Which ballet is notable for the portrayal of a character that can be performed by a performer of the opposite sex?
Cinderella
Cinderella (Prokofiev)
Cinderella (Russian: Золушка , "Zolushka"; French: "Cendrillon") Op. 87, is a ballet composed by Sergei Prokofiev to a scenario by Nikolai Volkov.
 It is one of his most popular and melodious compositions, and has inspired a great many choreographers since its inception.
 The piece was composed between 1940 and 1944.
 Part way through writing it Prokofiev broke off to write his opera "War and Peace".
 The premiere of "Cinderella" was conducted by Yuri Fayer on November 21, 1945 at the Bolshoi Theatre, with choreography by Rostislav Zakharov and Galina Ulanova in the title role.
 "Cinderella" is notable for its jubilant music, lush scenery, and for the comic double-roles of the step-sisters (which can be performed in travesti), more mad than bad in this treatment.
Travesti (theatre)
Travesti (literally "disguised" in French) is a theatrical term referring to the portrayal of a character in an opera, play, or ballet by a performer of the opposite sex.
 Depending on sources, the term may be given as travesty, travesti, or en travesti.
 The "Oxford Essential Dictionary of Foreign Terms in English" explains the origin of the latter term as "pseudo-French", although French sources from the mid-19th century have used the term, e.g. "Bibliothèque musicale du Théâtre de l'opéra" (1876), "La revue des deux mondes " (1868), and have continued the practice into the 21st century.
Homosociality
In sociology, homosociality means same-sex relationships that are not of a romantic or sexual nature, such as friendship, mentorship, or others.
 The opposite of homosocial is heterosocial, preferring non-sexual relations with the opposite sex.
 In group relations involving more than two individuals, the relation can be either homosocial (involving same-sex social relations), bisocial involving social relation with both sexes or heterosocial involving only opposite sex. Childhood gender nonconformity
Childhood gender nonconformity (CGN) is a phenomenon in which prepubescent children do not conform to expected gender-related sociological or psychological patterns, or identify with the opposite sex/gender.
 Typical behavior among those who exhibit the phenomenon includes but is not limited to a propensity to cross-dress, refusal to take part in activities conventionally thought suitable for the gender and the exclusive choice of play-mates of the opposite sex. Heterosexuality
Heterosexuality is romantic attraction, sexual attraction or sexual behavior between persons of the opposite sex or gender.
 As a sexual orientation, heterosexuality is "an enduring pattern of emotional, romantic, and/or sexual attractions" to persons of the opposite sex; it "also refers to a person's sense of identity based on those attractions, related behaviors, and membership in a community of others who share those attractions." Rousette skating
Rousette skating is a skating event, usually organized by schools, student organizations, or sports clubs.
 It has been traditionally held on Valentine's Day.
 Every skater participating in the event is assigned a numbered rosette (a rose-shaped ribbon or bow), blue for males and rose or pink for females.
 The skater's task is to skate around the rink until the person of the opposite sex wearing the same number is found.
 Prizes are awarded to those who find their "mystery partners".
 The event, which includes food and music, serves as a venue for meeting people of the opposite sex. Geodakyan's evolutionary theory of sex
Geodakyan Evolutionary Theory of Sex theory (ETS) (ETS) was proposed by Vigen Geodakyan in 1960-80s.
 This theory has many components related to systemic effects in sex ratios, shapes of phenotypic distributions in male and female phenotypes, sex dimorphism, mutation rates in genotypes, sex differences in birth ratios, mortality rates, and in susceptibility to new diseases.
 Geodakyan started working on the theory in 1965.
 Two main hypotheses of this theory that complement each other are: the principle of conjugated subsystems and the theory of asynchronous evolution.
 These hypotheses relate to the paradox of sexual reproduction and suggest an explanation of why sexual reproduction became the most common way of reproduction among three types of reproduction known in biology: asexual, hermaphrodite reproduction and sexual reproduction.
 The paradox of sexual reproduction (discussed more on the page evolution of sexual reproduction) notes that Hermaphrodite reproduction gives the highest diversity of configurations and an easier mating process than bi-sexual reproduction (such as in humans, when half of the members (males) can’t reproduce and can only diversify the genes).
 Since in bi-sexual reproduction members of species can mate only with the opposite sex, there are fewer opportunities for mating and a lower diversity of outcome of their gene recombinations, in comparison to hermaphrodites.
 Meanwhile bisexual species still have to share food and other resources with members who don’t reproduce (males).
 In spite of these disadvantages of bi-sexual reproduction, paradoxically, most plants and animals shifted from hermaphroditism and gonochorism to sexual dimorphism.
 Why?
 (Figure 1).
 (for comparison of types of reproduction see the review: In 2001, Vladimir Iskrin began refining and expanding on Geodakyan's theory. Drag queen
A drag queen is a person, usually male, who dresses in clothing of the opposite sex and often acts with exaggerated femininity and in feminine gender roles for the purpose of entertainment or fashion.
 Often, they will exaggerate certain characteristics such as make-up and eyelashes for comic, dramatic, or satirical effect.
 While drag is very much associated with gay men and gay culture, there are drag artists of all sexualities.
 There are many kinds of drag artists and they vary greatly in dedication, from professionals who have starred in films to people who just try it once, or those who simply prefer clothing and makeup that is usually worn by the opposite sex in their culture.
 Drag queens can vary widely by class and culture.
 Other drag performers include drag kings, women who perform in male roles and attire, faux queens, who are women who dress in an exaggerated style to emulate drag queens, and faux kings, who are men who dress to impersonate drag kings. Compulsory heterosexuality
Compulsory heterosexuality is the idea that heterosexuality is assumed and enforced by a patriarchal society.
 This refers to the idea that heterosexuality can be adopted by people regardless of their personal sexual preferences.
 Heterosexuality is viewed as the natural inclination or obligation by both sexes.
 Consequently, anyone who differs from the normalcy of heterosexuality is deemed deviant or abhorrent.
 Adrienne Rich popularized the term "compulsory heterosexuality" in her 1980 essay titled "Compulsory Heterosexuality and Lesbian Existence".
 Rich's first concept of compulsory heterosexuality only included women, however, later revisions of the idea have included how compulsory heterosexuality affects men.
 Common examples include the assumption that children will grow up to marry a person of the opposite sex, children must steer away from having friends of the opposite sex, sexual education books that exclusively discuss heterosexuality, the concept of "coming out", religious and secular organizations that assume all members are heterosexual, and believing that if one can pretend to be heterosexual that is better than being homosexual.
 Compulsory heterosexuality is seen as ignorant, a contributor to homophobia by marginalizing non-heterosexuals, treating heterosexuality as the superior default, and decreasing awareness of the large number of people within the population who are not heterosexual. Dual-role transvestism
Dual-role transvestism is the formal diagnosis used by psychologists and physicians to describe people who wear clothes of the opposite sex to experience being the opposite sex temporarily, but don't have a sexual motive or want gender reassignment surgery.
 The International Classification of Diseases (ICD-10) list three diagnostic criteria for "Dual-role transvestism" (F64.1):