1. Trinity College, Trinity Street University of Cambridge Cambridge CB2 1TQ U.K.
2. Leverhulme Centre for Human Evolutionary Studies, Department of Archaeology, Fitzwilliam Street University of Cambridge Cambridge CB2 1QH U.K.
3. Institute of Neuroscience Trinity College Dublin Dublin 2 Dublin Ireland
4. School of Psychology Trinity College Dublin Dublin 2 Dublin Ireland
5. Department of Experimental Psychology, Radcliffe Observatory Quarter University of Oxford Oxford OX2 6GG U.K.
6. Pembroke College University of Oxford Oxford OX1 1DW U.K.
7. Department of Psychiatry, Warneford Hospital University of Oxford Oxford OX3 7JX U.K.
8. Department of Ecology and Evolutionary Biology, Corson Hall, Tower Road Cornell University Ithaca NY 14853 U.S.A.
9. Department of Human Evolutionary Biology Harvard University, Peabody Museum, 11 Divinity Avenue Cambridge Massachusetts 02138 USA
10. Psychiatry, University of Helsinki and Helsinki University Hospital PL 590 FI‐00029 Helsinki Finland
11. Department of Psychology and Logopedics, Faculty of Medicine University of Helsinki P.O. Box 6, FI‐00014 Helsinki Finland
12. Institute of Clinical Medicine/Psychiatry University of Eastern Finland P.O. Box 1627, FI‐70211 Kuopio Finland
13. Division of Comparative Medicine Massachusetts Institute of Technology Building 16‐825, 77 Massachusetts Avenue Cambridge MA 02139 U.S.A.