The room was organic in a mildly disgusting way. I had to take a colonoscopy before they would let me go to Mars, but they did let me watch, and the walls here looked like the inside of my large intestine then, pink and slippery. That gave me a whole new attitude toward the air lock. There was no furniture in the room, no windows except for two portholes, one on each side of the air-lock lips. Not a sound.

“I will introduce you to the Other- prime, though of course it cannot respond directly.” He touched the wall, and a dark oval appeared, like wet glass. We stepped forward.

I’m afraid I made a little noise of alarm. It was, in a word, a monster. A word that shouldn’t be in a xenobiologist’s vocabulary, but there you have it.

The creature was all chitin and claws, hard shiny brown with yellow streaks and blobs. Six smaller claws, about the size of human arms, circled the thorax. A seventh one, twice as big, curled over the top like a scorpion’s tail. A powerful serrated vise.

The biologist in me immediately wondered what was in its environment that required such armor and strength. “How big is it?”

“About twice human size,” Spy said. “It won’t hurt you, though. Too warm out here for it to survive.

“It is looking at you through me and wants to say something. I will relay the message in a few minutes.”

I studied the creature while we waited. It looked more like a huge crab than any other terrestrial animal. No crabs on Earth were that big, I thought, except maybe the long spindly ones that live on the bottom of the ocean, spider crabs. This guy could eat them alive.

Which again raises the question, why? None of our speculations about its environment, living in liquid nitrogen, considered the possibility of strong, fast predators.

Of course, it couldn’t react fast, which would explain the armor.

Maybe our assumptions about body chemistry were wrong. Temperature chauvinism. The fact that this species is slow doesn’t mean that all nitrogen-based cryogenic life-forms are slow.

So that’s the next question. If the environment has swift, strong predators, what did the Others evolve from, when a snail could run circles around them? Well, just because they’re smart doesn’t mean they’re at the top of the food chain. There are plenty of environments on Earth where the crown of creation would be lunch.

It would be fascinating to investigate the Others’ planet and see whether it was biologically as complex as Earth. Mars never had been, or at least we’ve never found any fossils you could see without a magnifying glass.

Maybe the Others’ planet had a whole phylum of smaller and less complex crablike creatures, culminating in this beautiful example.

It was beautiful, in its way.