About Florence M Rollwagen Expertise I can answer questions in biology, microbiology and immunology on the undergraduate or graduate level. I can also address medical and health concerns regarding alternative medicine, autoimmune diseases (lupus, MS) liver disease and intestinal problems.
Experience I have over 20 years experience in research and teaching at the medical/graduate level, and 5 years teaching college biology and microbiology. My expertise is in microbiology and immunology, specifically the biology of cytokines and soluble immune response modifiers. I also carried out original research in blood substitutes and shock/trauma.
Organizations American Association of Immunologists (AAI)
American Association for the Advancement of Science (AAAS)
Publications Journal of Experimental Medicine, Journal of Immunology, Cytokine, Shock, Experimental Hematology
Education/Credentials BS biology 1966
MS biology 1968
PhD immunology 1979
I'm an undergraduate working towards a degree in Ecology and Evolutionary Biology. Through my pleasure reading I've started learning how the idea of using proteins as molecular clocks works. The method seems to hinge on the assumption that mutations in the measured protein sequences occur at a fairly constant rate. Why would it be constant? I'm also curious to know how this method has been refined over the decades and how accurate it is today.
Any knowledge you can give me or related sources you can point me to will be much appreciated. Thank you.
Answer Hi Tom: Thanks for your question.
It's true, the use of molecular clocks as evolutionary tools has become more refined over the years. It is still subject to some controversy, however, since, as you pointed out, why do we expect proteins to change at a constant rate?
In fact, different proteins change at different rates, and to correlate them with evolutionary changes requires some assumptions.
This is a complex and somewhat controversial theory, it has worked for some divergences among species, but requires additional testing and corroboration with other timelines.
Hope this helps, write back if you have more questions.
