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Re: Fossil Hunters Told to" Dig Deeper"

Yet another article on dinosaur diversity from the Sydney Morning Herald:

(If anyone wants pdfs of the paper, email me or download a copy from Steve Wang's website at: http://www.swarthmore.edu/NatSci/swang1/Publications/ - Patti)

Dinosaurs in abundance, no bones about it
September 6, 2006

Good news for dinosaur fans: there are probably a lot more waiting to be discovered. At least, their fossils are.
Peter Dodson, of the University of Pennsylvania, and Steve Wang, of Swarthmore College, also in Pennsylvania, estimate that 71 per cent of all Dinosaur genera - groups of dinosaur species - have yet to be unearthed.
"It's a safe bet that a child born today could expect a very fruitful career in dinosaur paleontology," Professor Dodson said.
The estimate appears in the latest issue of Proceedings of the National Academy of Sciences.
Professor Dodson first estimated the potential number of dinosaur genera in 1990 and now is revising that upward.
The estimates are based on the rates of discovery - about 10 to 20 a year - and the recent increase in finds of fossils in China, Mongolia and South Americae.
Professor Dodson suggests 1850 genera will eventually be discovered. So far 527 have been found.
Fossilisation is rare, he and Professor Wang note, and up to half the dinosaur genera that ever existed may have left no fossilised remains.
Associated Press

----- Original Message ----- From: "Patti Kane-Vanni" <pkv1@erols.com>
To: <vrtpaleo@usc.edu>
Sent: Tuesday, September 05, 2006 10:21 AM
Subject: Re: Fossil Hunters Told to" Dig Deeper"

And as a follow-up, the Penn press release in TerraDaily:
Good Times Ahead For Dinosaur Hunters
by Staff Writers
Philadelphia PA (SPX) Sep 05, 2006
The golden age of dinosaur discovery is yet upon us, according to Peter Dodson at the University of Pennsylvania. In a forthcoming issue of the Proceedings of the National Academy of Sciences, Dodson revises his groundbreaking 1990 census on the diversity of discoverable dinosaurs upward by 50%, offering a brighter outlook about the number of dinosaurs waiting to be found.
His findings also add evidence that dinosaur populations were stable, and not on the decline, in the time shortly before their extinction 65 million years ago.
Dodson proposes that 1,850 genera (the plural of genus, an organizational group comprised of one or more separate species) will eventually be discovered, in total. Since the dinosaur research began in earnest in the 19th century, only 527 genera have so far been found, although that number is currently changing at the rate of 10 to 20 per year.
"It's a safe bet that a child born today could expect a very fruitful career in dinosaur paleontology," said Dodson, professor of anatomy in Penn's School of Veterinary Medicine and professor in Penn's Department of Earth and Environmental Sciences. "Unfortunately, there is a finite limit to what can be discovered, so our estimates show that the child's grandchildren won't be so fortunate as new discoveries will likely decline sharply in the early 22nd century."
Dodson and co-author Steve Wang, a statistician at Swarthmore College, estimate that 71% of all dinosaur genera that could be found are still awaiting discovery. The researchers predict that 75% of discoverable genera will be found within 60-100 years and 90% within the next 140 years.
In 1990, Dodson first census paper coincided with his publication of The Dinosauria," the first book to comprehensively depict known dinosaurs. In preparing for the second edition, published last year, Dodson revisited his projections to account for the sudden increase of dinosaur fossil discoveries during the 1990s.
"The 1990s saw an 85% increase in the number of new fossil discoveries," Dodson said. "The dinosaur field used to be the pursuit of white Anglo-Saxons, but, with recent explosion in of dinosaur paleontology in places like China, Mongolia and South America, that is clearly no longer the case. "
Historically, Dodson contends, dinosaur discovery was largely in the hands of British, Canadian and American researchers, with few exceptions in other countries. In recent decades, however, the discovery of new fossil beds, especially in China and Mongolia, has resulted in a greater diversity among dinosaur researchers.
Ultimately, however, there are only so many dinosaurs that can be found. Fossilization itself is a rare event, and there are very few places on Earth, as a whole, where the rocks are of the right age to contain fossils dating back to the dinosaur era. At some point, paleontologists will find all the fossils that could possibly be found.
Dodson and Wang's analysis also offers evidence that dinosaur populations were stable before the extinction event that ended their reign of global dominance. Dodson, however, warns that the picture of the fossil record at the time of extinction is not resolved enough to say definitively.
"We have enough information to say for certain that, within six million years of the meteorite's arrival, dinosaur populations were stable," Dodson said. "But we don't know for certain if there was a decline within that six-million-year slice of time before the extinction event."
Their estimates for total dinosaur diversity take into account the number of dinosaurs already found, the rate of discovery and potential richness of the fossil locations that can be reasonably explored.
They hold that it is still an open question as to whether their estimates of discoverable genera mirror the actual diversity of dinosaur genera that walked the earth. Their findings, combined with previous studies suggest that nearly half of all dinosaur genera that existed did not leave behind fossils that could be found.
"I would never suggest that this prediction, however statistically sound, is the final word on dinosaur diversity," Dodson said. "My intention is to fuel the discussion using the facts at hand, and this is the best estimate we can make with the data available."

