. . "floor, in its belly.[citation needed] Brain and sensesThe sperm whale's brain is the largest in the world, five times heavier than a human's.The brain is the largest known of any modern or extinct animal, weighing on average about 7.8 kilograms (17 lb),[41][42] more than five times heavier than a human's, and has a volume of about 8,000 cm3.[43] Although larger brains generally correlate with high" . .