Imagine you are a blue whale swimming up the California coast, as you do every spring. You are searching for krill in the Santa Barbara Channel, a zone that teems with fish, kelp forests, seagrass beds and other undersea life, but also vibrates with noise from ship traffic. Suddenly, the noise gets louder.
You start to make a slow, shallow dive, but without much urgency – after all, your species evolved over millions of years without this mysterious noise, so why would you know what to do when you hear it? A minute later, you are fatally struck by a container ship.
