Mind the Gap

When I’m thinking about the evolution of animal forms, as one does, mostly I’m considering animals that exist, or that previously existed, and wondering what conditions and adaptations led to their rise and persistence. Which beak shape gave that bird an advantage where seeds were like stones? Which wing length made sense for a bird that needed to soar, not hop? What combination of traits meant fitness, and thus survival? And why the goofy feet, regardless?

But here’s a different question...