.

These three biochemist authors, however, engage in less armchair philosophy than Hawking et al, and (unlike string theorists Hawking and Green) argue that science requires testable hypotheses and that the universe had a beginning. Each of these books have a good look at what actual laboratory research looks like. These are not just men working equations at a desk all day, although there is some of that. They're often out traveling the world in search of mineral samples and in the laboratory mixing chemicals in the search for the genesis of life. My next set of books will be on the scientific understanding of consciousness-- something these books do not address.**

There are essentially two premises in this book:
1. Randomness explains more of the variety of the life we see today than natural selection.
2. The effect of randomness varies depending on the size of the organism-- the larger the organism, the less variety of morphology can be expressed.

As a student of Daniel Kahneman and Nicholas Nassim Taleb, I enjoyed the same critique applied to the evolution of species that these apply to the wizards of wall street-- success is determined more by randomness, but our hindsight bias makes us think we see skill. Bonner argues that randomness is more important than adaptation/natural selection, in which certain traits evolve somehow to give the organism an adaptation it did not previously have. Randomness has to happen before natural selection can happen, "there can be no natural selection without randomness." So randomness is the "skeleton in the closet," that most "naturalists" would rather not think about. But he doesn't "throw Darwin out with the bathwater," these processes work together. "All of evolutionary change is built on a foundation of randomness. It provides the necessary material for natural selection which then does indeed bring forth the order our inner mind so actively craves." Natural selection by itself tends to ask for an intelligent designer because how else would a cell know what information to pass down, or how would "regulator cells" need to know what cells to form next? Bonner immediately discards creationists as fools. But I imagine some of these fools would be quick to point out that chance itself is not a causal force-- time + chance cannot produce something ex nihilo. Something isn't "caused" by chance, and to his credit Bonner is careful not to state it this way.

How do you know if something is an adaptation or randomness? So many times we consider an adaptation to be an adaptation because of hindsight bias when actually it was random mutation that just worked. Our biosphere today is the result of 14 billion years of these compounded mutations. Likewise, the maximum possible size of organisms increase over the millenia. Bonner describes the difference between prokaryotes and eukaryotes, from Nature.com: "In prokaryote cell organization there is a nucleoid containing genomic DNA but it is not surrounded by membranes such as what defines the eukaryote nucleus (Martin & Koonin 2006). Eukaryotes such as fungi, protozoa, plants, and animals, and thus we humans, have cells with complex structure with internal membranes and membrane-bounded organelles." http://www.nature.com/scitable/topicp...

He discusses morphology and neutralism. He seems to answer the layman's question as to why we don't see more variety of species that have been around for millions of years. Even if morphology changes very little, an organisms biochemistry can change much. Whereas Wagner (Arrival of the Fittest) seems to argue "junk genes" and traits with no purpose are evidence of a previous purpose in an ancient environment, Bonner seems to argue that these were random mutations that did not really make a difference to an organism's survival, so they were not weeded out. Bonner's focus on research are slime molds.

I think one weakness of the book is in the discussion on how organisms evolve from single-cell to multicell. Bonner cites division of labor in developed organisms in nature and relates it back to multicell organisms. Bonner does a good job supporting his hypothesis about how processes differ in small organisms and larger organisms. Size matters just as randomness matters.

I give it 3.5 stars. It definitely earns points for its concise nature, this is the shortest of the three books. It is written a bit more toward the layperson than Andreas Wagner's Arrival. I would like to read counterarguments.

[Craig Becker · Rating 4 out of 5]

John Bonner’s Randomness in Evolution (2013) was a different read for me—I’ve been focused lately on books about intentional improvement and creating better outcomes. Bonner keeps pulling you back to the quieter truth that evolution is built on chance. He doesn’t dismiss natural selection, but he argues convincingly that randomness (mutation, recombination, drift, founder effects) is the essential foundation that supplies the variation that selection can later filter.

What I found especially useful is his lens on time, size, and complexity. As organisms get larger and development becomes longer and more layered, randomness is often screened out by developmental bottlenecks (“internal selection”). In contrast, smaller organisms can express and retain more neutral variation. Forms that persist without obvious adaptive superiority. That connects directly to Daniel Milo’s "Good Enough: the tolerance of mediocrity in nature and society," by Daniel S. Milo, ©2019, the idea that much of life survives not because it’s best, but because it’s not bad enough to disappear.

This also connects to Deming. Deming taught that improvement isn’t understandable, let alone repeatable, unless the process is under control. In manufacturing, that meant stabilizing the system so variation is visible, and learning is possible. For health, the parallel is clear: the lifestyle process plays the role that the manufacturing process played for Deming. We need a stable baseline of automatic, health-promoting routines, food, movement, relationships, and development so we aren’t living in constant noise and recovery mode. Once the lifestyle process is under control, we can measure, learn, and improve deliberately, freeing energy and attention to become who and what we want to be, while also generating benefits for ourselves, our communities, and the planet.

If you like evolution explained as neat, linear optimization, this book will challenge you. If you want a more realistic picture—messy, probabilistic, and still capable of producing meaningful order—it’s well worth reading.

[John Deitsch · Rating 4 out of 5]

This is one of those books that creationists will pick a few quotes from for blogposts and YouTube videos about how evolutionists are abandoning evolution… or something.

Anyway, the book reads a bit like the ramblings of an old man. But I knew that going in so this does not affect my review. If I was expecting a more, shall we say, calibrated (?) look at the topic, I may have been disappointed.

My interest in the subject is probably why I give this a four stars, plus the cover is beautiful. I do wish slime molds were less the star of the book… I cannot say I am too interested in them, beyond their relevance for cutting edge evolutionary thought experiments!

[Douglas · Rating 4 out of 5]

Bonner is always a clear writer. The neutral phenotypes model he advocates for small-sized organisms generates predictions, and he should be explicit about these. Neutrality is sort of a null hypothesis (not really) but nevertheless a very strong one, and it would be good to know which predictions Bonner favours and which not so much.

I suspect that this will fail in the same ways Hubbell’s does at a wildly different scale, but it is interesting nonetheless.

[Teo]

2017.01.16–2017.01.16

Contents

Bonner JT (2013) (02:44) Randomness in Evolution

Illustrations
Preface

1. Life and the Riddle of Randomness
2. Time, Size, and Complexity
3. Small Organisms and Neutral Morphologies
4. The Evolution of the Decrease of Randomness
5. An Exception: Where Small Organisms Suppress Randomness
6. The Division of Labor: Two Cases of the Return of Randomness in Higher Forms
7. Envoi

Acknowledgments
Bibliography
Index

[Atila Iamarino · Rating 2 out of 5]

Achei um livro absurdamente curto e simples, que poderia ser resumido a um artigo ou um texto de opinião. Fiquei com a impressão de que ouvi uma versão resumida de algo mais completo, não consegui me prender à leitura nem lembrar de nada proveitoso.

[Douglas · Rating 4 out of 5]

***WARNING***
If you are not at least familiar with the basics of biology, you will get lost.
Though the book is small, it is dense and informative. I have always been interested in the randomness part of evolution, and Bonner does give new information that I had not thought about.

[Tharindu Magedara · Rating 2 out of 5]

Honestly followed very little of it, it was out fo my depth technically. On top of that I thought it was poorly presented with lack of clear cut examples and empirical conclusions.