Department of Integrative Biology, Department of Statistics, University of California, Berkeley, CA 94720, USA and Department of Biology, University of Copenhagen, Copenhagen 2200, Denmark.|Department of Integrative Biology, Department of Statistics, University of California, Berkeley, CA 94720, USA and Department of Biology, University of Copenhagen, Copenhagen 2200, Denmark.|Department of Integrative Biology, Department of Statistics, University of California, Berkeley, CA 94720, USA and Department of Biology, University of Copenhagen, Copenhagen 2200, Denmark.|Department of Integrative Biology, Department of Statistics, University of California, Berkeley, CA 94720, USA and Department of Biology, University of Copenhagen, Copenhagen 2200, Denmark.