Saturday Citations: Chatbots chat about suicide; ancient concrete recipes; depression and brain morphology

This week, researchers at the University of Albany reported an extreme size difference between early human males and females, suggesting intense competition among males. Krill are so overfished in Antarctica this year that the Commission for the Conservation of Antarctic Marine Living Resources may trigger an unprecedented early closure of the fishery. And researchers report early behaviors that signal upcoming divorce between paired songbirds long before the breeding season.