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