I think groundbreaking theories just aren't as obvious anymore because many of the big general questions have been answered and with these answers, disciplines

I think groundbreaking theories just aren't as obvious anymore because many of the big general questions have been answered and with these answers, disciplines are constantly dividing and subdividing. Therefore, the great ideas of today don't seem as far reaching. Take evolution, for example - pioneered back when the study of "biology" was mostly just taxonomy and natural history; it now has applications in the vast array of modern biological sciences, including ecology, medicine, genetics, and even computing. There are some great movements in science today that wouldn't have been possible in the past. Bioinformatics, working with huge amounts of genomic data, is one example - how about the Human Genome Project, which was completed in the last decade? Another is James Brown's "macroecology," the idea of using statistics and huge amounts of data to learn about general patterns in the world at enormous temporal and spatial scales (http://en.wikipedia.org/wiki/Macroecology http://en.wikipedia.org/wiki/Macroecology) and answer questions like "what effect would climate change have on the world?" And, depending on how old you are, the potential global application of immunology to eradicate infectious diseases such as smallpox and polio.