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