On the beach
Subtidal area only
Both intertidal area and subtidal areas
Intertidal area only
Because a sea urchin's egg is relatively big
Because sea urchins have large numbers of eggs
Because the eggs make great omlettes
Because sea urchins have large numbers of relatively big eggs
Other sea urchins
Algae
Sea cucumbers
Small fish
Dome
Porcupine
Pentamerous
Toothpick
Feet
Spine
Nose
Mouth
Strongylocentrotus
Echinoderms
Purpuratus
Animalia