Over in Backfile, you will find an eleven part document called How to Build a Culture, inspired by Poul Anderson’s How to Build a Planet.
I could also write a paper called How to Build an Ecosystem, but who needs to read all that. A couple of posts here should cover the subject, without boredom or overload.
The fact is, simply peppering your planet with a few well chosen and deeply odd critters is enough in most cases. Andre Norton did it all the time, and it worked for her. The frawns and yoris on Arzor are simply transmogrified bighorn sheep and alligators, but so what? They provide plot points and local color, and that is all that is asked of them. Marion Zimmer Bradley gave us a mammalian snake, a hyper-weasel, and an intelligent dinosaur who sent out pheromone soaked calling cards in Hunters of the Red Moon. What more could you want? In Jandrax, showing up now in Serial, my native animals were distinctive, but most were mammalian, as one would expect from ice age migrators.
When I wrote Cyan, I faced a different situation. My crew was set down on an alien planet for one year, with the task of coming to understand its weather, geology, and ecology in order to prepare for colonization. They were all scientists, so their actions and conversations called for a deeper understanding of their new world than any other kind of science fiction novel would have required. Actually, that challenge was half the fun.
When I began Cyan, I had been studying ecology for about twenty years, starting back when I had to explain what the word meant. I later came to understand the essence of Earth’s taxonomy in the most rigorous possible way – I had had to condense it to a level which middle school students could understand without dying of boredom.
Drop a salmon egg on the gunwale of your canoe and it will dry out in minutes. A chicken or turtle egg would survive the same treatment. This is the meaning of amniote egg (although there are other, competing meanings). Creatures who lack them, must lay their eggs in water. The rest of the chart should be clear, although simplified. For example, birds have scales on their legs as well as feathers elsewhere, and I skipped Dinosauria altogether.
Now pull up a chair and lets build Cyanian ecology. It needs to be wierd but recognizable – that’s the key to all science fiction invention. We also need restraint. You can only explain so much to your reader without losing them, and beyond a certain point, your backstory is wasted effort.
Come back tomorrow and we’ll dive more deeply into Cyanian ecology.