The sperm whale（抹香鲸）is an astounding creature. It's longer than a semi-truck, weighs more than 90000 pounds and is the largest member of the toothed whale family. It's known to dive 6500 feet in search of food, and to stay down there for longer than an hour at a time.
Perhaps most fantastically, the sperm whale's brain weighs as much as 20 pounds-the biggest of any species on Earth. But when it comes to brains, is size all that matters？There's a lot we are ignorant of the sperm whale's intellectual capacity because it's difficult to carry out neurological testing on such an enormous marine mammal. But some clues point to sperm whales being much smarter than we give them credit for.
A 2021 study published in Biology Letters, for example, looked back to 19th-century historical logbooks from whalers. Researchers found that sperm whales were at first easy to catch but almost immediately, the whales learned how to elude chaser and whaling success dropped by 60 percent. The study suggests that the whales passed information to one another through sound waves to avoid being caught.
Animals that have big brains usually have a few things in common. They usually live long lives; for example, sperm whales can live for 70 years or longer. Additionally, they're capable of complex behaviors and they tend to be more social. Whales may work together to hunt or communicate in a language all their own.
What's more, humans, whales and dolphins all have spindle neurons in their brains. These nerve cells make us capable of deeper thought, such as reasoning skills, memory, communication and adaptive thinking. And like humans, whales have emotional intelligence- meaning they're capable of empathy, grief and sadness. Still, in proportion to（与. . . 成比例）our body size, the human brain is bigger than that of the sperm whale.
Yet there's still so much we don't know about how smart sperm whales really are. And just like the whalers of a century ago, we have likely been underestimating marine mammals, whether large or small, for as long as we've known of their existence.
