We accumulate mutations generation after generation. If we have been here for hundreds of thousands of years then we would have gone extinct long ago. If we add the mutations that we would have inherited from our non-human ancestors then the problem is even bigger.
Harmful mutations are culled away by natural selection. You’re here because the mutations carried by your particular ancestors were not the sort that prevented them from reproducing. So, yes. You’ve got loads of accumulated mutations in you, including the broken vitamin C mutation (a bad one, but you have dietary options that prevent it from being fatal), as well as the lactose digestion mutation (a good one that allows you to drink milk unless you are from certain populations that can’t). And you would have many other mutations as well that have no effect whatsoever on you.
You seem to be saying that all harmful mutations are culled away by natural selection. Do you really believe that?
Not all mutations are detrimental. Whether or not a mutation is beneficial depends a lot on one’s environment.
How do you figure? Or rather what evidence do you have to support your idea beyond your own common sense or intuition?
There’s a simple comparison one can do that tells us yes indeed such random mutations are responsible for part of the genetic diversity among humans and among humans and our most recent common ancestors-
It’s not just a case of believing it. There are a lot of computer algorithms that operate on that basis. Evolutionary algorithms have proven themselves to be very successful in artificial intelligence and machine learning, for starters.
No. My opening sentence should have included the qualifier that if they are harmful enough, they are culled away by natural selection. The vitamin C example is obviously a harmful mutation that has not prevented many of us from reproducing successfully.
[so the key word in your restatement is the word “all”. My statement left that as an implied possibility. But what I meant instead was “some”, or “the ones serious enough to disable…”.]
‘How do you figure? Or rather what evidence do you have to support your idea beyond your own common sense or intuition?’ Geneticists accept (correct me if I’m wrong) that we accumulate mutations, generation upon generation. If this is true, and if natural selection only removes some of them, then how come we are still here after hundreds of thousands (or millions) of years?
What do you mean “still here”? We weren’t here at all hundreds of thousands of years ago, nor even was anybody that was here then remotely like us. It’s those very mutations that help explain why we’re here now at all as we are! They are yet another amazing component of God’s creative toolbox.
By saying “some or the ones serious enough to disable” I assume you are accepting that some of the mutations that are passed on are in fact harmful to some degree. My point is, how long could the accumulation of such mutations (those that just make it under the radar, so to speak) occur before the organism becomes extinct?
Yes I know. The link that I sent you, not sure if you took a glance at it - is a nice demonstration that the single nucleotide difference among humans are caused by random mutations. Yet the pattern matches quite nicely with the single nucleotide difference between humans and chimpanzees- just there are more of them.
As I said, evolutionary algorithms in computer science, software engineering and artificial intelligence work on the basis of these principles.
Well … many have become extinct. We obviously are descended from those lines which did not [yet]. There is an interplay between mutations (those that even have any effect at all) and a changing environment. So what may be a harmful mutation in one time or place, may be a helpful one elsewhere. So it isn’t so simple as a binary sorting into “good ones” and “bad ones”. Others with deeper biological [genetics] background and training could give a more specific answer to your question, probably. But I think I’m safe with the generalization that it is not accurate to see “accumulated mutational load” as some downward trajectory from some original pristine form. It is rather an accumulation of changes - some deleterious, many with no noticeable effect at all, and some turning out to be adaptive to present circumstances.
So I guess what I’m claiming is that the “mutation load = net bad” formula fails to capture an accurate [or complete] picture of what we understand of history.
‘What do you mean still here?’ I’m not talking about you and me I’m talking about our ancestors who presumably had mutations that they passed onto us. It’s not an issue of whether they looked like we do today, it’s the fact that if they really were our ancestors then we have inherited their mutations. You say it’s an amazing component of God’s creative tool box, but genetic diseases make people’s lives a misery and cancerous tumours in children does not sound like an idea from a loving God.
Yes I did look at it. But what has it got to do with the accumulation of harmful mutations generation upon generation?
Hi, I think you answering someone else’s point not mine.
Sorry, you’re right. I missed that you were quoting @pevaquark.
Just a bit of advice here: if you want to quote someone, select the part of their post that you want to quote, then click on the “Quote” button that appears above your selection. It will automatically insert their quote into your reply in the distinctive way that you see in everybody else’s posts.
It’s true that not all mutations are detrimental. The fact that there are tuskless elephants will, I hope, ensure the survival of these magnificent creatures. This is not evolution in the sense of new information but it still helps. But the question I have is how can we accumulate mutations, generation after generation, over long periods of time, and still be here. Natural selection removes some, but not all, harmful mutations. However, there are plenty of others that slip through the net.
I gathered as much. I was speaking representationally (non-literally) - as in thinking of our ancestors as being people pretty much just like us - early “versions of us”, so to speak. And I was just suggesting that they were not in fact like us (if we go back on the time scales you mentioned), but that the very mutational accumulations we are discussing here are some of the very things that helped change them into you and me.
You are right about that! And when it is bad enough, those genes don’t get passed on.
We all struggle with that. Nobody really escapes the theodicy juggernaut. We just learn to live with it (or not). Acceptance or rejection of evolutionary biology does not rescue the Christian from this struggle.
I would add this, though. For those who see physical survival / and or successful reproduction as the “final measuring stick” of justice or cruelty, scriptures tell us a different narrative. Jesus was the best human being ever to walk this dusty globe, and he died suffering and childless (in a mere biological view of things). And yet he now has added more children to God’s family than anybody ever! So things that are cruel, unjust, and despicable on the measuring sticks of this physical life don’t get the last word! Thank God for that. The child that survives only a few years and then dies young because of a cancerous tumor ends up being a loved and valued member of God’s kingdom who may have spread much love in the world while here. Still don’t wish it on anyone, and it’s still an agony to be sure. We fight against it, and rightly so. We also learn to trust God - eventually.
BTW, if there are specific sentences others have written that you wish to include as a quote in your own post so you can show your direct response to it, just select the portion of interest in the other person’s post, and click on the grey ‘quote’ box that pops up. That inserts it as a quotation into any reply that you already have open (or it will create a new reply for you if you haven’t started one yet.)