You are reading a scientific paper regarding the relationships of the anatomical and behavioral characteristics of chimpanzees and their implications for early hominid evolution. You note that the authors refer to human ancestors as hominids. This implies that the researchers are relying on:

answer: grassland biomes are closer to the equator and receive more rain.

grasslands are biomes that are dominated by grasses rather shrubs and trees. savanna are biomes that exhibit grasses, shrubs and small tree as vegetation. grasslands are located near the equator of the earth. these are found in north america. savanna biomes are found in africa, south america, australia and india. grassland exhibit moderate climatic conditions, it receives   amount of rainfall higher than savanna.   therefore, savanna exhibit dry and hot climatic conditions.