To over simplify this conversation and in response to Evan, there is no way to refute something that has been established as fact.

In biology, we consider evolution to be a theory--which has similar meaning across disciplines. So evolution is a well established principle supported by an enormous amount of empirical observation and experimentation.

Under the overarching "theory of evolution", we have established a number of "evolutionary processes" which can be generally thought of as mechanisms of change (e.g. mutation, genetic drift, natural selection, sexual selection...). These processes/mechanisms have been historically framed as testable hypotheses. We know that these processes are real and are happening around us, but they can work in conjunction or isolation, they can promote directional change, or be in opposition. So taken individually, these evolutionary processes can be supported or refuted within or among populations--however, it's important to note that refuting the role of one of these processes in a study does not refute the theory of evolution, it simply implies that another process or set of processes can be invoked and tested.

Our ability to test these evolutionary processes has change alongside advances in technology. As genomic techniques continue to burgeon, we find that past hypotheses regarding evolutionary processes and genetic heritability were over-simplified. These over simplification raised false problems, such as "missing heritability" invoked by Evan (see this paper for detailed explanation: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831613/). We now know, from empirical testing, that many traits rise from complex genetic architecture and similar traits can have quite different genetic underpinnings. So evolutionary biology remains a vibrant, developing, and exciting field of study, but evolution remains firmly established as a tenant.

Thanks a lot Evans.

To over simplify this conversation and in response to Evan, there is no way to refute something that has been established as fact.

In biology, we consider evolution to be a theory--which has similar meaning across disciplines. So evolution is a well established principle supported by an enormous amount of empirical observation and experimentation.

Under the overarching "theory of evolution", we have established a number of "evolutionary processes" which can be generally thought of as mechanisms of change (e.g. mutation, genetic drift, natural selection, sexual selection...). These processes/mechanisms have been historically framed as testable hypotheses. We know that these processes are real and are happening around us, but they can work in conjunction or isolation, they can promote directional change, or be in opposition. So taken individually, these evolutionary processes can be supported or refuted within or among populations--however, it's important to note that refuting the role of one of these processes in a study does not refute the theory of evolution, it simply implies that another process or set of processes can be invoked and tested.

Our ability to test these evolutionary processes has change alongside advances in technology. As genomic techniques continue to burgeon, we find that past hypotheses regarding evolutionary processes and genetic heritability were over-simplified. These over simplification raised false problems, such as "missing heritability" invoked by Evan (see this paper for detailed explanation: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831613/). We now know, from empirical testing, that many traits rise from complex genetic architecture and similar traits can have quite different genetic underpinnings. So evolutionary biology remains a vibrant, developing, and exciting field of study, but evolution remains firmly established as a tenant.

The strongest proponent of the "falsificationism" was one of the first in answer this question, but historically there are two answer. i leave you this abstract where you can read the reason of the Falsifiability of the Evolutionary theory sensu Popper

http://www.informationphilosopher.com/solutions/philosophers/popper/natural_selection_and_the_emergence_of_mind.html

Yes it is. If you find fossil rabbits in strata of Precambrian age then you have falsified the theory of evolution. Thank you, JBS Haldane.

"there is no way to refute something that has been established as fact."

Just to clarify, this is, again, an admission that evolution, as currently posed, is NOT falsifiable. That is NOT a good thing.

EVERY single day, all the basic laws of physics, from g to G to the arcseconds of mercury predicted by general relativity, are falsifiable. Thus it is awesome that they remain true (as per Popper). It is not true for evolution, because fitness does not have units. It does not pass tests when it is tested. And the head of the NIH doesn't even believe evolution, but a variant called "biologos". Since he is where we spend most of our money (why does religion have to be in harmony with evolution? eh, I guess we'll get to that with the next $100B)... I'd say all of biology currently exists on the premise of an unfalsifiable theory that has been proven false by the missing heritability. Theories including culture do not miss such heritability, and Francis Collins pays lip service to as much... but never dollar service.

Jesus LOVES science! BIOLOGOS! Or at least... if you want an NIH grant, you probably better toe that line. But sure, evolution is established as fact, N1 Scott!

When something "becomes established as fact", but "there is no way to refute" it... we've trapped ourselves in a circular word hole, from which we may never dig out. I'd encourage biologists who are upset to, instead, formalize the theory of evolution, make it falsifiable. Then you can answer this question with a link and pride, instead of a bunch of wiggle words.

Thanks, Evan. It take courage to put it like this.

Evolution is not only falsifiable, it is also directly observable. We can see mutations happen (for instance in viruses, which are fast-evolving), we understand the mechanisms by which mutations become fixed in populations, and we are able to reconstruct phylogenies with some precision that show the timing of these mutations. There is absolutely no need to go via the concept of fitness to show that evolution is a fact.

That's quite a rant, and a rather semantical one. Human descriptions of processes and effects are dynamic and falsifiable. To say that gravity is a fact does not mean we can't alter they way we calculate it's effect and properties, nor does it mean that we can't falsify aspects of theory linked to gravity--but in the end, the effect we experience from gravity is still real, factual, and operating on all of us here on Earth now, in the past, and the foreseeable natural future.

Unlike gravity, evolution is not a law--not all living things have to currently be evolving, but evolution is established as a robust, empirically demonstrated principle. Evolution within extant species, populations, locations, or study time frames can be falsified. But as I said before, that does not falsify the THEORY of EVOLUTION in the big sense. The simple status of not knowing how much certain traits measured at a population level are influenced by genes vs environment vs gene X environment interactions (which is at the heart of the missing heritability argument) does not falsify evolution as a process, it simply points out that we still have lots to learn and what we learn might change the ways we model evolutionary processes.

Feel free to approach funding agencies and grant proposals however you choose, that's a personal decision and not one I plan to discuss in any greater detail on a scientific social network.

Evans, your response just shows that you don't really understand how evolution works. The possibility, as Bjorn suggested, of finding fossils in places inconsistent with evolutionary predictions would itself falsify the theory (in the "big sense," as you call it). Evolutionary biologists don't refuse to accept "alternative theories to neoDarwinism," it's just that no tenable alternative theories are proposed.

Also, it's probably best to reserve terms like GTFO and bullsh** to non-professional fora.

But whats the difference between principle and law. There is too much ambiguity for a serious debate

I don't think repeating bullet points drawn from the creationist playbook for spreading doubt about evolution constitutes informed dissent. But if you think of yourself as an important voice and want to debate these topics, put in an abstract to speak at the Evolution meetings or the Ecological Society of America meetings the next time around. Or write a position piece for one of their journals. But you can expect to have your points debated by an audience of very informed evolutionists in those forums and they will expect very basic professionalism in tone and language.

This will be my last post, and you can feel free to declare yourself victorious is that is desirable, but I will respond one more time to your objection of me saying evolution is a fact (and in this area I may respectfully disagree with some colleagues). We've seen evolution happen, we can measure it happening and determine mechanisms at play, and we can force evolution to happen in experiments so I used the common, colloquial term "fact" to explain why we don't spend our days trying to falsify evolution. To argue that something we've seen and know to happen is not factual is your choice, but it amounts to arguing that biogeochemistry is not a science because it doesn't seek to regularly falsify or allow for the falsification of the complex processes we know to drive the nitrogen cycle.

We will always be learning and updating our understanding of complex processes, and we may find out that other important mechanisms or processes are important influences or considerations, but when we know something exists, know that it is happening, and that it can be measured it is reasonable to study that thing without having to continually justify our knowledge of its existence.