One of my anthropology professors said that during one of his lessons about evolution a student commented "I didn't come from no monkey." He said his response was "You are right. You did not. But you do have a common ancestor."
I also had a similar encounter with another student who said they were "not sure if they believed in evolution because they don't believe we came from monkeys."
Evolution can be very confusing and a lot of people (including myself for quite some time) think of evolution as being linear. This species gave rise to only that species and so forth. That is what the evolution bumper stickers make it look like. They also make it look like we came from chimpanzees, which is even more confusing considering chimpanzees are still around. So why, then are chimpanzees still around? What even is a common ancestor?
It is a common known fact that we share 98% of our DNA with chimpanzees. We are certainly related to them, but not in the way we tend to think of. We actually have a common ancestor with chimpanzees that is known as Sahelanthropus tchadensis. This species was discovered in Chad and lived around 6-7 million years ago and gave rise to other species in our evolutionary history, including chimpanzees and humans. It was not a linear history that brought us to where we are today. One species gives rise to another and they can split, like branches.
It is also weird to think that we are so different from chimpanzees even though we share so much DNA. It made me curious as to how genetically we can be so similar and yet be so different. In one article it discusses how the same genes can be turned on and off to ultimately provide different functions. "...even two identical stretches of DNA can work differently --they can be 'turned on' in different amounts, in different places or at different times" (DNA: Comparing Humans and Chimps, n.d.). A major example of this is the genes in the brain. Thousands of differences can greatly affect brain development and function.
Hominid Evolution
Skull of Sahelanthropus tchadensis
Chimpanzee Skull
Human Skull
https://www.amnh.org/exhibitions/permanent/human-origins/understanding-our-past/dna-comparing-humans-and-chimps
https://www.abc.net.au/science/articles/2011/10/04/3331957.htm
Interesting post here. I like how you start it with an example of how the question comes up in real life and then give an answer that is rooted in paleoanthropology. I think you are right that the problem is that people think in linear terms. We might need to come up with better ways to explain evolution so that people don't mistake what is being said. And very nice use of images here. I like how you used examples from the class here!
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