I am fascinated with brain chemistry. If you ascribe to the philosophy that all we are is brain chemistry (there is nothing supernatural or soul-ish about us), then I guess you would attribute our differences, the personality that makes us each who we are, to the shaping of experiences through our lives. But I have to tell you. That doesn’t answer quite enough of the majesty of humanness, if you ask me. For me, there is much, much more to us than mere chemical synapses.
But, there is no getting around it, brain chemistry, just it alone, is incredible.
We’ve already talked about ‘brain washing‘. (As an insomniac, I now take a secret pleasure when I know I have spent enough time sleeping to have washed the chemicals fresh out of my head, starting the day with a clean brain so to speak.)
And then this week, three guys, Liran, Eran, and David from Hebrew University published a paper on human evolution, describing what they think must have happened about 600,000 years ago, give or take 50,000 or so. You might wonder how in the world can they know what happened that long ago? Where did they get their facts?!
They looked at DNA.
You know, DNA, the stuff in every living cell that hard codes what you are. Among other things, the stuff that tells what chemicals to make in your brain.
Here’s what they did: because we have dug up bones of skeletons we call Neanderthals and more skeletons that we call Denisovans, researchers have taken bits of the stuff left in their bones, isolated the DNA from it and sequenced it. Researchers have done this with a lot of things that are living, including us Homo sapiens. While researchers were doing this, other researchers were beginning to do other experiments on those old bones and started to realize that rather than a progression of ape like to more human like evolution, some of these skeleton bones were around the same time skeletons of homo sapiens (us) were.
In other words, they were our contemporaries, not our ancestors.
With all these comparisons, the current explanation is that not only were they our contemporaries, we were likely having sex with them.
And let me tell you, it was this Christian evolutionist that had poo pooed an idea of her favorite Bible teacher when he postulated some months back, that perhaps this verse in the Old Testament could be explained by interspecies breeding.
Genesis 6 When man began to multiply on the face of the land and daughters were born to them, 2 the sons of God saw that the daughters of man were attractive. And they took as their wives any they chose. 3 Then the Lord said, “My Spirit shall not abide in[a] man forever, for he is flesh: his days shall be 120 years.” 4 The Nephilim[b] were on the earth in those days, and also afterward, when the sons of God came in to the daughters of man and they bore children to them. These were the mighty men who were of old, the men of renown.
(Atheist, believers alike:It pays to consider everything you can when you want to know the truth.)
Back to DNA and comparisons.
Between Neanderthals, Denisovans, and us, our DNA is 99% similar. (Between us and chimpanzees, we are 96% similar.)
So the three guys from Hebrew University thought something very clever. They wondered that if the DNA,( and hence our potential brain chemistry), was the same with these sister species, jjust that maybe different DNA was turned on in each of us.
Here’s something you have to know to understand this: every cell in your body has the same DNA, its just not all ‘turned on’. If the cell happens to be in your testes, it only decodes that part of your DNA for instructions on making sperm. If it’s a seratonin receptor in your brain, the part of your DNA that turns on is the part that can make the receptor. But all the instructions for everything about you are in every cell of your body. Not only can they be turned off and on, but they can do something in the middle, they can be slightly on or slightly off.
The Hebrew U. researchers devised a way that they believe could tell them which genes were turned on if you were a Neanderthal or Denisovan, and then compared that with the ones used in Homo sapien. And guess what they found? Between the three of us, we had the same genes, but their ‘expression’ (their level of turned on-ness or off-ness) was very different.
Can you guess where the majority of differences they found were?
It was different in the parts of our DNA that given instructions in development of the brain and skull, as well as in the immune and cardiovascular systems.
They postulate that this is why we are still here and they aren’t (The neanderthals and Denisovans). Our brain chemistry made us smarter.
Oh. My. Gosh.
To say it easily, our brain chemistry was very different. (Can you imagine? If we women think male brain chemistry is less sophisticated than ours, imagine if your boyfriend was a Denisovan.)
And then there I was last night, thinking about my brain chemistry and my favorite youngest son said this to me.
“You ever heard of “Smarter Every Day, Jan.”
“Huh,” I said, distracted by my obsessive compulsiveness, not-good chemicals swathing my brain sensors, overloading them, for over a week now. Did I mention that the Hebrew researchers also postulated that Alzheimer’s disease, autism and schizophrenia are a result of our smarter brains?
“Take a look at this,” he said.
On the Youtube screen came the cutest engineer daddy from Alabama I’ve ever seen, Destin.
Apparently Destin believes that exercising your brain, learning something every day, getting a little bit smarter, is good for you. And he’s just cute as heck doing it. (A lot of people believe this, there is good solid research that using your brain is just as important for you as exercising your body.)
Amen, brother. Preach on.
I wasn’t surprised he ends each video with Psalms 111:2.
It’s truly beautiful to see the majesty of creation. It brings joy when God brings you just a little closer to the power He wields.