The Banana Problem

The worksheet said: Humans share about 50 percent of their DNA with a banana. Underneath it said: Discuss.

"That's wrong," said Maya. She had a banana in her hand, the spotty kind her grandmother saved for bread. "It has to be wrong."

"Why," said Soren. Not arguing. He wanted the reason.

"Because look at it." Maya held the banana up next to her own face. "It's a banana. I'm a person. We are not half the same. I'm not half banana."

"The sheet didn't say half banana. It said half the genes."

"Same thing."

"It's really not," said Soren, and opened his notebook, and wrote the number 50 with a question mark after it.

Maya put the banana down. "Okay. Test it. What does a banana even do."

"It's a fruit. It grows. It rots." Soren looked at the bowl. One of them had gone soft and brown at the bottom. "It's rotting right now."

"What do I do."

"You grow. You rot eventually, I guess. Don't write that down, I'll write it." He wrote it down.

"That's nothing," said Maya. "Growing and rotting. Everything does that. A mushroom does that. The bread does that if Gran forgets it."

They both stopped.

"Everything does that," said Soren again, slower.

Maya picked the banana back up. She was quiet, and then she said, "What's the smallest thing a banana has to do to stay alive. Like the smallest job."

"It's made of cells."

"So am I."

"Each cell has to make energy. Or it dies. The banana cell, my cell, all of them."

"How does a cell make energy."

Soren chewed his pen. "There's a machine inside it. Lots of tiny machines. They take sugar and break it and that's the energy. We did it in a diagram, the little oval ones."

"Mitochondria," said Maya, getting it out fast before she lost it. "The oval ones. Gran has them. I have them. Does the banana have them."

"It has to. It's alive. It runs on sugar." Soren looked at the banana like it had said something to him. "A banana is basically a bag of sugar."

Maya turned the banana over in her hands. "So the machine that breaks the sugar. In the banana. And the machine that breaks the sugar in me. Are they the same machine."

"They can't be exactly the same."

"Why not."

Soren started to answer and stopped, because he didn't have a why not. He had a why yes, and it was sitting in his chest getting bigger.

"A machine is made of parts," he said carefully. "The parts are proteins. The instructions for the parts are the genes. If two things make the exact same machine, they need the exact same instructions."

"The exact same genes," said Maya.

"The exact same genes."

They looked at each other across the worksheet.

"So the banana," Maya said, "has my instructions. For the sugar machine."

"Or you have the banana's."

"Whose came first."

Soren put his pen down. This was the part. He could feel it the way you feel a step in the dark that isn't where you thought it was. "Neither. That's the thing. There was something before both. Something tiny, a long time ago, before bananas and before people, before anything you could point at. And it figured out the sugar machine. And it worked so well that nothing ever changed it."

"Nothing ever changed it," Maya repeated.

"For billions of years. Everything after just kept it. The banana kept it. You kept it. The mushroom, the bread mold, Gran, the tree outside, all of it got handed the same instructions and nobody dared rewrite them because if you rewrite them you die."

Maya sat down. She was still holding the banana.

"So the fifty percent," she said. "It's not the banana parts. It's not the yellow and the curve and the seeds."

"No. Those are the new genes. The few. The half that's different is the half that makes a banana a banana."

"And the half that's the same."

"Is the half that makes anything alive at all," said Soren. "The oldest half. The boring half. The half nobody ever talks about because it just runs underneath everything, quietly, in you and in this." He pointed at the fruit in her hands.

Maya looked at the banana a long time.

"I feel weird," she said.

"Good weird or bad weird."

"I don't know yet." She set the banana upright on the table so it stood like a small person. "It's like. I always thought the important part of me was the part that's only me. The face part. The Maya part."

"And it turns out half of you is the part that's the same as everything," said Soren. "The part you have because you're alive. Not because you're you."

"And that part is older than people. Older than animals. Older than this whole kitchen put together."

Gran came in then, wiping her hands, and saw the two of them sitting with a banana standing up on the table between them like a guest.

"Are you making the bread or worshipping it," she said.

"Gran," said Maya, "you have the same sugar machine as this banana."

"I certainly do not," said Gran, and took the soft one from the bowl, and broke it in half to mash it.

Maya watched the inside of the banana come apart, the soft pale stuff that was nothing but sugar and water and a billion years of instructions kept exactly as they were.

"She does, though," Maya said, very quietly, only to Soren.

Soren wrote one more line. Then he reached across, picked up the standing banana before Gran could mash it too, and held it up to the window light, turning it slowly, looking for the part of it that was also him.