Male sperm whales produce exceptionally powerful slow clicks that may remain detectable across roughly 70 kilometres of deep ocean while maintaining remarkably precise intervals of five to ten seconds.
Researchers propose that the whales might exploit echoes from the seabed or surface as external timing references, effectively using the geometry of their environment to maintain the rhythm rather than relying solely on an internal clock. The communicative purpose remains unresolved, with possibilities including signalling body size to females or rivals, but the physical signalling mechanism is unusually striking.
https://phys.org/news/2026-08-male-sperm-whales-loudest-communication.html
