Sea cucumbers
Small fish
Algae
Other sea urchins
On the beach
Intertidal area only
Subtidal area only
Both intertidal area and subtidal areas
Strongylocentrotus
Animalia
Echinoderms
Purpuratus
Because sea urchins have large numbers of eggs
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
Pentamerous
Porcupine
Toothpick
Dome
Spine
Mouth
Nose
Feet