Answer:
Grunion (Leuresthes tenuis): life begins at high tide. During summer and spring, thousands of these fish swim up onto sandy beaches (carried in by high tide). This is called a grunion run, and it occurs ta night during the new moon and full moon when the tide is highest. The females wiggle into the sand and lay thousands of eggs as the males deposit sperm around them. Afterward, they are swept back into the sea. The spawning is timed so exactly that it occurs only on the second, third, and fourth days that follow a new or full moon. After the grunion eggs are fertilized, they incubate for two weeks until the next new or full moon occurs.
Horseshoe Crab (Limulus polyphemus): during late May and early June, vast numbers of horseshoe crabs come together in shallow bays, marshes, and inlets along the Atlantic and Gulf coasts, waiting to come up on the beaches to spawn. The signal to begin is provided by the moon. During the new and full moons, when tide is highest, the crabs come ashore. The female produces a cluster of tiny eggs on her abdomen, and the eggs are fertilized by the male's sperm, and then deposited out in the sand by the female. The next two weeks, the eggs incubate until they hatch during the next full or new moon. When the high water reaches the eggs, they hatch and go out into the ocean.
Explanation: