This is an important topic in my Biology classes.
Females often prefer to mate with the most flamboyant males. Their choice may be based on a complex interaction between instinct and imitation ......by Lee Alan Dugatkin and Jean-Guy J. Godin; Scientific American | March 2002
Finding Mr. Right
Over the past 25 years, a considerable body of scientific evidence in support of female choice has accumulated. Females actively choose their mates in a large variety of species--particularly ones in which males are less aggressive and display individual differences in secondary sexual characteristics, such as ornamental plumage or courtship displays. Nevertheless, how and why females select their partners and how mating preferences have evolved remain hotly debated issues among evolutionary biologists.
A choosy female faces two general tasks in selecting a mate. First, she must search for and locate a male. This task can be difficult if the population is sparse or if the danger of predators prevents her from spending a good deal of time searching for a suitable mate. Once she has encountered a male, the female must then decide whether to accept or reject him as a mate. The decision often involves some shopping around. In certain mating systems, females may encounter a group of available males and can compare them on the spot. For example, in early spring, male sage grouse (Centrocercus urophasianus) aggregate "cheek-to-jowl" in temporary communal mating arenas called leks, where they strut their stuff for the females. A female typically observes the displays of a number of males, apparently comparing them before mating with one lucky suitor. She then leaves the lek to nest and raise her brood elsewhere. Of all the potential mates on a lek, a few preferred males receive the bulk of the female attention.
But males are not always conveniently displayed like chocolates in a sampler box. More commonly, females encounter males one at a time. Comparing males in this case is presumably a more challenging cognitive task, as it involves remembering the characteristics of an individual that is no longer in sight. Studies have shown that females can rank the characteristics of sequentially presented males.
Theo C. M. Bakker and Manfred Milinski of the University of Bern in Switzerland found that female three-spined sticklebacks (Gasterosteus aculeatus) will tailor their mate choice to the relative attractiveness of the present and previously encountered males. Females were more likely to show interest in a male if his red nuptial coloring was brighter than the previous male's and more likely to reject a suitor whose coloring was less bright than his predecessor's.
Whether a female chooses her mate from among a dozen dancing grouse or between a pair of crimson fish, she generally selects the most conspicuous contender. Empirical evidence indicates that females commonly prefer male traits that most strongly stimulate their senses. (This evidence has recently been reviewed by Malte Andersson of the University of Göteborg in Sweden and by Michael J. Ryan of the University of Texas at Austin and Anne C. Keddy-Hector of Austin Community College.) For example, when given a choice, female green tree frogs (Hyla cinerea) are preferentially attracted to males that call the loudest and most frequently; female guppies (Poecilia reticulata) to the most brightly colored males; and female mallards (Anas platyrhynchos) to males that court them most frequently. Because of such preferences, males have typically evolved exaggerated secondary sexual traits to attract the opposite sex.
Read the rest here.