Although the average lifespan of a humpback whale is debated, most research places their life spans at around 40 to 50 years. Humpback whales do not have teeth, so scientists can't use standard methods of testing age in the species.
Humpback whales are baleen whales, which means they have hardened plates that bristle into fine hairs protruding from their upper gums rather than teeth. Researchers test whale age by measuring the number of laminar growth layers in a deceased whale's ear. Because most whales that scientists test are killed by whalers, the actual life span of whales is unclear. If one layer grows annually, which, as of 2014, most researchers believe, then the natural lifespan for whales is probably more than 90 years.