Wednesday, June 6, 2012

I don't get people who deny common descent

Random thought here: The evidence for evolution is overwhelming, but you do actually have to educate yourself about some of that evidence. You can't just look out your window and deduce, say, some of the really striking evidence coming from molecular biology that is helping to clarify the tree (er, tree-ish, allowing for horizontal gene transfer) of life.

But the evidence for common descent? I mean, are you kidding me? First of all, anybody who denies that humans are a type of ape, I mean.. Really?!? Have you, you know, like looked at a chimp or an orangutan or anything? You didn't notice that they look almost exactly like us? Second of all, the Satan is a Dick Theory notwithstanding, the frikkin' fossil record... I mean, I guess I can understand this one because many Creationists studiously avoid ever acknowledging the incredible wealth of transitional fossils that are constantly being paraded in the media as the latest example of "The" missing link. But come on...

That such incredible change could have taken place through natural selection and genetic drift alone, that's hard to comprehend, I get that. A lot of that I think is because our ability to conceive of the time scales involved is very poor (I have found that when thinking about big numbers, there's a point where I start treating exponential growth as if it were linear, e.g. I have a tendency to think that the order of magnitude difference between 10,000 and 24,000 is on par with the difference between 10110 vs. 10124, but of course that's absurd -- and I know how absurd that is, and yet that's still how I think about very big numbers instinctively, so imagine how bad it is for someone who is less familiar with large quantities). But in any case, if somebody accept common descent, but thinks there needed to be some kind of outside force to help natural selection along... well, they're still wrong three ways from Sunday, but that's a mental error I can grok. You have to actually look for the evidence to understand what is wrong with that argument.

But denial of common descent? Denial that we are, plain as day, primates? Don't get it.


  1. For big numbers such as comparing 10^110 and 10^124, I must think in terms of logarithms. By systematizing the mental process involved, translating back from logs to raw numbers etc, the big numbers can become surprisingly familiar and intuitive. I think we just need to teach the creationists logarithms. :)

    SIDEBAR: This works so well that I can even feel (relatively) comfortable with numbers such as 10^10^120. For example: Let's call A = 10^10^120. Then A*10^5000 == A, because 10^120 + 5000 == 10^120. So if the universe were 10^10^15 millenia old, it would also be 10^10^15 nanoseconds old. Ha. :) Add a third exponentiation though, and the process is just too meta for me to fully grok. My mental recursion depth is only n=2 for intuition purposes.

    Anyway, denial. I think the only answer is that the evidence has nothing to do with it - those minds have been made up, end of story. Which of course should not come as much of a surprise.

  2. Of course when I say 'equals' above, I am talking about to the nearest sig fig in the argument. I assume that's obvious, but I said a few ludicrously false things otherwise so perhaps worth pointing out. And I apologize for the tangent, but who can resist mentioning this case where units do not matter.

    In any case, I would back down from my ludicrously false claims when someone explains why I am wrong, rather than putting my fingers in my ears and yelling louder. Unlike certain people with opinions on certain theories of biology.

  3. I find thinking of it with logarithms, while it makes the numbers easier to work with, is actually even worse when it comes to an intuitive sense of magnitude. Now you have the quantitative difference between 10,000 and 10 being just "3".

    You just blew my mind with this, though:

    So if the universe were 10^10^15 millenia old, it would also be 10^10^15 nanoseconds old.

    Woah. That was some serious mental jujitsu you just pulled right there...!

  4. I am talking about to the nearest sig fig in the argument. I assume that's obvious

    Yes, I understood what you meant :) I had to read the paragraph twice, but I got it. Neat trick!