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