Holly A. Ewing, associate professor of environmental studies at Bates College in Lewiston, talks with senior Miles Schelling about his presentation at the 15th Mount David Summit on Friday. More than 380 students presented research posters, short talks, panel discussions, a photography exhibition, literary readings and video screenings. “True mastery of a subject or topic includes not just knowing all the key questions and answers, but being able to effectively communicate this information to a lay audience, and to persuade that audience about the significance of one’s work,” said Matt Auer, vice president for academic affairs and dean of the faculty.