I hear that question posed from time to time. Sometimes it is directed at me, but more often I hear it directed towards established (and often famous) scientists. It’s usually a product of creationist rhetoric where the answer doesn’t really matter. Regardless, it is an interesting question.
What would change my view on evolution?
It depends what is meant by “change”. My view on evolution changes quite frequently, actually. Sometimes it’s a qualitative change: the relationships between our known ancestral cousins are always shifting ever so slightly. Often, there is little consensus about where to place certain members of the genus Homo on the evolutionary tree. As new evidence is found, as more research is done, as further facts come to light, my views are always changing on that aspect of evolution.
And then there are quantitative changes. One excellent example comes from the discovery of tetrapod footprints. That discovery pushed the evolution of tetrapods back about 18 million years. All the relationships between species of that general time period stayed the same, but our view of when tetrapods began to populate the land changed.
And then there are all sorts of other changes, like recently when it was shown that natural selection works differently on allele fixation in sexually reproducing populations versus more simple asexual populations. (That was also a qualitative change, but on the genetic, not taxonomic, level.)
So if that is what is meant by “change”, then there are all sorts of examples that show how my views on evolution are, well, evolving. The same can be said of biologists around the world. But what if by “change”, the real question being asked is, What would make me dismiss evolution? Then the answer is very different.
As I recently explained, a basic fact of science is that it does not tend to operate on individual studies. It requires a body of evidence to change views. For example, I reject a connection between cell phone use and cancer. Studies have shown possible links, but they have been far from conclusive, weak even. And more importantly, there is a body of evidence showing no significant link. I’m going with the evidence in bulk, not the individual packaging. This relates directly to the question of what it would take to get me to dismiss evolution because there is a famous quote by J.B.S. Haldane I had in mind when starting this post. When asked what it would take to change his mind, he retorted,
Fossil rabbits in the Precambrian.
But that wouldn’t change my mind. My very first suspicion would be fraud; I suspect little more from creationists (and we know how much they would be promoting such a discovery). But let’s say it came from a reputable research team, then what? I would admittedly be perplexed. There is no reason a fossil rabbit ought to be found in that era, but that doesn’t mean we get to throw out such a well established theory as evolution. We know evolution is true insomuch as we know gravity is true. It would necessarily take more than a few rabbit fossils to alter the unifying theory of biology, just as it would take more than an apple falling up for us to alter the theory of gravity. Even if we could never explain the fossils satisfactorily, I would have no doubts that evolution still formed the basis of my field of choice.
What would change my view would be the discovery of a number of fossils in all the wrong places. We would need to start finding mammals and birds dating back 800 million years; we would need to see dinosaur fossils embedded in the rocks of 20 million years ago; we would, yes, need to see rabbit fossils in the Precambrian. No, I don’t need these specific examples, but I do need these sort of examples. I don’t want just individual anomalies that fly in the face of modern theories. I need more than that: it takes a body of evidence to start changing my view. Because that’s how science works.
Filed under: Evolution | Tagged: Allele fixation, Evolution, Fossil rabbits, J.B.S. Haldane, Precambrian, Tetrapods |
For the Sake of Science 
Evolution is not a ‘view’. It is a collection of scientific observations, coupled with predictions and developed theories in a dozen separate disciplines.
Asking what will change a view of evolution is equivalent of asking what will change your view of gravity or what will change your view of the Pythagorean theorem.
Ask 10 different biologists about evolution you will likely get 10 different “views”.
I thought science was rather organic in that it constantly evolves. Is that not true?
Evolution is not a law, not in the way that gravity and many mathematical principles are. Thus it does have a lot of interpretation that needs doing. We know it happens and we are far from a definitive answer on how and why and how long. There’s a lot left to be done.
As far as finding fossils in the wrong places… It happens all the time. The Earth is not static, the ground shifts and buckles and mud slides etc etc. AND it always has. It messes everything up whether its 80 million years ago, 260 million years ago or 2600 years ago.
There is a shitload of care and cautiousness that has to go into dating fossils and artifacts, it doesn’t mean its fraud most of the time. It means you are missing a piece of the puzzle, perhaps a geological event, perhaps the overlooked evolution of a mammaly rabbity creature that died out only to have a similar species come about later down the line, independently.
