For more than a century biologists made great strides in understanding the complex tapestry of life by tracing the smaller and shorter threads in its many patterns. This reductionist approach, which breaks complicated processes into their component parts to understand them better, has produced extraordinary advances. We take it for granted, for example, that DNA molecules—and not proteins—carry our genetic information, but that was a matter of huge debate and study in the early 20th century. (Back then, DNA seemed much too simple a molecule, chemically speaking, to be capable of maintaining generations of hereditary information; proteins, on the other hand, were wonderfully complex and seemed more equal to the task.) More recently, neurologists have traced the formation (and pruning) of countless connections among neurons in the brain that make the process of learning resemble growing a garden more than programming a computer.

Today's researchers, however, are increasingly hitting the limits of reductionism. They realize that you cannot truly understand life without also having a way to deal with its complexity. Genes do not exist in isolation—they affect one another and, somewhat inconveniently for study, are affected by other molecules and chemicals. We understand that our consciousness—our awareness of our own existence and ability to see ourselves as individuals—must somehow emerge from those many, many connections in our brains, but we do not yet know how.

A new field of study—called systems biology—allows investigators to study more of this complexity without going crazy. It requires biologists to be just as comfortable working with computers as they are working with microscopes. And it offers tremendous promise. Alan Aderem, a co-founder of the Institute of Systems Biology in Seattle, Wash., makes a strong case for the idea that systems biology will help us finally make successful vaccines against certain illnesses that have so far resisted our efforts, including AIDS, tuberculosis and malaria. His article, "Fast Track to Vaccines" appears in the May 2011 issue of Scientific American.

Indeed, a systems biology approach is being introduced in some medical schools, colleges and even high schools. Watch this video, from Virginia Commonwealth University, to get a general idea of what systems biology is all about and how high school biology students are learning to use computers to make sense of the most intricate aspects of life.