I didn’t do school last week, because I was sick; and I was at a conference on Thursday and Friday (pictures coming later, I hope) so I wasn’t able to do it then either… so getting geared up today was a bit of a challenge. It did feel surprisingly normal to just be studying, though.
Okay: part two of my story! Not quite every day so far, but getting close. 🙂 The computer won’t keep my font this time for some reason. *sigh* Oh well! It works.
Later that night after dinner, I pounced on Uncle Zade and asked him to show me. I helped him rummage up three-by-five cards and a pen, then obediently went into the living-room while he worked. When he called me back in, he had laid the cards out in five rows of four. He had drawn symbols on all the cards: the first row went circle, triangle, heart, star; the second went smiley-face, circle, triangle, heart; the third smiley-face, circle, heart, star; the fourth smiley-face, circle, triangle, star; the fifth smiley-face, triangle, heart, star. Off to the side was a circle, a triangle, a star, a heart, and a smiley-face. I looked at the set-up skeptically.
“Okay,” Uncle Zade began. I want you to put those five that are not in rows into theses rows in such a way that all the rows look the same.” I looked them over, and found that each row was missing one symbol. I managed to sort them all out into five rows of smiley-face, circle, triangle, heart, star.
“Well done!” he said, looking over my shoulder. “So this is how we use index fossils. No rock formation has all the fossils, but if we have all the rock formations to help us, we can piece this together.
“But those examples of fossils I was using earlier today—do you remember that?”
“The plants and dinosaurs?”
“Yes, those. That order is actually from a geological column, that I believe is accurate.”
“What’s a geological column?”
“A theoretical picture in which layers of rock from around the world are meshed together into a single, unbroken record of earth’s past.”
“That sounded like a definition,” I accused.
“’meshed’?” I said, confused. “Not a very official-sounding word.”
“Maybe not, but stay focused, Carol!”
“A geological column is when we lay out eras, and the fossils that are found in each era. There are thirteen eras: Precambrian, Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Jurassic, Cretaceous, Tertiary, and Quaternary.”
“That’s a lot,” I commented, wondering how in the world he had managed to memorize all that.
“Not many, actually, when you’re talking about summing up millions of years.”
“Oh, maybe not.”
“So, the Precambrian era includes fossils that are more than five hundred fifty million years old. The fossils we find in that era are of algae and bacteria—small, simple life forms. The Cambrian era is fossils that are four hundred ninety million to five hundred fifty million years old. From that era we find trilobites and similar animals.”
“What in the world is a tri… trio…”
“Yeah, that. No definitions please—you’re own words make more sense.”
“Okay, okay: trilobites were small sea creatures that lived mostly on the bottom of the ocean. They had hard exoskeletons, like lobsters. They plowed through the mud looking for food, and fossils have been found of their tracks even when actual fossils of them were not found. They are now extinct—to the best of our knowledge.
“Anyway, next is the Ordovician era, which is fossils four hundred forty-five to four hundred ninety million years old. From that era we find more trilobites, and other ocean life without bones. After that comes the Silurian era, which is four hundred fifteen to four hundred forty-five million years. In that we find no trilobites, but the other ocean life without bones. About this time trilobites probably went extinct. After that is the Devonian era, three hundred sixty to four hundred fifteen million years. That’s where we first find fish. Then comes Mississippian and Pennsylvanian, which went from three hundred sixty to to three hundred million years combined. In them we find plants.”
“Wait, Missis… sippian?” I faltered. “Pen… I mean, like the states?”
“Yes, exactly like the states. After that comes Permian, Triassic, Jurassic, and Cretaceous, in which we find dinosaurs. All together they go from three hundred million to sixty-five million years.”
My Mom happened to walk through the kitchen at that unfortunate moment, just in time to hear million years. She glanced at us, looking concerned. I squirmed and avoided eye-contact.
“Then Tertiary, from sixty-five to two point six, in which we find mammals,” Uncle Zade continued, oblivious. “And then Quaternary, from the present to two point six, in which we find people and mammals.”
“Ah…” I said. I glanced at the kitchen door. Being sure Mom had gone upstairs, I asked in a low voice, “Do my parents believe that?”
“Just what your parents believe these days is quite beyond me, Carol,” he answered with a shrug. “But I don’t think so. I think they’re Creationists, and believe that all creatures in the world came about at the same time and lived together. Some people even believe that humans shared the world with dinosaurs. We geologists would call them Catastrophists.”
“Ca-tas-tro-phist. It means that they believe the geological features of the world were formed by catastrophes, in a short period of time. We’re Uniformitarians, which means you believe that they were formed over millions or billions of years by long slow processes.”
‘We’? Did he mean him and me? I was glad my parents weren’t in the room. It bothered me a little when he talked like this. I used to be really close to my parents—before this whole church-thing.
“I’m also a evolutionist,” he went on. “Which means I believe in the Theory of Evolution.”
I yawned—because it was getting late, not because I was bored. “What’s that?”
“A theory stating that all life on this earth has one (or a few) common ancestor or ancestors that existed a long time ago. (The s on ancestor is in parenthesis.)”
I pulled my legs up onto my chair and rested my chin on my knees. “That sounded like a definition.”
“Fine. It was. In my own words, it’s…” he mused for a moment. “Let me go back to the geological column. It starts with algae and bacteria. Simple life forms. I believe that all life on earth started like that. Then animals that were a little more complex formed, then a little more, and so on, until humans were formed.”
Just then my parents walked into the room.
“It’s about time for you to be in bed, Carol,” my Dad said apologetically.
“Okay,” I said standing up. “Thanks,” I said to Uncle Zade, under my breath, hoping my parents wouldn’t suspect anything. “Good night!” I said to them, and went upstairs, drooping with sleepiness but with my mind working hard.
I lay in the dark and thought about what he had said. ‘We’? Did he really mean him and me? What was I anyway? A Creationist or an Evolutionist? I had never doubted evolution until my parents started going to church. I was never really on board with the church-thing but it had shaken me a little, I realized now. My parents believed in a God who created everything at the same time. Uncle Zade was an Evolutionist, who believed creatures had evolved over millions of years. But what was I?
Another long, long, scientific conversation. Those make for long parts. They kind-of bother me, but I can never figure out how else to get the information in!
See you tomorrow!