of years ago, jellyfish were trapped in this lake after a submerged
reef rose from the sea, creating a landlocked saltwater lake.
In this lake, the jellyfish have adapted to the new conditions
by losing their sting. They have eight primitive eyes and algae
that live within their cells. These algae are what the jellyfish
live on. Twice each day, the jellyfish in the lake swim from
one side to the other. The jellyfish do this to get sunlight
to their internal algae so that the algae can grow. At night
the jellyfish swim to a lower depth where the water is rich
in nitrogen. The nitrogen also sustains the algae population.
The jellyfish has only one main predator in this lake -- the
sea anemone. Jellyfish can be stung, trapped, and killed by