In many cases, I do think facts have no effect.
I completely disagree. The basic concepts are much easier to understand than the specifics. For example, it is easy to see how natural selection affects coat color in mice in different environments:
It is quite difficult to explain how mutations in the melanocortin-1 receptor can change paracrine stimulation within the the melacortin axis, and why mc1r is just one target for the pathway:
I think you are exaggerating here. Symbiosis may present a challenge in the eyes of laypeople who (i) understand symbiosis, (ii) donāt understand evolution, (iii) donāt believe biologists. But thatās far from all of them.
For clarity, I think of myself as a layman.
Right you are. But thatās not what Iām talking about. Iām saying that Jerry Coyne presented a potential evolutionary pathway as a plausible explanation for a symbiotic relationship. I never suggested that it would be easy to understand (or explain) the technical aspects of such a relationship. What I said was that if the evolutionary pathway was backed up by data (i.e. wasps with A mutation in allele X would be more likely to consume spider organ Z than those wasps without A mutation in allele X) it would be more readily accepted by people who are otherwise prone to also misunderstand the issue to begin with. As it is now, the pathway is merely suggested, not confirmed.
To use your example, I (as you correctly supposed) have no idea what the flowchart posted above means. But I know that it signifies that you know how the color change occurs and I can accept that. This is what I was proposing (@John_Harshman) be provided to show, similarly, how a larval wasp might prefer one spider organ over another.
Yes, good points. i = I think everyone who makes this complaint has some idea of what symbiosis is. ii = I disagree. Whether you understand evolution or not, you are more confident in a suggested solution if it is backed up by data like a peer-reviewed study. iii = anyone who doesnāt believe what biologists say isnāt going to be impressed by data. That goes without saying. If Iām talking about color-blind people, Iām not going to include the blind in the conversation.
Why are you hung up on this point anyhow? If Jerry Coyne took up the conversation, he must think that the issue of symbiosis is serious enough to discuss. Sure, not every layperson sees it as an obstacle. When I said āallā I didnāt mean each named person. I meant that the population was significant.
In my eyes, it still boils down to a very general and simplistic explanation for symbiosis. It is quite obvious to me that the behavior of the modern species is driven by genetics since learning is not something these larvae can do. Since it is driven by genetics it becomes quite obvious that this behavior can be changed by mutations and selection. Without even knowing the specific alleles or mutations involved, it should be obvious that the system is open to evolution.
If only that were true.
I actually agree with you. It is first of all a totally legitimate question to ask, āhow could X evolveā?
We are all ignorant about something, and because of that ignorance there are things that will appear implausible or even incomprehensible to us. Thereās nothing wrong with asking questions about things we donāt know and donāt understand.
To someone who is not a biologist, and who has no training in evolution or molecular biology, it is perhaps completely normal to have a sort of intuitive incredulity about how evolution could even occur, or that there ājust so happens to beā different genetic predispositions towards preferring or rejecting certain tastes.
But then one could of course ask out of genuine curiosity, why do biologists think something like this could evolve?
As long as we note thereās a difference between asking this question out of genuine interest and in honest ignorance of the answer, and asking it rhetorically, as if any putative answer given should be considered intrinsically implausible, if not impossible.
At best, it is certainly no defense against the original question. Granted, one asked āhow could this happenā and another answered, āhereās how.ā But the response is still a guess without data. Find a gene that switches the āspider organ taste preferenceā from one organ to another and you have a viable response to the challenge.
This is where I donāt agree, because Iād actually say that if you know enough molecular biology, for example understanding the genetics of taste receptors, and the fact that different types of tissues have different molecular components, leads to the expectation that they should have different tastes, and all animals have numerous different taste receptors that respond to different compounds.
I donāt think we actually have to bother to go and find the gene(s) responsible to have good reason to think the question doesnāt constitute the sort of challenge imagined by the creationist posing it. I think we know enough molecular biology already, to be able to say with considerable confidence, that this is the sort of thing weād expect there to be.
Even without knowing any of that, I know from my own experience that eating different meats, including organs, that they can have wildly different tastes. Domestic pig liver is famously disliked by many people(I happen to like it though).
Thanks and I really appreciate your reply.
But, if you do know and you can show how, donāt you think it would constitute and even stronger answer? This is the sole point I was making. Iām not asking anyone to go perform this experiment. I simply said that it would be great if there was a study that showed the genetics behind this for some āiconā of symbiosis. I donāt see that itās even worth disagreeing about. But twenty-eight posts laterā¦ 
Again, thanks, I appreciate your thoughtful response Mikkel.
