This principle is the field of human genetics. It was Mendel whose meticulous process of research using pea plants applied mathematical models to biological inheritance. Although some of Mendel's findings with pea plants can't be applied to humans, much can, and today's geneticists still use Mendel's three principles to explain genetic inheritance.
The dominant gene is more likely to be passed down, the recessive gene may skip a generation and the individual with this gene may be a carrier, his or her own children not displaying the phenotype, but passing the gene to the next generation. It is more in the work of Richard Dawkin (the Selfish Gene) that suggests only genes ultimately useful to the human race are retained. Generally it is accepted that we are continually evolving and that our environment can also cause ultimate change.