1Department of Biology, Drexel University, Philadelphia, PA 19104 USA
2Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138 USA
3Department of Pediatrics, The University of California San Diego, La Jolla, CA 92093 USA
4Department of Medicine, Institute of Diabetes, Obesity and Metabolism, University of Pennsylvania, Philadelphia, PA 19104 USA
5Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104 USA
6School of Biomedical Engineering, Science and Health systems, Drexel University, Philadelphia, PA 19104 USA
7Department of Biology, Calvin College, Grand Rapids, MI 49546 USA
8Laboratory of Social Evolution and Behavior, The Rockefeller University, New York, NY 10065 USA
9Department of Science and Education, Field Museum of Natural History, Chicago, IL 60605 USA
10Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
© The Author(s) 2018
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