churn in Business English. churnnoun [ U ] Preventing customer churn is a major concern for mobile service providers, since 20-40% of customers leave their providers in a given year. Employee churn for new hires increased by 33% for the third straight year.
For 18 months, the baby nurses while its mother is on land, or it swims underwater to suckle. When it dives, the calf closes its nose and ears to block out water. All hippos have this ability. They also have membranes that cover and protect their eyes while they are underwater.
But a pilot whale was noted as having six minutes of REM in a single night. To avoid drowning during sleep, it is crucial that marine mammals retain control of their blowhole. The blowhole is a flap of skin that is thought to open and close under the voluntary control of the animal.