Ancient meat-eating dinosaurs held their arms with palms facing inwards like their bird descendants, a rare set of 198-million-year-old fossilised handprints has revealed. An analysis of the prints, published this week in PLoS One, supports theories that even very early therapods [lit. ‘beast feet’] such as tyrannosaurs and velociraptors had bird-like forelimbs, and walked only on two legs, well before they evolved feathery wings.
The handprints came from a dinosaur that sat down on the edge of a lake in St George, Utah, and extended its arms far enough to leave sediment marks. Six other resting dinosaur traces have been reported before, but they all lack clear hand prints.
This means, reports the Chicago Tribune, that we must banish images of tyrannosaurs holding their forearms like monkeys, with palms facing downwards – a posture that palaeontologists apparently term the “bunny position” – as depicted in Jurassic Park. Instead, we must imagine that dinosaurs were extremely good at holding basketballs.
“What this seems to imply is that, even from fairly early in their history, dinosaurs were entirely bipedal and weren’t using their forearms to support themselves in any way,” paleontologist Tom Holtz of the University of Maryland, says. “Because of that, the hands could specialize as weapons, to grab on to a struggling animal or to fight with other dinosaurs.”
Image: Dilophosaurus wetherilli in bird-like resting pose/Heather Kyoht Luterman
Los Angeles Times – 3-mar-2009
At left, dinosaur tracks with hand prints show bird-like inward-facing palms at Johnson Farm, Utah. At right, an artist’s reconstruction shows the formation …
National Geographic —————————————————————————–
free access article on PlosOne
Bird-Like Anatomy, Posture, and Behavior Revealed by an Early Jurassic Theropod Dinosaur Resting Trace
Alcuni ricercatori cinesi hanno riconosciuto nelle piume apparteneti ad un Beipaosaurus (Dinosauria, Theropoda, Therizinosauridae) un morfotipo attualmente associato a piume utilizzate per “esibizionismo” (display) e non per il volo. Questa é la prima volta che viene riscontrata questa peculiarità in Teropodi non aviani.
Earliest Feathers for Show, Not Flight
Jennifer Viegas, Discovery News
Jan. 12, 2009 — The world’s first feathers probably had nothing to do with flight or staying warm but were instead for showy display purposes, according to a new study that documents the most primitive known version of feathers, which were found on a Chinese dinosaur.
The dinosaur, Beipiaosaurus, sported the likely colorful feathers on its limbs, trunk, tail, head and neck, with the neck feathers resembling a lion’s mane.
Paleontologists now believe feathers evolved very early in archosaurs, the group that included dinosaurs, pterosaurs and relatives of crocodiles, in addition to today’s modern birds, crocodiles and alligators.
“Our analysis suggests that feathers might have a much longer history than previously thought,” lead author Xing Xu told Discovery News.
“The first feathers might have appeared in the fossil record in the Middle Triassic about 235 million years ago,” said Xu, a paleontologist at the Chinese Academy of Sciences in Beijing.
Xu and colleagues Xiaoting Zheng and Hailu You studied the remains of the Chinese dinosaur, which was excavated at the Early Cretaceous Yixian Formation of Jianchang, western Liaoning. They noticed two types of feathers on the specimen: short, thread-like structures, and longer, stiff, broader ones that represent the rudimentary feathers, according to the study.
Both types are described in a paper published in this week’s Proceedings of the National Academy of Sciences.
Similar structures have been found on Psittacosaurus, or “Parrot Lizard,” as well as some pterosaurs. The researchers therefore suspect the common ancestor of these creatures — along with Beipiaosaurus, which lived 125 million years ago — had the early feathers too.
Previously documented feathers on dinosaurs were described as having multiple filaments, or many fluff-creating strands. The feathers on the recently documented Chinese dinosaur, however, are believed to represent a much more primitive stage, since the feathers consist of just a single broad filament, but have a different structure than hair.
The morphology and distribution of these early feathers rule out use for flight and helping to keep the dinosaur warm, but instead suggest they were flashed during displays, perhaps for mating, identification and competition purposes.
“Most previous studies suggest that insulation might have been the primary function for the first feathers, but our discovery supports that display represents one of the earliest functions for feathers,” Xu said, adding that “flight function appears very late in feather evolution.”
The discovery negates the prior theory that feathers and flight co-evolved. It instead indicates pterosaurs, birds and other fliers recruited already existing feathers for flight.
Xu and her colleagues aren’t certain how feathers came into being in the first place, but they suspect that at some point, an animal’s skin developed epidermal tissue that gave rise to the thin, tubular protrusions. Members of the opposite sex must have liked what they saw in displays, since the trait stuck and flourished. An average bird today has over 20,000 feathers.
Cheng-Ming Chuong and his team from the Keck School of Medicine at the University of Southern California foreshadowed the recent discovery. Their studies on chickens predicted what these first, more basic, feathers would’ve looked like.
