You are currently viewing the abstract.AAAS login provides access to Science for AAAS members, and access to other journals in the Science family to users who have purchased individual subscriptions.Log in via OpenAthens.Log in with your institution via Shibboleth.Download and print this article for your personal scholarly, research, and educational use.Buy a single issue of Science for just $15 USD.As humans age, we prioritize established positive friendships over the new, but risky, socializing we do when we are young. It has been hypothesized that this shift may come as our own sense of...…You are currently viewing the abstract.AAAS login provides access to Science for AAAS members, and access to other journals in the Science family to users who have purchased individual subscriptions.Log in via OpenAthens.Log in with your institution via Shibboleth.Download and print this article for your personal scholarly, research, and educational use.Buy a single issue of Science for just $15 USD.As humans age, we prioritize established positive friendships over the new, but risky, socializing we do when we are young. It has been hypothesized that this shift may come as our own sense of...WW…