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Hey there!

I'm Mark "Tough Guy" Holton, and I live in a tree. When I'm not in my backyard playing with my friends, you can often find me climbing rocks or just playing on jungle gyms after work. Heck, I even teach people how to climb. Here's one of my students. (Say hello to Sara!)

You can often find me in my lab, but my lab isn't hip enough to have a homepage. However, right now I'm collaborating with my good buddy Fred, and his group has a homepage. You can also see his lab's page.

Fred and I normally climb at the local climbing gym, but, when it's warm out, we much prefer jungle gyms.

Of course, neither gym climbing nor jungle gym climbing is really appropriate for a guy as tough as I am. Occationally, I like a really spectacular epic.