Little Data

By Charles Henry posted

So much attention today is focused understandably on “big data.” Scientific disciplines such as astronomy, particle physics, meteorology, and genomics generate petabytes of data regularly, requiring new tools of analysis to discern patterns and trends, and to extrapolate new meaning from such astonishing volumes of information. The humanities also must confront the challenge of data at a scale that cannot be read or interpreted by traditional methods and tools. A recent article in the New York Times on research using the Old Bailey database—numbering nearly 200,000 transcripts and 127 million words, covering London trails from 1674-1903—described the sequence of legal reinterpretations of various crimes over the centuries. This insight was made possible by digital tools and computational extrapolation used to analyze the vast database, an intellectual discovery that would be impossible for a human being reading the texts: the data is larger than several lifetimes of perusal.

We should, however, keep in mind examples of “little data,” small amounts of information that can nonetheless change the way we view the world and interpret our place in it. Two examples are especially intriguing: the work by Luis and Walter Alvarez on the extinction of dinosaurs, and more recently the brief emergence of ancient landscapes in Wales and England.

For decades, beginning in the 1950s, scientists had speculated on the reason for the great extinction of dinosaurs at what is called the Cretaceous-Tertiary (K-T) Boundary in geological time, approximately 65 million years ago. One of the theories posited that a giant asteroid hit the earth and caused enormous disruption: initially searing temperatures, followed by years of a cold, nearly sunless climate. There was no evidential proof for this hypothesis until Luis and Walter Alvarez (a father and son team) began to look at geological strata that formed during the period of extinction. (1)

They discovered that in three sites there was an inordinate amount of iridium encased in the ancient rock. Since iridium only occurs on earth from a source from outer space, the Alvarez team deduced that an asteroid hitting the earth was indeed the causal event that wiped out the large reptiles, sparing the smaller mammals that could shelter from the deadly climate fluctuations.

They published their research in 1980, greeted by a chorus of skepticism. Over time, many other examples of the iridium layer have been discovered, the location of the asteroid's impact on earth determined (the Yucatan Peninsula), and today there is wide acceptance of the extraterrestrial cause of the K-T Boundary extinction. Our understanding of one of the most cataclysmic events in earth's history, an event that literally changed the course of life, originated from a very small collation of data—just three examples—of isolated rock formations.

The second example of little data involves the serious flooding that has occurred in Britain over the past few years. The heavy volume of running water has exposed ancient riverbeds and other landscape features from the distant past. The forest of Borth in Wales is one such phenomenon. It was buried about 5,000 years ago as the climate warmed considerably and the sea levels rose swiftly. The recent torrential rains washed away the silted covering temporarily, exposing the locally mythologized stumps of the ancient forest. This revelation allowed scientists to see for the first time the evidence of a fairly extensive human presence in the forest of Borth, prompting speculation on the human response to the devastation of the climate change that flooded the woods and would have wiped out any human settlement in the region: speculation with a decidedly contemporary context.

Across England, at Happisburgh in Norfolk, a more remarkable discovery was made. Again, floods revealed extremely ancient riverbeds and shorelines. At Happisburgh a footprint was detected in the exposed mud, especially startling since the clay incasing the foot impression was 900,000 years old. Knowing the waters would again return and silt over the print, scientists lifted it along with a block of surrounding clay for further examination. The footprint proved that what is today England was inhabited by a human species nearly a million years ago, resetting the clock of human migration in the North Sea region back an additional 200,000 years: another marvelous example of how so little data—in this case a footprint about to vanish back into the distant past—can tell us so much.

Alvarez, L.W., Alvarez, W., Asaro, F., and Michel, H.V. (1980). "Extraterrestrial cause for the Cretaceous–Tertiary extinction." Science 208 (4448):1095–1108. For a more detailed account of Alvarez's work in the context of the history of the science of extinctions, see Elizabeth Kolbert, The Sixth Extinction: An Unnatural History. Henry Holt and Co., 2014.