“Fragile? It’s tough—probably older than ours. The DNA shows that the Marsmat has a lot of similarities to our most ancient bacteria, right? It endured the loss of the planet’s atmosphere, the freezing-down, and heavy bombardments—then grew underground.”

“We cannot know what reawakening this water will do to the Mat. The Precautionary Principle plainly provides that insight.”

She always hated hearing the capitals on big, inflated ideas. “We should never do anything for the first time, I get it.”

“I don’t think that’s a fair—”

“Let me guess, next comes ‘rocks have rights,’ yes?”

He gave her a long, stern glare. “You won’t hear me out.”

“The Mat isn’t afraid of water—it welcomes fluids, and uses them in its own weird way.”

“You support Marsforming, then.”

“Look, life is a one-way trip.” She spread her arms wide. “We’re all permanently exiled from our past. Mars colonists—all colonists—are no different. In addition to leaving behind the time of their pasts, they also leave behind the place, Earth. But in return they get to create a world where none existed before, a whole new planet.”

“But not for the Marsmat that lives here.”

“It’s an anaerobe. When we have an oxygen atmosphere here, it will still be safe far underground, just like the anaerobes on Earth.”

He shook his head. “We are not so superior that we should manage another life-form. Especially a sentient one.”

She stood her ground. “Why not manage wildlife? Back Earthside, we slip contraceptives into the food of overpopulations of deer. In California, people teach condors not to perch on power lines, so they won’t get electrocuted. People teach whooping cranes how to migrate, and pick up salamanders to get them across roads—you name it, we do it.”

He crossed his arms, the classic hostile stance. “We’re radically altering its world.”

“If the Marsmat wants to come up, to colonize the surface—as it did before—it will make up its own mind.” She paused, her caution saying, Don’t get into politics talk! So she finished lamely, “Or whatever it uses for a mind.”

“Such species-specific ethics are unacceptable.” He waved an arm at the plain below. “This is a separate world, with separate rights of its own.”

She couldn’t resist. “Not once we’re here. We’re life!—connecting at last to other life, the Mat. Our ethics needs to benefit humanity. I won’t debate whether the Marsmat’s interests can be considered as equal to human interests. It’s a microbial intelligence. It’s not like us, and moral arguments like yours—well, you contradict yourself every day!”

He looked puzzled. “What? How?”

“Look, if bacterial interests trump human interests, then mouthwash should be banned, right? We shouldn’t chlorinate our water supplies. Hell, antibiotics should be illegal. If bacterial interests are superior to human interests, then Albert Schweitzer and Louis Pasteur should be denounced for crimes against bacteria!”

Her mother had once said, “Speak when you’re full of fire and you will make the best speech you will ever regret.” Rachel wondered where her vehemence was coming from, and then went on, throwing caution to the wind. “Now, it’s vital to save the Amazon rain forest, because a world without that would be a poorer one. Plus, no inheritance for our descendants. But Mars?”