Replaying the tape of life: Is it possible?

November 8, 2018, Washington University in St. Louis
Credit: CC0 Public Domain

How predictable is evolution? The answer has long been debated by biologists grappling with the extent to which history affects the repeatability of evolution.

A review published in the Nov. 9 issue of Science explores the complexity of evolution's predictability in extraordinary detail. In it, researchers at Kenyon College, Michigan State University and Washington University in St. Louis closely examine evidence from a number of of evolutionary repeatability and contingency in an effort to fully interrogate ideas about contingency's role in evolution.

The question of evolution's predictability was notably raised by the late paleontologist Stephen Jay Gould, who advocated the view that evolution is contingent and unrepeatable in his 1989 book Wonderful Life. "Replay the tape a million times ... and I doubt that anything like Homo sapiens would ever evolve again," Gould mused, noting that being able to "replay the tape" and give history a do-over would be impossible. Yet since the publication of Wonderful Life, many evolutionary biologists have taken up this challenge and conducted their own versions of Gould's experiment, albeit on smaller scales. In doing so, they have reached different conclusions about the interplay between randomness of mutations, chance historical events, and directionality imparted by natural selection.

"How history plays out isn't really predictable. Historical outcomes are contingent on long chains of events loaded with tiny little details. A dropped packet of cigars wrapped with the Confederate army's marching orders was found by a Union soldier, which led to the Battle of Antietam, which led to Lincoln announcing the Emancipation Proclamation. What if those cigars hadn't been dropped, or if they hadn't been found by a Union soldier? Evolution is similar, in that it plays out over vast periods of time with long, unique chains of events involving a lot of chance. Unlike history, though, evolution has the deterministic force of natural selection, but that determinism is always in tension with the chanciness. How does that tension affect what evolves? Which is more important: contingency on details of history, or determinism?" said Zachary Blount, a senior research associate at MSU and visiting assistant professor of biology at Kenyon College who served as lead author of the review.

Blount was joined in his work by Richard Lenski, the Hannah Distinguished Professor of Microbial Ecology at MSU, and Jonathan Losos, the William H. Danforth Distinguished University Professor at Washington University in St. Louis.

"The idea of replaying life's tape—having a fresh start—is something almost everyone has thought about at some point in their own lives. It's also something that has long interested biologists, but on the grand scale of the history of life on Earth," Lenski said. "Since Gould introduced the metaphor of replaying life's tape, many studies have tried to characterize the repeatability of evolution. What our review shows is that there's no easy answer: Sometimes evolution produces strikingly similar solutions, and other times evolving lineages take very different paths even under the same circumstances. I think that's part of the fascination and beauty of evolution, that it produces both the expected and unexpected, perhaps like in our individual lives, but on a vastly larger scale."

Gould's thought experiment still stimulates robust debate, in part due to inconsistencies Gould introduced in how he described his replay metaphor, as well as confusion around the concept of contingency. Gould often conflated two common meanings of "contingency": as dependence on something else, and as a chance event.

"There are multiple, different literatures on Gould's idea, and these literatures are not talking to each other," Losos said. "There are microbial evolution studies. There are all the studies of convergent evolution, or lack of convergent evolution. And there's also a philosophical literature on what Gould meant when he said, 'replay the tape.' That is, more generally, when you talk about the role of contingency—which is the term Gould used—what does that actually mean?"

Their review of existing empirical studies focused on primarily on three types of "replay studies": laboratory evolution experiments with fast-evolving organisms; experiments carried out in nature; and natural experiments that compare lineages that evolved under similar conditions. The comprehensive analysis revealed a complex picture of evolutionary change in which both contingency and determinism are evident.

Blount, Lenski and Losos examined a number of different types of laboratory experiments, including parallel replay experiments, in which identical populations of an organism are separately evolved under identical conditions, and analytic replay experiments, in which specimens are frozen from a parallel replay experiment and then resurrected and re-evolved from different points in time. This review included study of the long-term evolution experiment with Escherichia coli (LTEE), started by Lenski in 1988. The LTEE has followed 12 populations of E. coli, founded from a single clone, for more than 70,000 generations. Samples of each population were frozen every 500 generations, allowing researchers to directly compare the evolving bacteria with their ancestors.