From the letter asking how the following intricate symbiosis could possibly evolveā¦
āThen we have another question: how does the larval wasp, when hatched, know to eat only non-essential parts of the paralyzed spider, in order to keep it alive until it can pupate and become a living, flying wasp? For it certainly eats everything except the vital organs, leaving the best ātil last, when it can gnaw its way to freedom and spread its wings to find a mate and then go spider-hunting.ā
Can the author not see the problem with this apologetic? I cannot imagine a more macabre design being attributed to the direct creation of a loving God. Ecology is a web replete with death by tooth and claw, more terrible than wonderful. Did God author, by turn each organism and creature in detail, fang and stinger, to inflict and bear such suffering? This is supposed to support the notion of direct creation?
I will grant this - I find the argument incredulous.
Because when you point creationists toward such evidence, they do not acknowledge it. Those would constitute ignoring.
Such evidence? Is there such evidence? If so, this is what Iāve asked for this entire post. So if it exists, please point it out so that I can appreciate it in all of its data-ridden beauty. If not, then you cannot make this point, because this evidence does not exist to be ignored.
Do you need evidence for this specific case of symbiosis? If not, did you Google with incredibly obvious search terms like āgenetics symbiosisā?
I did, and I got a review (not evidence itself, but a pointer to a lot of evidence) of one of the best-studied cases:
Now, donāt take my word for it. Present this pointer to the evidence to a creationist and see if it is acknowledged or ignored.
Hahahaā¦ I do not need it, but I did not (obviously) Google those even-more-obvious terms. Good to know that the data I was asking about has been, in fact, published. Seems that some other human on the planet thought it was important enough to do so! Or all of the good topics were already taken.
Thanks very much, John. That wasnāt nearly as difficult as I had imagined!
They probably donāt even see that it is evidence. So they ignore it because it doesnāt fit their understanding (or misunderstanding) of how things work.
A relevant quotation from Darwin in regards to the theological implication of wasp behaviorā¦
With respect to the theological view of the question; this is always painful to me.ā I am bewildered.ā I had no intention to write atheistically. But I own that I cannot see, as plainly as others do, & as I shd wish to do, evidence of design & beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent & omnipotent God would have designedly created the IchneumonidƦ with the express intention of their feeding within the living bodies of caterpillars, or that a cat should play with mice.
This type of intricacy in nature does not speak to a benevolent God, and was a major stumbling block for Darwin.
I should point out that this forum favors the Christian view that God guides all creationā¦ whether by special miracles , or by using natural processes, like evolutionary processes!
No objection here.
Again, only the uninformed laypersons who already reject evolution would be likely to make arguments from incredulity. Those who do not already reject evolution might not make such an argument, but instead say something like āWow, thatās amazing!ā. .
Because heās seen it happen time after time after time, just as I have. Creationists being shown data and evidence and counterexamples to their claims who either concede the point or simply vanish, only to repeat their claims a few days later as if the previous conversation had never taken place.
For this particular topic, just look for any creationist who continues to claim that any genetic change that requires two or more mutations also requires those mutations to happen at the same time in the same organism.
They have no effect on some people. Thatās why such claims are called PRATTs - because they have literally been refuted thousands of times, yet creationists still repeat them.
Have you not seen [redacted] and [redacted] here being completely impervious to correction?
Thanks Roy. I see where you are coming from. Please know, that you, @Mercer and @John_Harshman, and many others are giving up too easily. You ask how I knowā¦ it is because I rejected evolution as recent as two years ago. Ask @Joel_Duff, heāll tell you. He got so tired of my questions, he pointed me here. I spent two years reading, asking, assimilating and comprehending. I have a huge stack of books from DI, which I consumed joyfully, thinking that they were the final word on evolution. So, all of you, stop going dark and giving up on people, assuming that they cannot and will not change. Sure, there are vocal proponents of every topicā¦ heck, how many times has āflat earthā come up recently? But because a proponent may never change his/her mind doesnāt mean that other readers wonāt. Giving up on them simply gives a greater reason to stay put.
That those people exist is NOT in question. That others who are reachable exist who are worthy of your efforts, even if they are frustrating, is what is important. People see when others are inflexible. Weāre all sensitive to that. The Bible says to āspeak the truth in loveā because that works. Just keep speaking the truth. Donāt waste time explaining why thereās no value in it. Thereās never no value in it, even though it may feel like it.
Hahahahaā¦ funny how names flash in my mind so easily when reading this. They will always be around and they may never change. But, again, thatās no reason to stop making good points. That was the entire purpose of my response to Jerry Coyneās article. Itās interesting, but wouldnāt it be more interesting if there were an example of a study tied to it? Yes, it would be! And it is (thanks @mercer).