Reinventing Discovery - Michael Nielsen [63]
Services are being developed to mine this nascent biological data web, sort of a Google-for-biology, able to quickly answer complex questions about life. Imagine a world of the future where the biological part of the data web has flourished. Imagine having the genome of newborn children immediately sequenced, and then correlated with a giant database of public health records to determine not just what diseases they’re especially vulnerable to—an old trope of science fiction—but also what environmental factors might influence their susceptibilities to disease. “Your son has an 80 percent chance of developing heart disease in his 40s if he’s sedentary in his 20s and 30s. But with three hours of moderate exerce each week that probability drops to 15 percent.” As problems manifest, special drugs can be created, with their design tailored specifically to individual genetic makeup and past medical history.
Today, the biological data web is just a prototype. Life has tremendous complexity at many different levels, and we are just beginning to map out the biological world. Just settling the basic conceptual categories is challenging. Take the notion of a gene. Until recently, students were taught that a gene is part of the DNA that codes for a protein. That seems simple enough. But, in fact, what scientists mean by a gene is changing, as we come to better understand the relationship between DNA and proteins. The early insight that genes code for proteins is incomplete. We now know that the same sequence of DNA can sometimes be transcribed in different ways, into different proteins. At the same time, a single protein may be formed by transcribing DNA from several disconnected parts of the genome, sometimes even from genetic material on different chromosomes. These are just two of the many ways in which our notion of genes is currently changing. More generally, as our understanding of biology improves, many fundamental concepts are being redefined. And when that kind of redefinition happens it can have profound implications for the way we represent knowledge. It’s easy to imagine at some point in the future a need to radically restructure our databases of knowledge, as we learn that our old conceptual schemas are wrong, and must be updated.
What the Data Web Will Mean for Science
As the data web flourishes, it will transform science in two ways. The first way will be to dramatically increase the number and variety of scientific questions that we can answer. We’ve already seen how the SDSS has enabled thousands of new questions in astronomy to be answered. The more data sources available, and the more richly they’re linked, the more dramatic the effect will be. Think of the way Google’s search data and the CDC flu data were combined. With either data set alone it’s difficult to answer the question “Where is the flu happening, right now?” But when you have both data sets, you can answer that question. The result has a magical, free-lunch quality: combine two data sets and not only can you answer all the questions originally answered by those data sets, you can also answer surprising new questions that emerge from relationships between them. As the data web grows, so too will the number and variety of questions that can be asked. In some sense, the questions you can answer are actually an emergent property of complex systems of knowledge: the number of questions you can answer grows much faster than your knowledge. And the data web aspires to contain all the world’s knowledge.
The second way the data web will transform science is by changing the nature of explanation itself. Historically, in science we prize explanations that are simple. Many of our greatest theories have a rabbit-out-of-the-hat quality, explaining many apparently different phenomena through a single core idea. For example, Darwin’s theory of evolution by natural selection has one simple idea at its core, yet it is an astonishingly powerful framework for understanding the evolution of life. As another example, Einstein’s general theory of relativity has been