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