Blount, Lenski and Losos also examined experiments that attempt to replicate evolution in natural settings. Only a few such experiments exist to date, and their review of these experiments indicated a high degree of repeatability in evolutionary responses to different historical conditions.

Their review of comparative studies of "natural experiments" further illuminated evidence of evolution's predictability. Similar features can independently evolve in multiple species—for example, anole lizards of the Caribbean, which separately evolved traits such as the length of their legs and tails to ease their life in their specific habitats. Yet convergence in evolution does not always occur, as their review shows; contingency can play a strong role in divergent of various traits.

"What we clearly see is that both convergence and lack of convergence occur a lot in the natural world," Losos said. "It's not useful just to keep adding to the two lists. The real question that people are now turning to is: Why does convergence occur sometimes and not others? That is where research is now headed. That's the question we need to focus on."

Explore further: Biologist's new book details a new era in the study of evolution

More information: "Contingency and determinism in evolution: Replaying life's tape" Science (2018). science.sciencemag.org/cgi/doi … 1126/science.aam5979

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rhugh1066
4.8 / 5 (16) Nov 08, 2018
I've read Gould's book and I think his overarching point is that evolution will not produce the same exact designs twice. There will be flight and echo-location and balancing tails and perhaps even intelligent bipeds but they will not duplicate that which has already evolved. The incalculable variables involved preclude it.
Bart_A
1.2 / 5 (22) Nov 08, 2018
Evolution is inherently non predictable, because it is a very very weak theory at best, has never been observed, and cannot be reproduced anywhere. Trying to predict something out of it for the future is absurd. It is like trying to predict tomorrow's weather by staring into a magic glass ball.
Ojorf
4.5 / 5 (22) Nov 08, 2018
Evolution is inherently non predictable, because it is a very very weak theory at best, has never been observed, and cannot be reproduced anywhere. Trying to predict something out of it for the future is absurd. It is like trying to predict tomorrow's weather by staring into a magic glass ball.


Or it's because variability is due to mostly random mutations.
Trying to comment on science while ignoring evidence and basing your beliefs on a magic imaginary person is absurd. It is like trying to predict tomorrow's weather by staring into a magic glass ball or talking to a magic invisible friend.
Captain Stumpy
4.8 / 5 (19) Nov 09, 2018
@barf
because it is a very very weak theory
a scientific theory is "an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results. Where possible, theories are tested under controlled conditions in an experiment" - https://en.wikipe...c_theory

... has never been observed
wrong again: http://myxo.css.m...dex.html

http://science.sc...304/1147

http://chipojolab...86-9.pdf

and cannot be reproduced anywhere
except you're wrong yet again: Richard Lenski et al, Dr. Danielle Whittaker, Dr. Cassandra G. Extavour

That is three strikes, bubba
Epic failure

perhaps you should pray for the capacity to comprehend science?
We'll see how that works, eh?
FredJose
1.2 / 5 (21) Nov 09, 2018
@Stumpy,
Please man, just supply us with a rigorous definition of evolution so we can all play on a level playing field.
Right now there is a terrible overlap between what is meant by Darwinian evolution and speciation or adaptation.
So the reputability of your version of evolution will depend on what you are looking for.

In my mind, whenever I hear "evolution" I immediately assume Darwinian Evolution because that is the real BIG issue. Speciation and adaptation we can easily observe in our lifetimes and we can see it repeated. The big thorn in the flesh of evolutionists is that Darwinian evolution (changing from one kind of organism into another kind, e.g. microbes to amoebas or hydras or microbiologists) has NEVER been observed and cannot be repeated. Such Darwinian evolution is actually just impossible because all random mutations and natural selection can do is cull information, not create new novel structures and SYSTEMS as required.
FredJose
1.2 / 5 (21) Nov 09, 2018
AS for this research on repeat-ability - it's headed for a stone wall since darwinian evolution NEVER occurred.
Our own daily experiences and those of all past living mortals indicate quite clearly that the idea of darwinian evolution (one kind of creature morphing into another over long generational periods, which is not speciation or adaptation ) just doesn't cut it. No one has ever observed such a thing, EVER.
Adaptation and speciation happens as a result of built-in sensing and response within a limited range of variation.
These kind of sense-response action can be observed in real life with very careful and highly complex techniques. No need for speculation or mythical story-telling.

