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Janet

Janet

Parsimony

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I remember the first time I heard that word.

Parsimony.

It was about my second year of graduate school.

It only took me two years to realize that I was inept in molecular biology lab (a dash of this and a pinch of that, which is the way I cook, does not work when you are  working in moles). So I moved to computers. Sort of. Brilliant choice since I had less training in computer languages and programming than I did in Biology wet labs.

It takes a lot to deter me and I hate failure.

Specifically I went into bioinformatics, the discipline that uses computer prowess to analyze masses of field and lab generated data.

The gold mine for people like me is genetic data (DNA). Strings of A’s, G’s, C’s and T’s (those are molecules, very interesting ones. We call them nucleotides) that depending upon the order in which they are found, carry all the information that tells the cell how to work. They are a fingerprint or a blueprint or  a map of that particular organism. Every living thing on the planet has a different map but all of them are made with the same alphabet of molecules in their DNA.

Being an evolutionist, Darwinian, you must make an assumption and that is that all of life on the planet is related. Most of the analyses I was doing were attempts to understand how organisms or pieces of their genetic material had changed over time due to the relatedness of us all.

Being an evolutionist, the assumption is that accumulating changes are sort of like a clock. They happen at regular intervals or not so regular intervals, but regardless of how accurate the clock, the more you have, the more time has passed. The tricky part is that you are looking back in time by only looking at things that are currently here. Think Extant.

The ideal thing is to find a theory that seems to make the most sense of your data. Explains the data. Makes sense.

And this is where parsimony comes in.

Lots of real computer scientists got on the bioinformatics bandwagon and started writing algorithms that were based on various theories that might best explain genetic data.

For instance: you could analyze your data based on the Unweighted Pair Group Method with Arithmetic Mean. UPGMA for short.Basically a this-is-most-like-this-so-let’s-cluster-those together.

I know. It sounded like it was going to be way more interesting than it is.

Then there was maximum liklihood.

This is statistics on steroids. It’s all about probabilities. Maximum ones.

It takes forever to run. Days. In computer language we would call that intensive. If UPGMA runs in about 20 seconds, no matter how much data you plug into it, you could watch Maximum Liklihood scroll through it’s progress over weeks. Long, endless weeks.

A Goldilocks dichotomy if there ever was one.

And then there was parsimony.

Parsimony. It was just right.

Parsimony meant that in nature, if you had to go from point A to point B, you’d go there the fastest way possible.

Sort of like this: If I wanted to go to Little Rock, Arkansas leaving my house in Houston, I would not head up to New York, then cross over to Colorado Springs, finally heading back down to Arkansas. I’d just go through Texarkana. That would be the most parsimonious route.

To apply it to evolution, if a string of DNA has one ordered set of A’s, C’s, G’s, and T’s, then to find the relationship between it to another set of A’s, C’s, G’s, and T’s you would assume that evolution, albeit a random process, would take the route of the least amount of mutations to get there.

I loved running parsimony programs.

Frankly, I was the Queen of Parsimony Reconstruction.

Until a couple of days ago.

W., a friend of mine, who loves to argue evolutionary theory brought up something that made me think he needed an introductory lesson into the concept of parsimony.

Having a different background than mine, W. stated what he knew what the word meant.

“Look up parsimonious tipper,” he demanded, righteousness dripping all over his command.

I must say, if W. wasn’t fun to argue with, I might not have acquiesced. There are times when I value stubbornness over logic. And my sense is that although I have never actually caught W. in the act, I have convinced myself I need to be wary that he  might just believe in the value of employing red herrings. Because W. likes to win as much as I do.

Okay there is another reason. W. is wickedly smart and I thought I just may have found him in error.

I long to do that.

I long to know just once, more than he does.

Let’s face it, I pretty much knew there was all there was to know about parsimony. I understood all its nuance.

“Just Google it, unless your Dell can’t handle that.”

We also have a standing argument over personal computer operating systems, that at least for me has gone long past reason.

Sure enough. There it was. Just as W. had explained the word in the way he had become acquainted with it. To W. it carried the connotation of ‘stingy’.

I could probably say, what is the stingiest way to get from Houston to Little Rock and you would have understood the most parsimonious route, but stingy also carries a little negative vibe to it that I really wouldn’t want to convey if I was writing a paper to the Journal of International Systemic Biology. (Heck no, I heard you say, how obvious it is that one wouldn’t want to do that.)

Here’s my point: whether your analyzing DNA data to consider the theory of evolution, figuring out how much you should tip, or figuring out why the church you grew up in holds to the theology it does, wanting to understand why the world is the way it is, from the standpoint of science or soul, truth is important. And truth is not about finding an answer and then never, ever reconsidering what you thought you knew.

We are wonderful creatures, we humans. We have wonderful brains bounded by hearts that the capacity for thinking and understanding. We are meant to do that individually and collectively.

I hope you are surrounded with good, like minded people who make you think and that when given the opportunity, whether its serious or simple, you do.

It is the glory of God to conceal things, but the glory of kings is to search things out. Prov 25:2

 

 

 

 

 

 

 

 

 

 

 

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