Identify and discuss three lines of evidence demonstrating the social basis of sexuality.

1) Historical and cultural variations in sexual norms and practices: Different societies and cultures have different attitudes towards sexuality, with some being more conservative and others being more liberal. This suggests that sexual behavior is influenced by social and cultural factors rather than being purely biological.

2) Social construction of sexual identities: The concept of sexual orientation and gender identity is a social construct, meaning that it is shaped by societal norms and expectations. For example, the idea of heterosexuality as the norm and other sexual orientations as deviations is a social construct that has a significant impact on how individuals perceive and express their sexuality.

3) Impact of social institutions on sexual behavior: Institutions such as religion, education, and the media play a significant role in shaping attitudes towards sexuality. For example, religious teachings often dictate moral codes related to sexuality, while educational institutions and the media can influence individuals' understanding of sexual norms and behaviors.

These lines of evidence demonstrate that sexuality is not solely determined by biological factors, but is also heavily influenced by social and cultural forces. This understanding is important for addressing issues related to sexual health, rights, and equality, as it highlights the need to consider the social context in which sexual behavior occurs.