Abstract
Attempts over the past 30 years to explain geographic variation in the
strength of herbivore pressure gave rise to the latitudinal herbivory
hypothesis. However, this long-standing hypothesis has rarely been
tested using community-level data.
In this study, we selected 43
grassland sites along a 1,500-km latitudinal gradient (c . 27°N to
39°N) on the Qinghai-Tibetan Plateau. We calculated community-wide
herbivory at each site by summing herbivory across plant species
weighted by the biomass of each species; we then investigated how
abiotic and biotic latitudinal correlates drove community-wide herbivory
via their effects on intraspecific herbivory variability and species’
turnover. We found that community-wide herbivory decreased with
latitude, mirroring intraspecific herbivory variability. Furthermore,
intraspecific herbivory variability was driven by climatic factors, but
not edaphic or plant community factors. Overall, our study highlights
the importance of considering both intraspecific herbivory variability
and species’ turnover for predicting how climate change will alter
community-wide herbivory.
Keywords: alpine meadow, community composition, community
weighted mean, plant defense, plant-herbivore interactions, latitudinal
herbivory hypothesis