“Not really open. The mat flows down, see, and covers this pool. Keeps it from drying out. Saving its resources maybe?”
She scooped out some of the filmy pool water and put it under her hand microscope.
Marc said, “It’s just algae, right?”
She did not answer. In the view were small creatures, plain as day.
“My God. There’s something swimming around in here. Marc, look at this and tell me I’m not crazy.”
He looked through the scope and blinked. “Martian shrimp?”
She sighed. “Trust you to think of something edible. In a pond this small on Earth there might be fairy shrimp, but these are pretty small. And I don’t even know if these are animals.”
She hurried to get some digitals of the stuff. She scooped some up in a sample vial and tucked it into her pack. Her mind was whirling in elation. She studied the tiny swimming things with breathless awe.
So fine and strange—and why the hell did she have to peer at them through a smudged helmet?
They had knobby structures at one end: heads? Maybe, and each with a smaller, light-colored speck. What?
Could Mars life have taken the leap to animals, bridging a huge evolutionary chasm? On the other hand, these could be just mobile algal colonies, like Volvox and other pond life on Earth. Whatever they were, she knew they were way beyond microbes. She bent down over the pool again, shone her handbeam at an angle.
The swarm of creatures was much thicker at the edges of the Mars-mat—feeding? Or something else?
She couldn’t quite dredge the murky idea from her subconscious. The arrangement with the mat was odd, handy for the “shrimp.” What was the relationship there? Some kind of symbiosis? And how did the swimming forms get to the pool?
She and Marc climbed down from the ledge, playing out cable. As they descended the mist thickened and the walls got slick and they had to take more care. The cable was getting harder to manage, too. She could not stop her mind from spinning with ideas.
On Earth, hydrothermal vent organisms photosynthesized kilometers deep in the ocean, using the dim reddish glow from hot magma. The glow became their energy source. Could some Martian organisms use the mat glow? Wait a minute—
“Marc, did you notice anything peculiar about the shrimp?”
He paused before answering. “Well, I don’t know what they should look like. They looked sorta like the shrimp I feed my fish at home.”
“Did you notice their eyes?”
“Uh…”
“The knobby ends, those had lighter specks, remember?”
“Yeah, what about them?”
“So you saw them too.”
“Why, what’s the matter—Oh.”
“Right!”
“I see, they shouldn’t have eyes.”
“Good for you. I’ll make a biologist out of you yet. On Earth, cave-dwelling organisms have lost their eyes. Natural selection forces an organism to justify the cost of producing a complicated structure. You lose ’em if you don’t use ’em.”
“So if they have eyes—”
“On Earth, we’d say they were recent arrivals from a lighted place, hadn’t had time to become blind.”
“But that’s impossible. The lighted parts of Mars have been cold and dry for billions of years. Where would they have come from?”
“I agree. So my next choice is that it’s not dark enough here to lose the eyes.”
“That glow is pretty dim.”
“To us, maybe. We’re creatures from a light-saturated world. Our eyes aren’t used to these skimpy intensities. Closest parallel on Earth to these light levels are the hydrothermal vents. There are light-sensitive animals down there, even microbes able to photosynthesize.”
“Maybe they’re not even eyes.”
“They’re light-sensitive. The critters clustered under the beam from my scope.”
“Wow.”
“I need more information, but at the very least it suggests that the glow is permanent. Or at least frequent enough to give some advantage to being able to see. And that means there should be something that can use the glow as an energy source. Maybe the mat is symbiotic—a cooperation between glowing organisms and photosynthesizers?”
“Yeah… That suggests the glow is primary. What’s it for?”
“Don’t know, just guessing here.”
“Curiouser and curiouser, as Alice said.”
“1 didn’t know boys read Alice in Wonderland.”
