The UU's have me teaching about Chas. Darwin
to the Sunday School classes. Last week, I had the 2d through 4th graders. We did this very clever exercise that I got out of this clever book. The book had you doing it with pennies and nickels, but I found it much more satisfying to do it with coloring pages of peacocks and with an actual picture of the predator.
I had seven kids, so I gave them each 7 coloring pages with peacocks on them and told them to set one aside and color the rest. If I'd had more time, that would have been enough of an activity for one day, but I only had one class.
I had the kid who finished first also color in a picture of a fox. I made it a fox to keep it fairly true to life. I looked it up. Foxes ARE natural predators of peacocks, albeit eggs and chicks, mostly.
Then I lined up eight uncolored pictures and said, imagine that this is a group of plain colored birds, but then (adding two colored pictures) a few birds are born to the group that have a little mutation -- they have colored feathers. So now I have eight plain birds and two colored birds lined up on the floor. Lined up on a blackboard with masking tape would probably be easier to follow.
Now, why might colored feathers be good news for a bird? Attract a mate (Some giggling from the girls.) Why might colored feathers be bad news for a bird? Easier for predator to find.
OK, so let's have our fox eat 1/4 of the plain colored birds and 1/2 of the brightly colored birds (Fox comes and grabs two of the uncolored pictures and one of the colored pictures.) But then let's have each plain male have only one baby and let's have each colored male have four babies. Bring each of the remaining six plain pictures down to the next row, bring the remaining colored picture down and add three more colored pictures. Now you have six plain and four colored.
Now, let's have our fox eat 1/4 of the plain males and 1/2 of the colored males (Fox comes and grabs 1 plain and two colored pictures.) But then let's have each plain male have only one baby and each colored male have four. Bring the five plain down to the next row. Bring the two colored pictures down to the next row and add six colored pictures.
Repeat until the point is made. Obviously, this is only a model. It's not really all THAT close to real life. But it shows a couple of really important points about evolution.
1) Individuals don't evolve. The bird himself doesn't change. The composition of the group changes.
2) The change is not necessarily progress. In our example, colored feathers are often bad news (Mo' color, mo' problems?).
3) Even if a trait is bad news for the individual, if it is good news for the group, it will still get selected for.
I love this lesson. I wish someone had taught it to me when I was little. I think most mainstream American kids are little Lamarckians who can easily be shouted down by any home-schooled kid with a pamphlet about how the earth is six thousand years old.
Next week, I have the kinders and 1st graders. I think we'll just look at fossils.
I was part of a movement of "dinosaur moms" when I lived in Maryland (Astrodon Johnstoni is the Maryland state dinosaur.) Which is nothing more than this -- dinosaur moms delight in the half-feral nature of the beasties they parent, even as they whisper Shakespeare and Kierkegaard in their ears at night.
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