Final answer:
The principle that males with large, ornate displays can still successfully mate despite higher fitness costs is known as the handicap principle. This theory, along with the good genes hypothesis, explains why females may choose males with costly traits: they signal superior genetics.
Step-by-step explanation:
The principle that males with large, ornate displays have a higher cost to fitness but still successfully mate despite the large cost relates to the handicap principle. This theory, part of a broader approach known as sexual selection, suggests that only the fittest individuals can afford these costly traits. The handicap principle goes hand in hand with the good genes hypothesis, which argues that such elaborate traits are an honest signal of an individual’s genetic superiority in terms of efficient metabolism or disease resistance. These display traits may increase the male's visibility to predators and reduce his survival chances, but they may also indicate the male's high quality to potential female mates. Thus, despite the risks and high energy costs, females may prefer these males, leading to higher reproductive success for males with such ornate traits.