A visit to the library, once commonplace, may seem a quaint custom these days. The library now comes to us. Yet something may be left behind—a huge trove of historical writing. “Where our ideas come from has been lost, especially in an age when we don’t read anything that’s not available in digital form on PubMed,” said Christopher A. Walsh, the Bullard professor of neurology at HMS and Beth Israel Deaconess Medical Center.
A recent lecture by the Nobel-prize winning scientist Paul Nurse was intended to change that. The talk, which Walsh introduced, was the first in the new Leaders in Biomedicine series sponsored by the MD–PhD program. Those fortunate enough to find a seat in the packed NRB auditorium on March 15 were treated to a tour of four great ideas in the history of biology—the cell, the gene, evolution by natural selection, and life as chemistry.
A masterful and genial storyteller, Nurse plunged back in time, illustrating each idea with pictures and anecdotes. He attributed the first idea, that of the cell, to the invention of the microscope. The instrument offered up secrets to such naturalists as Robert Hooke who, in 1665, observed fine pores or “cells” in a sliver of cork. Anton van Leeuwenhoek improved the technology. “Soon everybody was looking at cells,” said Nurse, who is president of Rockefeller University.
The middle of that century saw the birth of the second idea, the gene. Nurse gave full credit for the concept to Gregor Mendel. “Unlike most biologists of the day, he took a quantitative approach,” Nurse explained. He also hit upon the right model organism, the sweet pea. And yet Mendel’s “beautiful piece of work”—which was widely circulated, some say even to the great Charles Darwin—was entirely ignored. “Nobody took any notice of it,” Nurse recounted, until the turn of the 20th century.
Darwin’s primary achievement, of course, was to discover the concept of evolution by natural selection. “It’s probably the greatest idea in biology,” said Nurse. Yet the concept of change over long periods of time was something the young Charles learned from his grandfather, Erasmus Darwin. Clearly taken with the elder Darwin, a well-known, if idiosyncratic, physician and naturalist, Nurse described how Erasmus wrote his theories in rhyming couplets and had engraved on his carriage the then blasphemous slogan, “Everything from shells.” “He had to wipe out the motto from his coach after the vicar told rich patients they would be wicked to go to him,” said Nurse.
Antoine Lavoisier, an inventor of the idea that life is chemistry, made an even bigger sacrifice, though not for science. In his day job, Lavoisier was a tax collector for the Ancien Régime—two reasons to be reviled. In 1793, he was guillotined. While alive, he took a special interest in winemaking and proposed that fermentation was the result of a chemical reaction. Louis Pasteur, also a wine aficionado, having shown that bacteria and yeast produced the chemicals required for fermentation, argued that the chemicals were actually necessary for the life of the single-celled organisms.
Though biologists have spent much of the 20th century outlining the chemical reactions going on inside the cell, the time may have come to move on to understanding how individual reactions give rise to complex biological properties, such as sensation, adaptation, reproduction, community, and self-organization. “We need to move beyond simply describing chemical and physical processes,” Nurse asserted. The problem, he said, falls under the rubric of biological organization, a concept that touches on systems biology. “It could make some headway in being a great idea in biology, but I’m not sure.”
For that to happen, biologists might need to learn a new language, that of information processing. “We tend to live in a commonsense world,” Nurse explained. “Twenty-first century biology may have to move into a stranger world, a more abstract realm. Thinking in terms of information processing is certainly worth considering.”
