Qualifications
When in college, make sure that you take courses in anthropological theory, research methodology, and analytical methods. Once you've learned enough about anthropology in general and have determined what specific aspect of it intrigues you most, study up—hard—on all things biological, medical, linguistic, or whatever your "thing" happens to be.
Don't forget to also take not-directly-related classes like statistics, public speaking, or whatever else may come in handy. Surf Science and Technology (an actual course at Cornwall College in the U.K.)? Hey, if you're planning on specializing in surf culture, it could be useful. Surf's up, dude.
For most jobs, you'll need either a master's degree or a Ph.D. In short, if a scientific consulting firm gives you piles of money to go gallivanting across the globe in order to learn more about the effects of certain diseases in Third World countries, they want to know that you didn't drop out of middle school.