Answer:
The change is greatest for the solid ball
So the dark butterfly camouflages better on the tree. Where as the white one can clearly be seen and identified. A predator will also easily spot it and kill it. The dark butterfly has evolved over time to the color that it is, to best help it survive. This is also shown in the tread on the graph.
Hope this helps!!
I believe it is scientific laws.
Due to the cones in your eyes(OR else they're called the photo receptors together with Rods)
