Ever wonder how some of those Sci -Fi authors come up with such interesting and strange aliens? Me too. I think I am better off staying closer to home. Good thing there are plenty of strange things right here on Earth. But that’s not good enough for your own original creature, right? So start with creatures that already exist, then find out something really weird about them and go with it!
For example, whales were once land animals. Honest! Check out Wikipedia here at Evolution of cetaceans. So perhaps try to imagine what the in-between stages might have been like, or what would happen if they went back to land.
Or chicken with teeth. What would it be like it chickens started having teeth again? Farms would be pretty different.
What about winged cats? This link is to the most comprehensive article I have ever seen on the subject (kudos to you Sarah Hartwell). If you are too lazy to go read it, no they are not really wings, yes, once upon a time some people thought they might be. So now use your imagination again! Flying cats! Chasing flying mice perhaps? If they really had been wings, why? What would be the evolutionary purpose of them? What if they were just now starting to develop, and in the next twenty years, all cats had them?
Or the Bloop! This one is kind of old news and there was never much information on it anyway, so actual information is hard to come by, and fiction can be prevalent. That being said, in 1997 military microphones detected the ‘Bloop’, a sound some say may be organic in origin. If so, what kind of creature could possibly have made this noise?
There are so many strange things that people have actually encountered, it shouldn’t be too hard to tweak one of them just enough for a great Sci-Fi story!