North America
Australia
Asia
Antarctica
The savanna gets a fair amount of rain, at least 20 inches a year.
They have thorns
They have toxic chemicals
Ants protect them
A combination of the above defenses
Winter and summer
Spring and summer
Winter and fall
Dry and wet
Tundra
Grassland
Desert
Temperate forest
All of the above
Developing fire-resistant cover
Having deep roots
Growing quickly
They avoid each other as much as possible
They eat different foods
Their territories don't overlap
They all migrate in different directions