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Ask Mark Your Questions

ByTom MillerThe Secret Life of Scientists and EngineersThe Secret Life of Scientists and Engineers

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Click here for Mark’s profile.

So we’ve already asked Mark Siddall 10 questions (and you can watch the video). Then we figured you should get a chance. Check out his answers:

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Q: Sophie L.

How is your career as a scientist working at a museum different from a scientist’s life in academia? Why did you choose this path?


A: Mark Siddall

Typically, curatorial positions at Museums of Natural History like AMNH are largely research driven with curation of collections taking the place of teaching responsibilities. That being said, prior to being hired here I was a professor at the University of Michigan where I had had students and taught, among other things, Biology of Sex for non-majors. Though I certainly looked forward to the freedom associated with becoming a Curator, I was reluctant to give up pedagogy entirely. So, very much like other academic environments, I host graduate students (through City University and Columbia University where I am cross appointed) and post-docs in my lab. AMNH has instituted the Richard Gilder Graduate School, so we are now degree-granting in our own right and my teaching responsibilities have re-expanded. I guess the difference is that no one can tell me what to teach, or when to teach. I get to pretty much pick that myself. In my case, I specifically chose this path over a medical degree because I became totally enthralled with biodiversity research while I was an undergraduate student intern. Noteably, I have run the summer NSF-funded Research Experiences for Undergraduates program here for the last decade.

Q: Jamie R.

Did you ever imagine when you were in a kid that you might become “The Leech Man?” What did you think you wanted to be? When did you get “bitten” by the desire to study these blood suckers?

A: Mark Siddall

When I was a kid, and right through to my junior year at the University of Toronto I wanted to be a physician. As an undergraduate intern with Sherwin Desser at UofT in the summer of 1988, I was given the task of elucidating the life-cycle of a single-celled blood parasite of frogs. Because tadpoles had the infection, it had to be leeches. So, I spent the summer collecting leeches and frogs, managed to solve the cycle, and was smitten by the diversity of leeches in Algonquin Park. I never looked back.

Q: Adam

Mark, what is your favorite thing or dish that you like to cook?

A: Mark Siddall

The principle of leech therapy is simple. After certain kinds of surgery, like reattaching a digit, or an ear, the arteries are better at getting blood into the tissue than are the veins in getting the blood out. The veins need more time to heal. The result is that the tissue gets congested with blood, which could clot and lead to loss of the tissue entirely. Put leeches on, they remove the excess blood, the veins have time to heal… presto: tissue saved.

As well, there is a history of use of some leech anticoagulants like hirudin. Before heparin was available, hirudin was used, even for the first ever successful human dialysis treatment. Hirudin is still used for people who react badly to heparin (Heparin Induced Thrombocytopaenia).

If you’d like to learn more about these and other leechy things, check out my blog at

A for maggots, I am not expert, but I do know that one of the points of using maggots is that they will eat away dead tissue leaving healthy tissue alone. In terms of burns, it seems they have been used As for snake bites, my guess is that the issues there are much more acute in terms of the neurotoxins and hematoxins from snake bites, as opposed to the necrosis that can set in over time. A snake bite tended to only with maggots is probably not a wise move.

Q: David C.

Which do you think should take first priority human kindness or scientific experimentation?

A: Mark Siddall

tertium non datur