As acknowledged previously, there are plenty of folks who choose not to support evolution. Quite frankly, I think people’s views on such matters are no body’s business and ultimately pretty inconsequential- that includes people on both sides of the issue. Live and let live, people. That being said, there is one phrase I have heard over and over from evolution opponents that I just can’t move past. It is usually said with a tinge of condescending sarcasm that rubs me the wrong way. I have to remind myself that it is probably not meant to be so (who knows, maybe it is), but rather born from a lack of understanding.
“So, you think we came from monkeys?” Yup, that’s the one.
First off, if you mean “so, you think that we share a common ancestor with present-day monkeys?” then yes, I do believe that. I’ve come to suspect that many are under the impression that evolution is a linear process and that chimps and gorillas are the primitive forms of humans. Evolution is anything but linear, and we certainly did not evolve from chimps. Rather, chimps and humans evolved from the same animal- one that is neither human nor chimp nor gorilla. This animal is what we refer to as the “most recent common ancestor.”
I think the tone of this question is also a little grating. As if it were a nasty or offensive suggestion that we are related to monkeys. I’ve got news: if we’re going to define “monkeys” as a group of animals that includes gorillas, chimps, orangutans, etc., then that makes us monkeys. Is that such a bad thing? Primates show some of the most advanced cognitive abilities in the entire natural world (not to mention our nifty opposable thumbs). Don’t tell me you don’t get a little teary when you see KoKo caring for that kitten, or using the signs for “finger” and “bracelet” to describe a ring. Is it so bad to be a primate?
I watched a program on Discovery one time that explored what it is that makes us different from the other Great Apes. It showed this experiment that a lady conducted on human children and young chimpanzees. She has a simple box that has some doodads on top that play absolutely no functional part in the box. She allows the test subject to watch her put a food reward (candy) into the box and close it. She then demonstrates a series of arbitrary motions that include tapping the side of the box with her finger, sliding one of the doodads to the left, and flipping another doodad. She then opens the box, takes out the food reward, and consumes it. She reloads the box with candy and places it in front of the test subject.
Since none of her tapping or sliding or flipping made any difference in her to ability to open the box and retrieve the food reward, it would seem silly and almost stupid to blindly repeat her motions, right? Why not just open the box and eat your candy?
Chimps did. No problem. Just opened it right up and took out the Jolly Rancher.
Human kids unfailingly repeated her arbitrary motions, then opened the box and ate their reward. Iiiiinteresting, huh? Here in lies one of our greatest adaptations that has allowed for the success of humans. We learn from our elders and from a very young age repeat their actions as a means of passing down generations’ worth of learned skills. Why do you brush your teeth? Well, your parents taught you to do it when you were little and so you just did it. Now that you’re older, you know it’s to keep them from rotting your face off. But in your critical learning years, you repeated what you were shown. We as individuals do not have to start from square one when it comes to learning things like building a house, or opening a candy box, because our highly developed brains and extensive parental care allow for us to take advantage of our forbearers’ know-how. We are standing on the shoulders of hundreds of thousands of years worth of trial and error.
So while we are pretty amazing as a species, we as individuals don’t just open the box and take the frickin Jolly Rancher. No, we did not “come from monkeys.” But even if we did, what’s so horrible about that?
I blame those stupid drawings that you see on bumper stickers and other stickers that show the linear progression of a "monkey" slowly becoming a cave man.
ReplyDeleteOh also, we share a 99% gene identity with the chimpanzee. Meaning, our genomes are 99% similar. Does that mean the 1% difference in our genome is what makes us human? Actually, the real difference is in the regulation of the gene expression. If you look at a gene expression profile of a human vs a chimp, you'll see that it's wholly different. We possess nearly the same genes but it's just regulated differently. Just goes to show that DNA alone doesn't have the answer to everything, there are much more complex mechanisms in place that can control phenotype.
ReplyDeleteCool! I was going to put the little 99% similarity factoid in, but then I stopped myself because I wondered this very thing. Do you know how they develop a "gene expression profile?"
ReplyDeleteHmm it depends. The easiest way I can think of is to use a microarray. I've never done a microarray before but this is the basic logic behind a microarry. Basically, a microarray is a giant plate with tons and tons of little wells, each well has a gene probe for a particular gene. So then you extract the mRNA (very tedious process that I do all the time) and inject a fluorescent dye that binds to the mRNA. Here's the cool part, you then pipette the tagged mRNA into the wells with the DNA probes. Because DNA and RNA will indeed hybridize and bind to it's complement sequences you'll have the tagged mRNA bound only to the sequences that are being expressed! Then you just read which wells are glowing due to the tag you put on the mRNA and boom you have a gene expression profile.
DeleteIn my lab, I'm measuring gene expression as well, but only for 3 genes that are hypothesized to be related to toxin production of our fungus. I extract the mRNA, use reverse transcriptase to transcribe it into DNA, then add DNA primers that I ordered for my genes of interest and put it in a PCR machine. Then run it on a DNA gel and I check for tight bands indicating that there was DNA synthesis, which means there was indeed gene expression of my genes of interest. That whole process takes me a few days and sometimes I fail bc RNA is extremely unstable and degrades very easily.
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