Have you ever compared yourself to a mouse? Some of you might say that when you felt ashamed you felt as small as a mouse. But if you thought about it, you’d probably say we have nothing in common with mice. I like cheese… but lots of creatures like to eat cheese. I don’t know, when I think about it, mice seem so INCREDIBLY different from us humans.
So then why are mice one of the most common test subjects before things are tested on humans? It seems that almost every scientific article I read that did animal testing was testing mice. Are we really that similar that a test on a mouse proves something about humans? Weirdly, the answer is yes. Genetically, mice and humans have 90% identical genomes. In some individual genes they are 99% identical. These more similar genes are often those required for function, so these genes remain the same in all mammals and have been passed down since our common ancestral relative over 80 million years ago. Some genes determine how individual cells function and are thus identical even to plants, but that is where the similarities run out for them.
This similarity to humans and their relative ease to breed is why 95% of all lab animals are mice or rats. A similar genome leads to similar genetic, biological, and behavioral characteristics between mice and humans, making it relatively easy to replicate human diseases and symptoms in these little creatures. Even though I’ve seen dozens of experiments performed with mice, studying anything from cancer to autism, I still think of mice in a maze when I think of mice being studied.
Seriously, all I can think about is that age old experiment where mice are put into a maze or forced to solve some sort of puzzle. Then at the end when they are able to solve it, they get a reward. Receiving this reward would then flood their brain with dopamine, the feel good chemical, and it would make them want to continue solving puzzles. Science is fascinated with dopamine because it seems to be a large factor in why we choose to do things. When we repeat the same action that causes dopamine, the mere anticipation of the action can flood our senses and give us that reward feeling. It certainly happens in mice. Simply solving the puzzles would cause a dopamine release, eliciting a happy response even without the reward.
Not too surprisingly, we have that same dopamine release as a mouse when we figure out a puzzle. I saw it happen firsthand on Sunday. In our youth group, my 10th grade girls and I were reading the section in Acts chapter 9 that talks about Saul’s conversion.
We read verses 1-9 and one girl’s hand shot up. She asked, “Who is Saul?” I began to explain how he was a Jew who was trying to squash the Christian rebellion from Judaism. He was doing so in very violent ways. He was pleased with the murder of St. Stephen (who we had just talked about). Another girl chimed in, “But it WAS a rebellion. The Christians were turning away from Judaism, right?” I went on to say that Saul would later see this conversion not as a turning away from Judaism, but as a continuation, a fulfillment of the Jewish prophecies and promises. Then I mentioned that he had written about it in some of his letters, reiterating how Saul/Paul had written a large portion of the New Testament.
It was at this moment that the original question asker’s eyes got SO BIG! Her mouth dropped open. She exclaimed, “WAIT! This is THAT Paul?! THE Paul?!?” I nodded and she was just freaking out. Similar to the dopamine release the rats got when they were able to solve the puzzle, I could physically see that chemical response happening in this girl’s brain. She was putting it all together and getting this great joy in her discovery.