So once again I issue this challenge to evolutionists:
Please come up with a scientifically rigorous definition of "evolution".
Right now, it's a bait and switch game.

But maybe that how you'd like it to remain because it will protect the religion that depends on it?
HeloMenelo
5 / 5 (16) Nov 09, 2018
Aaah a topic which spurrs amusement.
To answer the first question of this article:

Very predictive indeed, in the case of antigoracle and his own puppets, however for him to even make an appearance on the evolution tree of life, you would need to make space on the left next to the ape to the very left of the picture
thingumbobesquire
1 / 5 (2) Nov 09, 2018
Substance itself possesses a latency by virtue of an overriding harmonic dynamism. This is what Leibniz called pre-established harmony. So evolution is confined to a projectory based upon a global order. It is not pre-determined that such and such will occur, only that such and such if it occurs will evolve toward a higher or lower state of potentiation.
KubsKobit
1 / 5 (2) Nov 09, 2018
Jacob heard that Laban's sons were saying, "Jacob has taken everything our father owned and has gained all this wealth from what belonged to our father." 2 And Jacob noticed that Laban's attitude toward him was not what it had been. First episode!
Captain Stumpy
4.6 / 5 (10) Nov 09, 2018
@Fred
just supply us with a rigorous definition of evolution
1- you've been provided this in the past and you still didn't read it?

2- start here: https://www.brita...c-theory

or here, as it has references you can validate the information from: https://en.wikipe...volution

Right now there is a terrible overlap between what is meant by Darwinian evolution and speciation or adaptation.
So the reputability of your version of evolution will depend on what you are looking for
considering science advances based on evidence and validation, it's ridiculous to make the assumption that the theory has never once changed since Darwin proposed it

moreover, a theory in science, as noted above, specifically means that it's based on validated evidence, therefore your claim is negated

you can't build a strawman on the premise simply because you believe the premise to be true

2Bcont'd
Captain Stumpy
4.6 / 5 (10) Nov 09, 2018
@Fred cont'd
In my mind, whenever I hear "evolution" I immediately assume Darwinian Evolution because that is the real BIG issue
1- see above

2- it doesn't matter what you believe in your mind. what matters is what can be validated with evidence. Evolution, the Theory, still has nothing to do with what you believe about it
has NEVER been observed and cannot be repeated
well, you've obviously ignored the above links

if we're going to continue, you will either have to accept evidence that is validated or be relegated to the religious fanatic corner

If you can't actually validate your claims
AND
you can't comprehend the science
THEN
you will never be able to proceed any further, let alone converse intelligently

this is the chasm segregating religion and science
Such Darwinian evolution is actually just impossible
*links* *references* prove you wrong

2Bcont'd
Captain Stumpy
4.6 / 5 (9) Nov 09, 2018
@fred cont'd
AS for this research on repeat-ability - it's headed for a stone wall since darwinian evolution NEVER occurred
ah. the strawman based upon a false claim leading to your justification for your belief

Just because you don't understand it doesn't mean no one does
I'll link this here for you yet again: http://www.talkor...comdesc/

Right now, it's a bait and switch game
I've never baited and switched

You still can't comprehend the evidence
You have *yet* to actually address any evidence that has been produced and validated
You have *yet* to actually produce any scientific evidence
But maybe that how you'd like it to remain because it will protect the religion that depends on it?
1- it's a Theory. re-read that definition that you're still ignoring

2- IDGAF about the Theory. I care about the evidence
the evidence supports the Theory
If the evidence states otherwise I will accept it's successor

end of story
Captain Stumpy
4.6 / 5 (10) Nov 09, 2018
@fred
@barf
So once again I issue this challenge to evolutionists:

Please come up with a scientifically rigorous definition of "evolution".
until you can comprehend the definition of "Science", you cannot comprehend what "a scientifically rigorous definition" is

until you actually learn the scientific method, you cannot comprehend how "a scientifically rigorous definition" is determined

this isn't a semantic argument you're asking for, it requires technical details that also then require comprehension and understanding of at least the basics

until you learn the basics, you will never comprehend the rest

Old_C_Code
3.4 / 5 (5) Nov 09, 2018
A big question is why evolution occurs in quick spurts of time? i.e. many many new species arise in a very short geological time, repeatedly.

