Here's why:

* Similar Climate: Both grasslands and savannas experience distinct wet and dry seasons, with warm temperatures year-round.

* Similar Vegetation: Both biomes are dominated by grasses, with scattered trees or shrubs in the savanna.

* Similar Herbivores: Large grazing herbivores like zebras, wildebeest, and antelope thrive in both environments.

* Similar Carnivores: Predators like lions, leopards, and hyenas are common in both biomes.

While there are some differences (e.g., savannas tend to have more trees and a longer dry season), the overall similarities in climate, vegetation, and animal life make the savanna the closest biome to grasslands.