Geology: Pace quickening on knowledge of dinosaurs
People’s fascination with dinosaurs continues to grow. That is fueled, at least in part, by periodic releases of Jurassic Park films, but also by exciting new discoveries.
When I started studying dinosaurs professionally about 45 years ago, we were happy to get a few new species each year. For the last decade, we have averaged about 48 a year – that is a new dinosaur every eight days.
New species are still being found in the great American West, even though it has been searched for 150 years, but now explorations in places like Alaska, Antarctica, China, South America and Africa have greatly added to the number and variety of dinosaurs known.
In addition to new species, we also have new ways to study them. CT scans are allowing us to look inside their skulls to map the blood vessels they used to cool their brains, determine how fine their sense of smell might have been, and how acute their vison and hearing was.
Ever more precise measurement of the chemical signatures left in their fossilized bones is allowing us to determine their food preferences, body temperatures, and metabolic rates. We even know the colors of the eggs laid by a few species.
We also now know what colors some dinosaurs were, something that would have been unthinkable just a couple decades ago. Microscopic bodies called melanosomes imbedded in skin and feathers have different shapes, and those shapes produce different colors.
And it is not just the lives of dinosaurs we have learned more about. We also know more about how they died. Recent research showed that the 6-mile-wide meteorite that caused their extinction hit the Yucatan Peninsula when the northern hemisphere was in springtime.
A nice look at recent advances appeared recently when National Geographic came out with a special issue on dinosaurs. My wonderful wife picked one up for me when she saw it at our local Kroger about three weeks ago.
Some of the writing is really good, such as this, when talking about the European Synchrotron Radiation Facility in Grenoble, France, which produces some of the world’s most-powerful X-rays:
Fossils were "scanned finely enough to resolve details as narrow as a human red blood cell. When conditions are just right, Tafforeau's scans can show features less than a hundredth of that width. Such is the power of a magnifying glass the size of a football stadium."
They must be very careful, as "Most of the beams we are using to scan fossils would kill you in just a few seconds."
Of course the book has a large focus on Spinosaurus and its modern-day rediscoverer, Nizar Ibrahim, since National Geographic bankrolled his fieldwork. His discoveries are certainly important, but to say that his work "challenged decades of dogma" is going a bit far. Elsewhere in the book it says we now know of about 1,100 species. To have found one aquatic dinosaur among 1,100 is hardly challenging dogma.
Dale Gnidovec is curator of the Orton Geological Museum at Ohio State University.
gnidovec.1@osu.edu
This article originally appeared on The Columbus Dispatch: Knowledge about dinosaurs growing exponentially
