I have been very fortunate to have had some of the schooling I’ve had. Neither of my parents had much chemistry or biology at all in school. I do not blame people for not knowing. I do blame people for deliberately ignoring.
It is mind boggling to me how many people know for a _fact_ that OJ Simpson was guilty because of some DNA evidence and at the same time _deliberately_ ignore the DNA evidence of evolution.
There are also those who for some reason believe that “both sides should be taught” in public schools. I would guess that these people think that they are being fair. But they are _not_ being fair _to the kids_.
We have phylogenetic trees now based on step by step by step single base pair changes in DNA. A _Mount Everest_ of data compared to a tiny single grain of sand that was the evidence against OJ.
How many people out there would say that we should teach (aka repeatedly drum into) some kids that they will fall off the edge of the Earth if they explore too far from home while at the same time teaching other kids that exploration is a wonderful and marvelous eye opening experience? How many? Not any that I want to associate with.
Teaching something that inhibits further exploration and learning is not what I want to be around.
Let’s teach that the Sun revolves around the earth because God made the earth first and then the sun in the sky. That’s “the other side” of what we know scientifically and “we should teach both sides.”
The DNA evidence against OJ, which a huge number of people believe, was DNA fingerprinting. DNA fingerprinting is a much more crude method of DNA analysis than sequencing. We now have exact sequences of sections of DNA for hundreds of thousands of organisms. We can now group species phylogenetically not because of what they or their bones _look_ like but because of what the sequence of their DNA itself reveals.
Bright, creative thinking people more than 100 years ago started thinking that our mitochondria, the fundamental power plants in each of our cells, had properties that indicated that they might once have been bacterial parasites. One of the properties that made people wonder was that each mitochondria contained its own DNA. In fact chloroplasts do as well :-)
Today we can sequence mitochondrial DNA and compare this sequence to DNA from other organisms. The exact linear order of hundreds of thousands of base pairs from the DNA of human mitochondria very, very, _very_ closely matches that of bacteria from the purple nonsulfur group. Look at the picture –in the blue “bacteria” blob — off to the right amongst the proteobacteria . That is _our human_ mitochondria. This entire post contains about 705 total words if you found an identical copy of this series of paragraphs somewhere else except for less than 5 single word differences you would not assume that someone else wrote it independently!
Now that I’ve got you looking at the picture, look up at the green blob. Now to the left and down — and the labels from the bottom up are “fungi”, “nucleariids”, and “animals”. The actual length of the lines between forks is a reasonably good (probably the best measurement we’ve got) of how similar biologically the organisms are. Humans, chimpanzees, elephants, dinosaurs!! (Yes all the dinosaurs the feathered dinosaurs ☺, reptiles, Koi, frogs, insects, worms –are _all_ represented on that one tiny line labeled “animals”.
Your brain is probably hurting at this point. I know I’m asking a lot, but I ask you: how is it that people can understand that antibiotics developed for us (up on the animal line) that target and kill organisms as different from us as the organism that causes staph infections
(Staphylococcus aureus — a member of the Firmicutes), way, way, _way_ down in the blue blob at the bottom; that those antibiotics, can have bad side effects on us, and yet the insecticides that kill insects who’s cellular systems are so similar to us that they are only a tiny, tiny fraction of a line away from us, can have absolutely no side effects on us humans at all??? And most insecticides are neurotoxins.
They target the cells in insects that are evolutionarily the sisters and brothers to _our_ brain cells.
Bob
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