A heavy toll

Trade in wildlife, and their parts, is well recognized for a few key species, such as elephants and rhinos, but it occurs globally, across a wide array of species. Scheffers et al. looked across tens of thousands of vertebrate species and found that one in every five species is affected by trade of some sort. The impacts of trade tend to be concentrated in certain phylogenetic groups, thus the potential for long-term impact on certain lineages is substantial. This analysis allows for prediction of potential for trade where it does not yet occur, facilitating proactive prevention.
Science, this issue p. 71


Wildlife trade is a multibillion dollar industry that is driving species toward extinction. Of >31,500 terrestrial bird, mammal, amphibian, and squamate reptile species, ~24% (N = 7638) are traded globally. Trade is strongly phylogenetically conserved, and the hotspots of this trade are concentrated in the biologically diverse tropics. Using different assessment approaches, we predict that, owing to their phylogenetic replacement and trait similarity to currently traded species, future trade will affect up to 4064 additional species—totaling 11,702 species at risk of extinction from trade. Our assessment underscores the need for a strategic plan to combat trade with policies that are proactive rather than reactive, which is especially important because species can quickly transition from being safe to being endangered as humans continue to harvest and trade across the tree of life.

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Supplementary Material


Materials and Methods
Figs. S1 to S8
Tables S1 to S10
References (3662)


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Published In

Volume 366 | Issue 6461
4 October 2019

Submission history

Received: 25 September 2018
Accepted: 4 September 2019
Published in print: 4 October 2019


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We dedicate this paper to all researchers and park guards who have lost their lives in protecting wildlife from illegal trade. Funding: B.R.S. received financial support from the UF/IFAS Early Career Seed Grant. Author contributions: B.R.S., B.F.O., and D.P.E. conceptualized the idea and methodology, I.L. and B.F.O. collected data, B.F.O. analyzed data, B.R.S. and D.P.E. wrote the original draft, and all authors revised the work. Competing interests: None declared. Data and materials availability: All data related to this work are provided in the supplementary materials.



Department of Wildlife Ecology and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
Department of Wildlife Ecology and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
Department of Biology and Environmental Sciences, Auburn University at Montgomery, Montgomery, AL 36124, USA.
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.


These authors contributed equally to this work.
Corresponding author. Email: [email protected] (B.R.S.); [email protected] (D.P.E.)

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