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