1. Department of Biology, University of Washington, Seattle, WA 98195, USA;
2. Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195, USA;
3. Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA;
4. Department of Statistics, University of Washington, Seattle, WA 98195, USA;
5. Computational Evolution Group, University of Auckland, Auckland, New Zealand