Genetics show evolution is a strong theory, just a question of how things mutate so fast in spurts.
Captain Stumpy
4.6 / 5 (9) Nov 09, 2018
@Old C
A big question is why evolution occurs in quick spurts of time? i.e. many many new species arise in a very short geological time, repeatedly
and it's a good question as well as being investigated

there are times when pressures can produce rapid change: http://chipojolab...86-9.pdf

there are several other studies published all around the Journals about rapid evolutionary changes
PO has published articles on this in the past few years
See also: https://scholar.g...volution

Another note: the Lenski, Dr. Danielle Whittaker, Dr. Cassandra G. Extavour experiments and papers have been very promising in how mutations happen in fast spurts
torbjorn_b_g_larsson
3.3 / 5 (7) Nov 09, 2018
The research looks good as expected - Lenski is an author - but the article based on the press release is not.

- A main point of the work is that convergence is broadly defined and that "the [entire] tape" cannot be replayed. From the Structured Abstract: "... repeatability is common when the founding populations are closely related, perhaps resulting from shared genetics and developmental pathways, whereas different outcomes become more likely as historical divergences become greater. ... at least when defined broadly (e.g., at the level of genes, not mutations).

- Minus points for using a non-evolutionary illustration. Chimps evolved knuckle walks, while the common ancestor of hominids looked more like the second individual from the left; in that sense humans are more like the ancestral form.

evolution occurs in quick spurts


Open question. Here is a work that says it can be observational bias: https://onlinelib...vo.13593
torbjorn_b_g_larsson
3.8 / 5 (10) Nov 09, 2018
And the creationists are trolling. Not much to respond to since they make no sense or else makes lies.

Just some basic notes:

Evolution is inherently non predictable, because it is a very very weak theory at best, has never been observed, and cannot be reproduced anywhere.


So the article directly reject the two latter falsehoods. More, anyone can visit an open biology database like NCBI, download free software (to quicken it, of course one can redo) and free data and learn how to test evolution from own laptop within half an hour, repeatedly, for as long as one lives. No hiding under troll bridges here!

But as a point of skewering this utter baloney, evolution has produced ***the most precise observed fact in all of science*** since a last universal common ancestor is more likely than several by a factor > 10^2000 (due to the combinatorics of lineage trees). It is the very complexity of the process - and its statistics - that means many tests are doable,
torbjorn_b_g_larsson
3.2 / 5 (9) Nov 09, 2018
just supply us with a rigorous definition of evolution so we can all play

And later this balloney troll again repeat that the work in discussion just rejected (of 'not observed, not reproduced'). If you don't know the science, don't comment, ask.

So the question could be "how is evolution defined in Evolution 101?" Several definitions naturally, since it is a science and not philosophy - try to define life! yet we can science the shit out of it as seen in the work here - but the broadest is perhaps "change in population genomes over generations". Which is observed and is roughly repeated since evolution makes small changes so roughly same species in the next generation, for an obvious and trivial sense of repeated by evolution. (I hasten to add that this was not the sense studied by the scientists.)
TheGhostofOtto1923
2.7 / 5 (3) Nov 09, 2018
Only so many possible forms, only so many possible combinations. I think that eventually we will be able to take a collection of fossils of a given species and be able to extrapolate exactly what organs those bones contained, what muscles were attached to them, what digestive systems powered them, and what brains controlled them.

I think we will eventually know enough about life and all it's possible variations to be able to rewrite the genomes of long-gone species, and to recreate them at will, just from the information we can glean from their fossils and from what we know about their relatives that are alive today.

We'll work our way backward through time and species, reconstructing as we go. We'll decode evolutionary genomes - genomes of evolving lines, from species to preceding species, the way we are decoding existing isolated species today.

This will be made possible with AI and quantum processing.
TheGhostofOtto1923
2.7 / 5 (3) Nov 09, 2018
And let's not forget, instantaneous access to all accrued knowledge. A verified, dependable database of all human knowledge, all cross referenced, all available to machine minds with unlimited processing power that can begin to make comparisons and draw conclusions that we could never hope to accomplish or imagine.

