Which mammal has up to 260 teeth?

The spinner dolphin is the mammal that can have up to 260 teeth. Its slender jaws contain many small, sharply pointed teeth—an adaptation for gripping slippery fish and squid in open water.

Spinner dolphins belong to the genus Stenella and are famous for leaping from the sea and rotating repeatedly around their body axis. They live in tropical and subtropical oceans, often traveling in large social groups.

A common mix-up is assuming that the animal with the most prominent teeth must have the greatest number. Narwhals have a famous tusk, while giant armadillos have strong teeth, but neither matches the spinner dolphin’s unusually high tooth count. Gray whales are baleen whales and filter-feed, so they have no functional teeth.

The tooth count can vary among individuals, and “up to 260” refers to the upper reported total rather than a fixed count for every spinner dolphin.