All data for: Megaherbivore impacts on ecosystem and Earth system functioning: The current state of the science

Megaherbivores (adult body mass >1000 kg) are suggested to disproportionately shape ecosystem and Earth system functioning. We systematically reviewed the empirical basis for this general thesis and for the more specific hypotheses that (i) megaherbivores have disproportionately larger effects on Earth system functioning than their smaller counterparts, (ii) this is true for all extant megaherbivore species and (iii) their effects vary along environmental gradients. We furthermore explored possible biases in our understanding of megaherbivore impacts. We found that there are too few studies to quantitatively evaluate the general thesis or any of the hypotheses for all but the African savanna elephant. Following this finding, we performed a qualitative vote counting analysis. Our synthesis of this analysis suggests that megaherbivores can elicit strong impacts on e.g. vegetation structure, and biodiversity and all the elephant species promote seed dispersal. We were however unable to ...