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