1. Welcome to the UCMP Web Lift for Geologic Time! Available at: http://www.ucmp.berkeley.edu/help/timeformold.html. Accessed June 7, 2007.
2. Human ancestry. Available at: http://www.archaeologyinfo.com/. Accessed June 7, 2007.
3. Becoming human. Available at: http://www.becominghuman.org/. Accessed June 7, 2007.
4. The evolution of human skin coloration;Jablonski;J Hum Evol,2000
5. Becoming bipedal: how do theories of bipedalization stand up to anatomical scrutiny?;Jablonski,2004