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