Nick Pyenson studies whales--all cetaceans, in fact. Whales include the largest animals that have ever lived on Earth. We've interacted with them for much of our history.
But because they spend most of their lives underwater, and mostly don't have any regular need to be close to shore, we know surprisingly little about them. Which whales have the most oil or blubber is important for whale hunters, but not exactly a deep scientific insight, taken by itself. It doesn't tell us anything about how whales evolved, where they are and what they're doing in the great majority of their time that isn't spent anywhere near humans, or what their likely future in a changing world may be. Nick Pyenson has spent his professional life trying to answer those questions.
