Molecular chronometers are used to determine the course of evolution. Explain in full what these are and how they are used. Why, even with this "tool", is evolution still so complex?
Since this is not my area of expertise, I searched Google under the key words " Molecular chronometers" to get these possible sources:
http://cas.bellarmine.edu/tietjen/Ecology/phylogenetic_classification_and_.htm
(Broken Link Removed)
http://books.google.com/books?id=DL_KQPX3AmIC&pg=PA181&lpg=PA181&dq=Molecular+chronometers&source=web&ots=ERp5LC-nou&sig=I1kBg5W-QaNShsE2RfmHFuygW10&hl=en
http://books.google.com/books?id=tjZT9_wRsXUC&pg=PA9&lpg=PA9&dq=Molecular+chronometers&source=web&ots=nVxLaRcSoc&sig=ECenLMYCbynIVCkF6FY1d1WbYKk&hl=en
(Broken Link Removed)
For your other post and in the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.
I hope this helps. Thanks for asking.