I experienced another birthday recently (celebrated is no longer appropriate; endured is over-dramatic, at least for the time being). Without quantifying too much, let’s just say I can remember Sputnik but not the Korean War.
Why bring it up? My life has, coincidentally, been concurrent with the last half of the 20th century. Plus a bit of the 21st. And this period has been a remarkable one for science. I 've read persuasive arguments that for all the amazing advances in medicine, communications, and transportation that the past 50 or 100 years have witnessed, the greater paradigm shift happened during the industrial revolution. The telegraph, the steam engine, and the transition from farm to factory had a bigger impact on most peoples lives. This may be true, but our understanding of the natural world wasn’t changing at the same rate. The universe described by Newton in the 17th century was the same universe people inhabited at the beginning of the 20th century. Since then, we’ve come light years, literally.
One of the most commonly encountered criticisms of a scientific world view is that science, as a tool for understanding the world, is no more legitimate than almost any other mythological or investigative methodology. On the left, this manifests itself as relativism — the idea that there are no absolute truths, only truth relative to some cultural or intellectual frame of reference. On the religious right, science is sometimes positioned as an antagonist to Christianity or Islam, and is often characterized as a religion itself, especially evolutionary theory. To quote the Institute of Creation Research (I know, I spend too much time looking at sites like this): “Evolutionism is thus intrinsically an atheistic religion.”
I think much of the misunderstanding about science has to do with a focus on conclusions rather than process. This is partly a function of the way science and scientific ideas are reported in popular media. When some finding — margarine is better for one’s heart than butter — is accepted as dogma only to be discredited later, it appears that the scientific method has failed. But the fact that science can accommodate new information and change its conclusions to provide a more accurate description of something is one of its strengths. Science thrives on failure. This is in contrast to many of the belief systems science now finds itself in conflict with, most of which have not changed the explanations they offer (if any) for hundreds or thousands of years.
So, back to that birthday. It’s offers a good excuse to think about a few of the important scientific concepts that have been accepted as mainstream science only during my lifetime. Many replaced earlier theories that had to be discarded or completely revised.
An incomplete list:
• By deciphering the structure and mechanism of DNA in 1953, Watson and Crick explained the mechanism of heredity and showed that life is digital, not analog.
• In 1964, Wilson and Penzias discovered the cosmic background radiation, which allowed other scientists to confirm the Big Bang as the universe’s origin and relegate the steady-state theory to the dustbin of cosmology.
• Continental drift. What is obvious to a second grader — the continents fit together like a jigsaw puzzle and must have been connected at some point — was proposed by a few geologists but resisted by most until the 1960s, when symmetrical magnetic anomalies on the seafloor showed that the continents were separating along the mid-Atlantic Ridge. Continental drift explained not only the shape and position of the continents but the existence of many geological features, such as the Himalaya mountains and the Marianas Trench.
• Until the 1970s, it was widely accepted that all multi-cellular life on earth is dependent on the sun, either directly or indirectly. In 1977, hydrothermal vents were discovered in the Pacific Ocean. These “black smokers” are surrounded by ecosystems that get their energy not from the sun but from dissolved chemicals in hot water emerging from the vents.
• In 1980, Walter and Luis Alvarez discovered a worldwide layer of the element Iridium in strata dating from the end of the dinosaur era 65 million years ago. They proposed a large asteroid impact as a key event in the extinction of the dinosaurs (and many other forms of life), an idea that is widely accepted by earth scientists.
• A few scientists proposed the idea of human-caused global warming as long ago as the 19th century, but it wasn’t until the 1980s that an overwhelming majority of climate scientists accepted the idea of androgenic global warming. As in the case of evolutionary theory, political and cultural factors have resulted in large segments of the population in this country dismissing what is an almost unanimous consensus among scientists.
• In 1998, cosmologists determined that the expansion of the universe is accelerating, probably due to dark energy, something we still don’t understand but which apparently constitutes almost 70% of the mass-energy of the universe.
These are just a few of the new ideas that science, by its own rules, has had to accept over the past 50 or 60 years. I say “had to” because each new idea displaced existing theories that, in many cases, represented the life’s work of other scientists.
But what, one might reasonably ask, does all this have to do with writing non-fiction books for children? It’s a reminder that science is a dynamic, messy affair. It rarely deals in absolutes. Its crowning achievements often turn out to be incorrect or incomplete. Keeping this in mind as we write can help us give young readers a more accurate picture of what science is and how it works.