Gizmo lost a feather and I found it.
It probably says something about me that I can take a closeup photo of one of Gizmo’s lost feathers and suddenly have a phrase like “Ontogeny recapitulates phylogeny” (Ernst Haeckel) pop into my head. When I brought this image up on my computer screen I was struck by how much the barbs of a bird’s feather look like the primary lamellae of a fish’s gill. And when I looked up the structure of a feather I realized there is a reason for that observation; they are very similar, the birds feather also has secondary barbules that are similar to secondary lamellae, but serve a different purpose….
While the primary and secondary lamellae of a gill are used to direct water flow and maximize gas exchange, the barbs and barbules of a feather are designed to direct air flow and maximize lift.
Mother Nature is amazing, she doesn’t do things in isolation, and she doesn’t waste a good design on only one creature.
Biology is cool 🙂