On this week’s Tech Nation, Moira speaks with Marine biologist Dr. Drew Harvell about her new book, "The Ocean’s Menagerie: How Earth’s Strangest Creatures Reshape the Rules of Life." Then, Sameer Sabir, CEO of Brixton Biosciences, explains their new injectable cold therapy in trials for knee pain. And, Erica Dhawan returns to explore the impact of tone in digital communication and why it often goes unnoticed.