I'm pretty sure somebody is handpicking the featured creatures because there's a separate listing for the most popular, highest rated ones.
I remember a couple days in a row when the entire first row of featured creatures was all creatures that look like something, and I wish that whichever person at Maxis is in charge of picking those out would give it a rest. Sure, it can be clever, and if you want to feature the best ones, fine. But let's also feature some creatures that are, you know, creatures.