The Girl wanted to play a game, and I suggested “Name the animal.”
I’m thinking of a vertebrate with no bones, I said.
“Vertebrate?” She asked.
An animal with a skeleton, I said. But in this case, no bones.
“A blobfish?” she asked. We love looking over various animal pictures, and she is especially fascinated by the Deep. I describe it to her like another planet filled with aliens, a mysterious world beneath this one – which it is.
No, believe it or not, they actually have bones, I said.
“OOH! A …. A shark!” she said.
Absolutely right, I said. Do you know why I can say it has a skeleton but no bones?
“Because its skeleton is made of … that stuff in your nose …”
Very good, I said – cartilage.
“Does it help them swim better?” She asked.
I believe they developed skeletons before bones appeared in the Creation, I said. No fish had developed bones yet, but they had developed cartilage. Sharks are one of the only animals left to have a cartilage skeleton, but it hasn’t slowed them down – they’ve been one of the main predators since the Third Age of the world.
I divided up the world for her into the main stage between extinction events, with the First Age being of Germs, the Second Age when germs combined to form bodies, and so on. It results in seven ages of life on Earth, which I describe to her like the days in Genesis – “and as the Second Age dawned the command came forth: Organise.”
“Is that right before the first fish came out onto land?” she asked.
That’s right, I said – and it might not be a coincidence. They might have found that crawling out into the air protected them from sharks that chased them.
“Thank you, sharks!” The Girl said to no one in particular. “You're naughty, but we wouldn’t be here if it weren’t for you.”