• DOI:10.1126/science.1214261
• Corpus ID: 26675232

The Aftermath of Megafaunal Extinction: Ecosystem Transformation in Pleistocene Australia

@article{Rule2012TheAO,
  title={The Aftermath of Megafaunal Extinction: Ecosystem Transformation in Pleistocene Australia},
  author={Susan Rule and Barry W. Brook and Simon Graeme Haberle and Chris S. M. Turney and A. Peter Kershaw and Christopher N. Johnson},
  journal={Science},
  year={2012},
  volume={335},
  pages={1483 - 1486}
}

• S. Rule, B. Brook, +3 authors Christopher N. Johnson
• Published 23 March 2012
• Environmental Science, Geography
• Science

Human Impact? Following the arrival of humans in Australia 40- to 50,000 years ago, many species of large vertebrates rapidly became extinct. By analyzing sediment cores from a site in northeastern Australia, Rule et al. (p. 1483; see the Perspective by McGlone) show that the extinction of the Australian megafauna caused important ecosystem shifts. Prominent among these were a shift from rainforest vegetation to sclerophyllous vegetation and a sustained increase in the incidence of fire. The cores also provide evidence of the cause of megafaunal extinction in Australia, ruling out climate and anthropogenic fire as possible causes while confirming that the extinctions closely followed human arrival. These findings show how landscapes sometimes have been fundamentally changed by the indirect effects of early humans—which underscores the impact that even prehistoric human societies had on natural systems. The extinction of megafauna 40,000 years ago after the arrival of humans led to major changes in vegetation and fire regimes. Giant vertebrates dominated many Pleistocene ecosystems. Many were herbivores, and their sudden extinction in prehistory could have had large ecological impacts. We used a high-resolution 130,000-year environmental record to help resolve the cause and reconstruct the ecological consequences of extinction of Australia’s megafauna. Our results suggest that human arrival rather than climate caused megafaunal extinction, which then triggered replacement of mixed rainforest by sclerophyll vegetation through a combination of direct effects on vegetation of relaxed herbivore pressure and increased fire in the landscape. This ecosystem shift was as large as any effect of climate change over the last glacial cycle, and indicates the magnitude of changes that may have followed megafaunal extinction elsewhere in the world.