When water runs out, some creatures refuse to stay put and wait.
Most fish stranded at low tide flop around helplessly. But one species calmly strolls to deeper water using its fins like legs. What type of animal is it—not what you'd expect to see taking a walk?
A shark. The epaulette shark lives in shallow reefs and evolved to walk across exposed rock when tides drop.
Some "walking fish" don't actually walk—they do push-ups. What body part does one species use to prop itself up and shove forward?
Its gills. The climbing gourami has spiny gill covers that work like crutches, letting it jerk along the ground.
What surprising ability do mudskippers show off that most fish would never attempt?
Climbing trees. These land-adapted fish can survive days out of water and actually scale mangrove trees, though not very high.
What does the tripodfish do on the ocean floor that looks like a person waiting for a bus?
Stands on three fins. This deep-sea fish props itself up like a tripod and hunts from this stationary position on the seafloor.
A 375-million-year-old fish fossil shocked scientists because it had something no fish has today: a flexible neck. What could this ancient fish do that modern fish cannot?
Turn its head. Fish must swivel their whole body to look around, but this creature (called Tiktaalik) could move its head independently. That's a key step toward hunting on land.
