The body of a land plant is often covered with a waxy to prevent dessication.

Cuticle

Explanation:

Cuticle is the waxy stuff that basically prevents dehydration in plants by preventing water loss through transpiration.

the reason the two sea urchins don't compete with each other for food, resources, etc. is because the urchins have adapted to the environment but they have also adapted to each other. this is most likely because the genes of the sea urchins.

i need an image of the diagram