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