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