Institute for Behavioral Genetics, University of Colorado, Boulder, USA. sterlingsawaya@gmail.com.|Department of Biochemistry, University of Otago, Dunedin, New Zealand. james.boocock@otago.ac.nz.|Department of Biochemistry, University of Otago, Dunedin, New Zealand. mik.black@otago.ac.nz.|Department of Anatomy, and Allan Wilson Centre for Molecular Ecology and Evolution, University of Otago, Dunedin, New Zealand. neil.gemmell@otago.ac.nz.