Like ice-9, the emergence of a singularity that spreads order systematically, efficiently, and with breathtaking rapidity through the sum total of all that we know, converting, solidifying, rationalizing it.

Order from Chaos. Our primary Mission.
torbjorn_b_g_larsson
3.3 / 5 (7) Nov 09, 2018
BTW, likely wasted on trolls, but I just had time to watch Svante Pääbo's 2018 lecture with his latest overview on hominid evolution. It is a very simple and transparent walk through of the genetic and biogeographical evidence (with the fossil evidence implied) of shared ancestry and how it is observed. This - again - goes towards showing that the basis for biology is an observational science, why it is repeatable and why it is successful at large.

Highly recommended for all, told by an expert with terrific presence to boot.

https://www.youtu...8yrEGAgw
A Neanderthal Perspective on Human Origins with Svante Pääbo - 2018
FredJose
1 / 5 (3) Nov 12, 2018
@Stumpy, from Old_c_Code:
A big question is why evolution occurs in quick spurts of time? i.e. many many new species arise in a very short geological time, repeatedly.


See here, Old Stumpy, is precisely why your definition of evolution is as leaky as a sieve.
Speciation is equated with darwinian evolution.

You cannot escape the issue by pointing me to your so-called rigorous definition of evolution.
It just doesn't work in real life.

There is absolutely no way (biochemically and genetically speaking) for new specified and required information to arise by random mutations and natural selection.

You can preach all you want and proselytize and gain as many disciples as you will, but it will still not turn a fable into fact.
In the end the only thing that matters is whether you believe in and accept one and only Creator as Lord and Saviour. And you don't have to go by blind faith, you can base you faith on facts that stand up to scrutiny.
SCVGoodToGo
5 / 5 (4) Nov 12, 2018
There is absolutely no way (biochemically and genetically speaking) for new specified and required information to arise by random mutations and natural selection.

[citation needed]

Quickest way to spot a lie or non-arguement is to look for absolutes.

In the end the only thing that matters is whether you believe in and accept one and only Creator as Lord and Saviour.


Fred, no matter how hard you believe, you cannot take your tome of babble written by neurosyphilis infested sheep herders (which has been rewritten many times by feudal lords to suit their needs) and turn fable into fact. Besides, doesn't your good book say something about thou shall not lie?

Go be pious somewhere else.
antialias_physorg
5 / 5 (4) Nov 12, 2018
Besides, doesn't your good book say something about thou shall not lie?

Unfortunately it doesn't say "thou shalt not be crazy".

Religion/belief is just state sanctioned insanity.
TheGhostofOtto1923
5 / 5 (3) Nov 12, 2018
citation needed
Heres a few:

"Gen1:1 "In the beginning, God created the heavens and the earth."

"Rom1:19-20 "For what can be known about God is plain to them, because God has shown it to them. For his invisible attributes, namely, his eternal power and divine nature, have been clearly perceived, ever since the creation of the world, in the things that have been made. So they are without excuse."

"Gen1:26-27 "Then God said, "Let us make man in our image, after our likeness." [Obviously god is a tool/weapon user]

"Jon1:1-3 "In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things were made through him, and without him was not any thing made that was made."

Etc.
And you don't have to go by blind faith, you can base you faith on facts that stand up to scrutiny
The quotes I listed are what fred means by 'facts'.

Plus genuine delusions and hallucinations experienced by godders.
Captain Stumpy
5 / 5 (3) Nov 12, 2018
@illiterate fred
It just doesn't work in real life
except that real life has repeatedly proven you wrong time and time again - like those references I presented that demonstrated evolution in action (Lenski, Extravour, Whittaker, etc)
There is absolutely no way (biochemically and genetically speaking) fo blah blah blah lies blah
see: previous sentence in this post
You can preach all you want blah lie blah
you're the one proselytizing here, promoting a lie that is demonstrably false
In the end the only thing that matters is whether you believe in and accept one and only Creator as Lord and Saviour
doesn't everyone believe in the Flying Spaghetti Monster?
I totally accept his noodly-ness, FSM be praised!
https://images-cd...700b.jpg

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