Tyrannosaurus rex ... Palaeontologists should expect to unearth a thousand new species of dinosaurs in the next one hundred years.
Credit: David Monniaux/Wikimedia
SYDNEY, 5 September 2006: Palaeontologists should expect to unearth over a thousand new species of dinosaurs in the next one hundred years, according to a report to be published in the U.S. journal Proceedings of the National Academy of Sciences this week.
Authors Steve Wang of Swarthmore College, Pennsylvania, and Peter Dodson from the University of Pennsylvania predict that 75 per cent of all ‘discoverable' dinosaur genera will be found by the year 2102, and up to 90 per cent by 2148.
"We currently estimate dinosaur diversity - including genera that remain to be discovered - at 1,844 genera," they said. "Twenty-nine per cent of all discoverable genera are currently known, whereas 71 per cent remain unknown."
Discovery rates are currently at an unprecedented high, and are set to continue, with an average of 14.8 genera being found and described annually since 1990, compared to 1.1 per year between 1824 and 1969. That's more than a ten-fold increase in discovery rates in less than 30 years.
In China and Argentina, for instance, where palaeontologic activity is burgeoning, discovery rates have increased by 132 per cent and 165 per cent respectively over a 15 year period.
"All together, 242 new genera have been discovered [worldwide] since 1990, an 85 per cent increase,' said Wang and Dodson.
Despite this "remarkable pace of discovery", however, they said little effort has actually been invested, until now, in estimating the diversity of dinosaurs, and that known diversity is biased by the availability or scarcity of fossil-bearing rock.
To arrive at figures of their own, they applied a statistical method, known as the abundance-based coverage estimator (ACE), which took into consideration updated databases, rates of genera discovery and techniques used by palaeontologists, as well as accounting for the incompleteness of fossil records.
Of their estimated 1,844 genera, most should be discovered within 140 years, they predicted.
But of course, some will never be found.
"A genus that left no fossils at all, because of lack of preservation, loss due to subduction ... or other factors, can never be discovered," wrote Wang and Dobson.
Indeed, of the 527 genera currently recognised, 59 per cent are known from only a single individual, and many of these from incomplete material, whereas many other genera, described from nondiagnostic material, such as isolated teeth, have been invalidated.
"These factors have posed substantial challenges to assessing the diversity of dinosaurs," the authors said.
