The subject of biomineralization also allows comparing the explanatory power of design over Darwinian evolution.
The Fibonacci spirals in plants have long attracted scientists and puzzled them as well. How do they form?
The way an embryo develops shows a method of patterning that makes use of physical processes as if they conform to a predetermined plan.
How much do you have to know to make a design inference?
Even down to the level of molecules and genes, there doesn’t seem to be any physical reason for plants to grow “Golden Ratio” patterns.