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