So today I was filling up my car at the gas station and it occurred to me that the way that gas is transferred from the pump to the car is similar to the manner in which semen is transferred from the male to the female; i.e. by inserting a funnel into a reciprocal.
This got me thinking. Is it some big coincidence that the engineers devised the same system of fluid transfer as nature? Of course not. The penis/vagina arrangement was neither intelligently designed, nor did it occur randomly. Instead, it simply evolved in the only way that was possible, conforming to the niche created by nature. The organic molecules simply fell into place according to where the laws of physics told them to go.
I feel somewhat stupid for not realizing this a long time ago. Nevertheless, it destroys any lingering doubts that biological system are too complex to be explained by evolution.