PEANUT BUTTER CLUB: Presents the video “First Horse Warriors” on Friday, August 30, at noon, in Redfield Auditorium, 45 Water St., Woods Hole. Horse riding played a key role in human expansion and civilization. But when and how did people first master these animals? Scientists use archeology and genetics to uncover clues about the first horse riders and how they shaped the world. Sponsored by the WHOI Visitor Center. Coffee, tea, and cookies served. Donations accepted.