Questions about genders ... male/female

[popeyespappy]

Evolution does not necessitate that everything trend towards infinity. What I mean by this is that if an organism is perfectly suited to it's environment, then we wouldn't expect any genetic drift. Obviously no organism is perfectly suited to its environment, so there is always space to improve in some areas. However, if a certain aspect of anatomy or physiology functions very well, then there is very little selection pressure.

Genetic drift within a population doesn't stop no matter how perfectly suited to an environment an organism might be. The DNA of each new generation is going to be different than that of their ancestors. Removing natural selection from the equation by reducing environmental pressure does not stop the gene pool from changing over time. Genetic drift does however tend to reduce variation within the population over time which is a bad thing should there be an environmental change because selection only works if there is variation.