ACKNOWLEDGMENTS We specifically thank Sharon Chan and Benja-
min Lee for guidance and assistance on this project. We also thank the staff of the National Parks Service for their facilitation and assistance and the government of Singapore for granting us permission to conduct this research. Gregory Engel, Michael Schillaci, and John Sha also contributed to making this project possible. We thank Benjamin Lee for his extensive commentary on earlier drafts of this article. This research was conducted in compliance with the University of Notre Dame IACUC 07-060.