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