Oct. 20, Wednesday -- Stanford biologist Joan Roughgarden will deliver a spirited criticism of the Darwinian concept of sexual selection based on her book, "Evolution's Rainbow: Diversity, Gender and Sexuality in Nature and People." Roughgarden will talk about the underreporting of homosexuality in nature and other topics related to the way scientists conceive gender and sexuality in the natural world. Her speech, sponsored by Women and Gender Studies, begins at 8 p.m. in the Recreation Pool Lodge, UC Davis campus. The talk is free and open to the public. For the 6 p.m. reception and dinner, which are by reservation only, call Women and Gender Studies at (530) 752-4686. The event is part of Gay Pride Week Oct. 18 to 22.