1. School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA.
2. Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA.
3. Gunung Mulu National Park, Sarawak, Malaysia.
4. Institute of Biodiversity and Environmental Conservation, Universiti Malaysia Sarawak, Sarawak, Malaysia.