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