The staccato clicks of sperm whales may sound like meaningless background noise to human ears, but a new analysis suggests they may be part of a communication system with a level of complexity approaching that of our own. According to researchers with Project CETI, a US non-profit working to understand sperm whales, the clicks known as "codas" are more complex than a 2024 study indicated . That earlier work found the sounds had an acoustic resemblance to human vowels. Now, a new paper