----- Original Message ----- From: "Patti Kane-Vanni" <pkv1@erols.com>
To: "SVP Listserve" <vrtpaleo@usc.edu>; "Dinosaur Mailing List" <dinosaur@usc.edu>
Sent: Tuesday, September 05, 2006 6:53 AM
Subject: Fossil Hunters Told to" Dig Deeper"

Peter Dodson & Steve Wang's latest dino fossil count as interpreted by the press:

Fossil hunters told: Dig deeper
"Lots" more dinosaurs await discovery, experts say.

By Tom Avril
Inquirer Staff Writer

Dinosaur hunters of the world, grab your picks and hammers!
You've barely scratched the surface, according to a study published yesterday by scientists at the University of Pennsylvania and Swarthmore College.
A sophisticated statistical analysis suggests paleontologists have unearthed fewer than one-third of the various kinds of dinosaurs to be found, the team wrote in the online edition of Proceedings of the National Academy of Sciences.
"Good news for paleontology," said Steve Wang, an assistant professor of statistics at Swarthmore, who wrote the paper with Penn paleontologist Peter Dodson. "There's still lots out there to find."
A handful of such predictions have been made in the past. But since Dodson last did so in 1990, the rate of dinosaur finds has soared - the result of exploration in new areas and by new people. Once largely the province of white males from the United States, Britain and Canada, the field now encompasses many paleontologists from fossil hotbeds such as China and Argentina.
"It's no longer an imperialistic exercise," Dodson said.
And with the revelation that dinosaurs are ancestors of today's birds, paleontologists have vigorously pursued the smaller creatures that evoke their modern avian cousins.
"The emphasis has shifted from large dinosaurs that are going to add to the 'wow' factor of dinosaurs when mounted in museums," said Luis Chiappe, paleontologist at the Natural History Museum of Los Angeles County.
From the early 1800s until 1990, science had identified 285 dinosaur genera.
(That's the plural of genus - a broader unit of classification than species, as in the "homo" in Homo sapiens.)
Then, in just the last quarter-century, the number climbed to 527, a jump of 85 percent. The total number of "recoverable" genera is 1,844, Dodson and Wang estimated. That doesn't count the likely hundreds of varieties that were not preserved in rock.
Michael Foote, a professor in the department of geophysical sciences at the University of Chicago, said the authors took a sound approach to the problem.
"I really like this paper," said Foote, who was not involved with the work. "I think this is, mathematically, a very rigorous attempt to deal with it."
Wang and Dodson used a statistical technique called an abundance-based coverage estimator - an analysis that took into account how many fossil finds throughout history represented new genera.
Loosely speaking, Wang said, that translates as follows:
"If you're always finding new things, you probably haven't found them all... . If you keep finding the same things over and over and over, that gives you an indication that you've probably found most things out there."
His calculations showed the reality to be somewhere in between.
He and Dodson projected that nearly 400 new varieties would be found in the next 30 years. The pace will likely level off during the 22d century, they wrote.
The authors also tackled a question related to dinosaur extinction. Fossils found to date suggest that dinosaur diversity was already in gradual decline 10 million years before the creatures' ultimate extinction, some experts say.
But Dodson and Wang's statistical method suggests that the population was stable, and that we simply haven't found their fossils yet.
That finding is consistent with the prevailing view that the creatures became extinct during a short period of time, as the result of a meteor impact at the end of the Cretaceous period.
Chiappe, who was not involved with the research, warned that such analysis must be viewed with some caution. If anything, he said, the new estimates might be too low.
Some parts of the world are relatively untapped when it comes to dinosaur fossils, notably Africa because of the turmoil in some countries, Chiappe said. But even traditional hunting grounds still have much to yield, he predicted.
Chiappe himself was part of a team that reported a new small dinosaur earlier this year, a 30-inch meat-eater from Germany dubbed Juravenator starki.
And if the new predictions hold true, there's plenty more to come.
"It's a safe bet," Dodson said, "that a child born today could expect a very fruitful career in dinosaur paleontology."

Contact staff writer Tom Avril at 215-854-2430 or tavril@phillynews.com

Patricia Kane-Vanni
pkv1@erols.com or paleopatti@hotmail.com

"Keep away from people who try to belittle your ambitions. Small people always do that, but really great ones make you feel that you too, can become great." - Mark Twain