Trophic Downgrading of Planet Earth

@article{Estes2011TrophicDO,
  title={Trophic Downgrading of Planet Earth},
  author={James A. Estes and John Terborgh and Justin S. Brashares and Mary E. Power and Joel Berger and William J. Bond and Stephen R. Carpenter and Timothy E. Essington and Robert D Holt and Jeremy B. C. Jackson and Robert J. Marquis and Lauri Oksanen and Tarja Oksanen and Robert T. R. Paine and Ellen K. Pikitch and William J. Ripple and Stuart A. Sandin and Marten Scheffer and Thomas W. Schoener and Jonathan B. Shurin and Anthony R. E. Sinclair and Michael E. Soul{\'e} and Risto Virtanen and David A. Wardle},
  journal={Science},
  year={2011},
  volume={333},
  pages={301 - 306}
}
Until recently, large apex consumers were ubiquitous across the globe and had been for millions of years. The loss of these animals may be humankind’s most pervasive influence on nature. Although such losses are widely viewed as an ethical and aesthetic problem, recent research reveals extensive cascading effects of their disappearance in marine, terrestrial, and freshwater ecosystems worldwide. This empirical work supports long-standing theory about the role of top-down forcing in ecosystems… 
Trophic Cascades
In many ecosystems, apex consumers (top predators) play a crucial role in food web dynamics. Their top-down impacts are known to spread downwards through the food webs in a cascading fashion. Trophic
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