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