Tiny Animals, Big Survival Skills

Vernal pool animals may be small, but they are remarkable survivors.

Fairy shrimp and tadpole shrimp lay eggs that can dry out completely and remain dormant for years—or even centuries—until rain returns. Not all eggs hatch at once, which protects the species if a pool dries too early.

Vernal pools may look temporary and fragile, but the tiny animals that live here are masters of survival. Many invertebrates, like fairy shrimp and tadpole shrimp, have eggs that develop to several thousand cells, then pause in a dormant state called a cyst. These cysts can survive extreme drying, sometimes for hundreds or even thousands of years, and still hatch when the conditions are right. In fact, vernal pool cysts have even survived a trip to the Moon and hatched when returned to Earth!