"I don't think he will."
"Because he's your son..."
The door banged shut. Outside, they heard their daughter screaming and shrieking, "What is that?"
They heard Jamie say, "He's a chimp, and we're climbing trees."
"Where'd you get him, Jamie?"
"He's Dad's."
"Does he bite?"
They couldn't make out Jamie's answer, but through the window they saw the tree branches swaying and moving. Giggles and laughter from outside.
"What are you going to do with him?" Lynn said.
"I don't know," Henry said.
"Well, he can't stay here."
"I know that."
"I won't have a dog in the house. I certainly won't have an ape."
"I know."
"And besides there's no room for him."
"I know."
"This is really a mess," she said.
He said nothing, just nodded.
"How the hell did this happen, Henry?" she said.
"It's a long story," he said.
"I'm listening."
When thehuman genome was decoded, he explained, scientists discovered that the genome of a chimpanzee was nearly identical to that of a man. "All that separates our two species," he said, "is five hundred genes."
Of course, that number was deceptive, because human beings and sea urchins also shared a lot of genes. In fact, nearly every creature on the planet shared tens of thousands of the same genes. There was a great underlying unity of all life, genetically speaking.
So that created a lot of interest in what had caused the differences in different species. Five hundred genes weren't a lot, yet a great chasm seemed to separate chimps from human beings.
"Many species can crossbreed to produce hybrids - lions and tigers, leopards and jaguars, dolphins and whales, buffalo and cattle, zebras and horses, camels and llamas. Grizzlies and polar bears sometimes mate in the wild, producing grolars. So there was a question of whether chimps and humans could hybridize to make a humanzee. The answer seems to be no."
"Somebody has tried?"
"Many times. Starting back to the 1920s."
But even if hybridization were impossible, Henry explained, one might still insert human genes directly into a chimp embryo to create a transgenic animal. Four years back, when Henry was on sabbatical at the National Institutes of Health, he was studying autism, and he wanted to know which genes might account for the difference in communication abilities between people and apes. "Because chimps can communicate," he said. "They have a range of cries and hand gestures; they can organize themselves into very effective hunting parties to kill small animals. So they have communication, but no language. Like severe autistics. That's what interested me."
"And what did you do?" his wife asked.
In the laboratory, under a microscope, he inserted human genes into a chimpanzee embryo. His own genes.
"Including the genes for speech?" she asked.
"Actually, all of them."
"You inserted all your genes."
"Look, I never expected the experiment to go to term," he said. "I was looking to retrieve a fetus."
"A fetus, not an animal?"
If the transgenic fetus survived eight or nine weeks before it spontaneously aborted, there would be enough differentiation that he could dissect the fetus and advance his understanding of speech in apes.
"You expected the fetus to die?"
"Yes. I was just hoping that it would carry long enough - "
"And then you were going to cut the fetus up?"
"Dissect it, yes."
"Your own genes, your own fetus - you did this in order to have something to dissect?" She was looking at him like he was a monster.
"Lynn, it was an experiment. We do this kind of thing all the - " He broke off. No point going there. "Look," he said, "the genes were close at hand. I didn't have to get anybody's permission to use them. It was an experiment. It wasn't about me."
"It is now," she said.
The questionHenry was trying to answer was fundamental. Chimps and humans had split from a common ancestor six million years ago. And scientists had long ago noticed that chimpanzees most closely resemble human beings at their fetal stage. This suggested that human beings differed from chimps in part because of difference in intrauterine development. Human development could be thought of as having been arrested at the chimp fetal stage. Some scientists felt it was related to the eventual growth of the human brain, which doubled in the first year after birth. But Henry's interest was in speech, and for speech to occur, the vocal cords had to move down the throat from the mouth, creating a voice box. That happened in humans, but not in chimps. The entire developmental sequence was immensely complicated.
Henry hoped to harvest a transgenic fetus, and from that to gain some knowledge of what drove the change in human development that made speech possible. At least, that was his original experimental plan.
"Why didn't you remove the fetus as you intended?" she asked him.
Because that summer, several chimps contracted viral encephalitis, and the healthy chimps had to be moved away for quarantine. They were taken to different labs around the East Coast. "I never heard anything about the embryo I implanted. I just assumed that the female had spontaneously aborted in a quarantine facility somewhere, and the fetal material was discarded. I couldn't inquire too closely..."
"Because what you did was illegal."
"Well. That's a strong word. I assumed the experiment had failed, and it was over."