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