Nate, you are such a negative person. There is one hundred thousand positive things for each negative thing you gen up. The evidence is overwhelming.
Gravity is a theory, not a law.
There is no differing ‘views’ on evolution by biologists, only disagreements on the details of how it works, not whether it works. That is just nonsense brought up by people who really have no case to make.
I’m glad you think I’m negative, what does that make you I wonder? Certainly not a positive person, not with the number of negative comments you make.
I would suppose you are right about gravity, the mechanism is still a big ?, it just “is”.
And that’s exactly what I was talking about, the hows, the whys and the how longs.
Then religion has absolutely nothing going for it. Why is anyone a believer? How can anyone have any thoughts on any gods when there is absolutely nothing? Zilch, Nada.
There is as much evidence of Jupiter as there is for Jesus.
People who subscribe to that nonsense have no standing when it comes to doubt and skepticism. Just laugh at them and move on, I guess…LOL
I’m not even sure what you’re talking about now. It’s too early for this. Also too early for “LOL’s”.
Much, many coffee beans must be sacrificed now.
Michael: A thoughtful post pointing up a fundamental issue about how science works. Even the largest body of evidence can lead to only provisional scientific conclusions. The bigger and more consistent the body of evidence is, the stonger the conclusions are, but there is never 100% certainty about any particular assertion.
As for Nate’s claim that finding fossils in the wrong place “happens all the time”, I doubt that this is true in the “pre-cambrian rabbit” sense. (Also, what is the frequency of “all the time?”) Things do get messy, given the vagaries of fossilzation and geological change, but I am not aware of any genuine anomolies in the sense of the examples that Michael lists.
So, it is extremely improbable that there will ever be enough evidence produced to “change my view” of evolution, if the meaning is that I would be convinced that lineages of living beings do not change over time in response to physical genetic and environmental processes, or that all (or almost all) currently living things ultimately share a common ancestor. The chance of such a body of evidence (or a theoretical explanation of the existing evidence) being discovered that would overturn our understanding of evolution (in this broad sense) may not be zero, but it is so vanishingly small that it would be perverse to think that such a shift has any practical likelihood of happening.
Tom, you are correct, Nate is very wrong. The only time this happens is when many layers get heaved up and turned on its side or turned over, and this is usually obvious by looking at the layers and dating them.
I don’t mean all the time in the sense that one can expect to see this on a regular basis.
I mean that it is not out of the ordinary. It’s not a special occurrence.
And you’re somewhat right, Bob. It’s not always apparent. I only meant to make the point that even finding things out of place isn’t necessarily something that should give anyone concern and
Tom, you are likely right about any usual geological event being responsible for moving something to the Precambrian layers. That would be a pretty radical shift. Usually things are brought forward, not back. And we have issues of trying to figure out where it came from, not whether on not it belongs where it was found. It’s apparent when there has been upheaval of some kind, Bob gives a very rare example of neat delineation of messed up strata.
Nice to see you still care enough to jump on me and start punching like I brought your daughter home late from the prom, Bob. As always it means a lot.
Poor and incorrect statements call for corrections. I can’t help it if you have way more than your share of poor and incorrect statements, Nate.
If you say so Bob.
Thoughts:
Quibbles over “view” do hold importance when we mean to clarify our terms; we don’t want anyone thinking we meaning something like “perspective dependent upon circumstances”. But regardless, I see it as a quibble. PZ had a post on this general idea, but he titled it something odd like “PEEEDAAAANTS”, so it’s impossible to find it in a quick search.
There is no scientifically defined difference between a theory and a law. They both can be used interchangeably (less we go out of our way to create our own definitions of how we are using them). Scientists have a habit of creating informal convention that often gets misinterpreted by the general public (see Einstein’s use of “God”).
I consider fossils as being found in unexpected strata when they are identified as coming from a strange stratum. As Tom pointed out, this doesn’t happen in the Precambrian rabbit sense.
A wonderful example of evolution:
http://www.wired.com/wiredscience/2011/01/pneumonia-superbug-antibiotics
This eliminates any reasonable doubt.