VERIFIED FACT

Star-nosed moles can smell underwater by blowing bubbles.

Why this sounds fake

Smelling seems to require air in the nose, which should make underwater sniffing a contradiction.

Mammals smell by moving odor-filled air across nasal tissue, which seems useless underwater. Star-nosed moles found a workaround. While diving, they exhale tiny air bubbles onto objects or scent trails, then quickly inhale the bubbles again. The returning air carries odor molecules back to the nose. Experiments showed the method helped them follow underwater scent trails. This does not mean they smell water the way a fish senses chemicals. They are briefly bringing air to the odor and back again. It is snorkel-like olfaction packed into rapid bubble handling.

The Surprise

The bubble is not decoration - it temporarily carries odor information back to the nose.

Hybrid visual: a real star-nosed mole photo beside a diagram of an underwater air bubble loop moving from the nose to an object and back.
The same strange nose can use an air bubble as an underwater smell loop. U.S. Fish and Wildlife Service / Wikimedia Commons · Public domain

1 discovery explored