Science’s inconvenient (but interesting) uncertainties

Earth sciences reporter Thomas Sumner recalls seeing the documentary film An Inconvenient Truth when he was in high school. The climate science presented in the movie didn’t surprise him too much — a science-minded student, he had already read about many of the issues. But, he says, the film started a broader dialog about global warming.

“People started caring,” he says, noting that he remembers his own family talking about it (and not always harmoniously) at the time. Revisiting the dramatic predictions made in the film proved an interesting journey for Sumner.

“The main criticism I heard was that the film had watered down the science,” he says. Climate science is amazingly complex, and so is modeling effects of change — from how much sea level might rise to how a warming climate could alter hurricane patterns. Even more striking to Sumner were the sheer number of uncertainties that remain. Those uncertainties are not about whether the climate is changing, but about the details of what such changes will mean for the oceans, the atmosphere and the living things on land — and when the various dominoes might fall. Telling the future is hard, especially about interrelated complex systems, but as Sumner reveals in his story, scientists have made steady progress in the last decade.

Another interesting point is the documentary’s (and Al Gore’s) role in politicizing climate science, which is fair to assume was one of the aims. “Gore was polarizing,” Sumner says. “He created a conversation about global warming, but he also cemented it as a political issue.”

Teeth and gums are neither political nor talked much about. But, as contributing correspondent Laura Beil reports, scientists studying a possible role for gum disease in what ails the body must contend with a slew of uncertainties, not unlike those faced by climate scientists. The bacteria that cause gum disease, some studies find, can travel to the arteries, heart, brain and other sites where they can cause havoc. Not all studies agree, and proving the oral bacteria–disease link beyond a doubt may not yet be within scientists’ grasp. But the fix is relatively simple, even if avoided by many: frequent flossing and regular visits to the dentist.

Keeping things simple was the underlying goal of the team of scientists attempting to build, from scratch, a synthetic organism with the least possible number of genes, as Tina Hesman Saey reports. After many tries, the effort succeeded, but not without first humbling the researchers involved. In the initial attempts, their computer-designed minimal genomes didn’t take. What ultimately worked was putting back some of the unknowns — genes with no known cellular job to do. Only then did the DNA inserted into the shell of a microbial cell yield a synthetic microbe capable of growing and reproducing.

Telling a good story about complex science, whether in a film or in a report on the latest research, requires some simplification. But sometimes the most interesting part lies in the uncertainty.