You may have seen lions, elephants and snakes in the zoo but if you wanted to see these incredible animals in their natural habitat you’d need to visit a tropical grassland, or a savanna.

But they are vibrant ecosystems, and some, like the African savanna, are home to the animal kingdom's most recognizable fauna.

Savanna consists of scattered trees within a continuous stand of prairie grassland. Fire is common in these systems and the trees are restricted to a few fire-resistant species, primarily bur oaks.

Take the savanna, for example— a transitional biome ... And along the way, they’re disrupting grassland biomes that aren’t used to so many trees. Then those grasses creep into deserts ...