William J. Bond
- Published in print:
- 2019
- Published Online:
- September 2019
- ISBN:
- 9780198812456
- eISBN:
- 9780191850318
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198812456.003.0008
- Subject:
- Biology, Ecology, Biodiversity / Conservation Biology
Can herbivores account for the widespread occurrence of open ecosystems? Some suggest that Pleistocene megafauna did so, and large mammal herbivory is still important in some regions today. Exclosure ...
More
Can herbivores account for the widespread occurrence of open ecosystems? Some suggest that Pleistocene megafauna did so, and large mammal herbivory is still important in some regions today. Exclosure studies have been widely used to test herbivore impacts on trees, but global patterns of the ‘brown world’ are not readily seen from satellites. Areas of mammal consumer dominance occur in cool temperate/boreal regions (e.g. Tibetan montane grasslands) and savannas in Africa, but not in those in Australia or South America. Herbivores vary in their impact on openness of vegetation because of differences in body size, feeding mode, predator avoidance behaviour while plants also differ in their defences and accessibility. Unlike fire, proxies are lacking for how extinct herbivores, even giant sauropods, impacted vegetation. Very few studies deal explicitly with how vertebrate herbivores help create and maintain open ecosystems where climates are suitable for forests, and there is an urgent need to find out more.Less
Can herbivores account for the widespread occurrence of open ecosystems? Some suggest that Pleistocene megafauna did so, and large mammal herbivory is still important in some regions today. Exclosure studies have been widely used to test herbivore impacts on trees, but global patterns of the ‘brown world’ are not readily seen from satellites. Areas of mammal consumer dominance occur in cool temperate/boreal regions (e.g. Tibetan montane grasslands) and savannas in Africa, but not in those in Australia or South America. Herbivores vary in their impact on openness of vegetation because of differences in body size, feeding mode, predator avoidance behaviour while plants also differ in their defences and accessibility. Unlike fire, proxies are lacking for how extinct herbivores, even giant sauropods, impacted vegetation. Very few studies deal explicitly with how vertebrate herbivores help create and maintain open ecosystems where climates are suitable for forests, and there is an urgent need to find out more.