Over the course of its history, the LGBT community has adopted certain symbols for self-identification to demonstrate unity, pride, shared values, and allegiance to one another. These symbols communicate ideas, concepts, and identity both within their communities and to mainstream culture. The two symbols most recognized internationally are the pink triangle and the rainbow flag. Letters and glyphs Gender symbols The female and male gender symbols are derived from the astronomical symbols for the planets Venus and Mars respectively. Following Linnaeus, biologists use the planetary symbol for Venus to represent the female sex, and the planetary symbol for Mars to represent the male sex. Two interlocking female symbols (⚢) represent a lesbian or the lesbian community, and two interlocking male symbols (⚣) a gay male or the gay male community. These symbols first appeared in the 1970s. The combined male-female symbol (⚦) is used to represent androgyne or transgender people; and when additionally combined with the female (♀) and male (♂) symbols (⚧) it indicates gender inclusivity, though it is also used as a transgender symbol. Lambda In 1970, graphic designer Tom Doerr selected the lower-case Greek letter lambda (λ) to be the symbol of the New York chapter of the Gay Activists Alliance. The alliance's literature states that Doerr chose the symbol specifically for its denotative meaning in the context of chemistry and physics: "a complete exchange of energy–that moment or span of time witness to absolute activity". The lambda became associated with Gay Liberation, and in December 1974, it was officially declared the international symbol for gay and lesbian rights by the International Gay Rights Congress in Edinburgh, Scotland. The gay rights organization Lambda Legal and the American Lambda Literary Foundation derive their names from this symbol. Plants and animals In 19th-century England, green indicated homosexual affiliations, as popularized by gay author Oscar Wilde, who often wore a green carnation on his lapel. According to some interpretations, American poet Walt Whitman used the sweet flag plant to represent homoerotic male love because of its phallic connotations. The term , "rose" in Japanese, has historically been used in Japan as a pejorative for men who love men, roughly equivalent to the English language term "pansy". Beginning in the 1960s, the term was reappropriated by Japanese gay media: notably with the 1961 anthology , a collection of semi-nude photographs of homosexual writer Yukio Mishima by photographer Eikoh Hosoe, and later