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