“Just like Rome, feathers are not made in one process,” Chuong said, hinting that a long and colorful history for feathers would likely emerge as more findings, such as the new discovery on Beipiaosaurus, come to light.
He added, “While Darwin’s theory has explained the ‘why’ of evolution, much of the ‘how’ remains to be learned. Evo-Devo (evolution of development) research promises a new level of understanding.”
The remains of the flashy, primitive-feathered Chinese dinosaur are now housed at the Shandong Tianyu Museum of Nature in China.
source: Dicovery channel news
IN GERMAN: faz.net
A new feather type in a nonavian theropod and the early evolution of feathers (PNAS link)
Xing Xu, Xiaoting Zheng and Hailu You
All described feathers in nonavian theropods are composite structures formed by multiple filaments. They closely resemble relatively advanced stages predicted by developmental models of the origin of feathers, but not the earliest stage. Here, we report a feather type in two specimens of the basal therizinosaur Beipiaosaurus, in which each individual feather is represented by a single broad filament. This morphotype is congruent with the stage I morphology predicted by developmental models, and all major predicted morphotypes have now been documented in the fossil record. This congruence between the full range of paleontological and developmental data strongly supports the hypothesis that feathers evolved and initially diversified in nonavian theropods before the origin of birds and the evolution of flight.
Pubblicato importante studio sulle capacità olfattive dei dinosauri.
Gli autori dello studio sono partiti dalla tomografia di 21 teschi di Teropodi per ottenere un loro “tasso olfattivo” (‘olfactory ratio’) comparando i diametri del bulbo olfattivo con quello del cervello e tarando il valore ottenuto in funzione della rispettiva massa corporea degli esemplari.
Le considerazioni più importanti possono essere considerate le seguenti:
- Tyrannosaurus rex e Velociraptor, presentano i valori più elevati
- Oviraptoridi (Citipati osmolskae) elo Struthiomimidae Ornithomimus edmontonensis (tutti privi di denti e dotati di becco), avevano il senso dell’olfatto meno sviluppato ed è quindi probabile che fossero più tendenti all’onnivoria che alla carnivoria.
Archaeopteryx, aveva un senso dell’olfatto nella media dei 21 teropodi studiati e simile a quello dei Teropodi più piccoli: ciò è significativo perchè indica che i moderni uccelli hanno perso molto del loro senso dell’olfatto durante l’evoluzione.
Darla Zelenitsky and Tyrannosaurus Rex skull - Stuart Gradon, Calgary Herald
Ornithomimid skull CT scan - Kobayashi, Y - Nature.com
How does your dinosaur smell?
Quite well, on the whole.
An extensive survey of dinosaur skulls adds to the evidence that Tyrannosaurus rex had a killer sense of smell, and finds that the earliest known birds were much better at sniffing out prey than their descendents.
Using fossil evidence to figure out how extinct animals looked and moved is difficult enough — assessing their senses is harder still, and questions about dinosaurs’ sense of smell have been particularly difficult to answer. Comparisons between extinct and modern counterparts that fill similar ecological niches can yield some information, but to really know what an extinct animal could smell, palaeontologists need to look at the creature’s olfactory bulb — the area of the brain dedicated to scent.
Although computed tomography (CT) X-ray scans of T. rex skulls, for example, have previously revealed substantial olfactory bulbs, the scientists behind this latest survey say that it is the first time that trends in smelling ability have been evaluated across a range of meat-eating dinosaurs.
Darla Zelenitsky at the University of Calgary in Alberta, Canada, François Therrie, curator of dinosaur palaeoecology at the Royal Tyrrell Museum in Drumheller, Alberta, and Yoshitsugu Kobayashi of Hokkaido University in Japan, assessed the size and shape of the olfactory bulb in 21 species of theropod — bipedal dinosaurs that were the ancestors of today’s birds.
They took CT scans, along with casts and measurements of brain cases, to calculate an ‘olfactory ratio’ that compares the diameter of the olfactory bulb with the diameter of the brain itself. When adjusted for the body mass of the animal, this ratio gauges the creature’s sense of smell.
The team reports in the Proceedings of the Royal Society B1 that the theropods had a wide range of smelling abilities. Although direct comparisons with modern species are tricky at best, the findings suggest that Velociraptor and T. rex rivalled bloodhounds in their ability to smell prey, says Zelenitsky.
But that won’t settle arguments about whether T. rex was a predator or a scavenger. “While this makes it clear that that these species had a better sense of smell than other theropods of the time, it does not support any arguments that Tyrannosaurus was a scavenger, as there are both predatory and scavenging birds today with large olfactory bulbs,” says Zelenitsky.
The relatively small olfactory bulbs found in other theropods, such as oviraptorids (Citipati osmolskae) and the ostrich-like Ornithomimus edmontonensis — both toothless, beaked dinosaurs — supports theories that the two species were not particularly carnivorous and that plants may have comprised a big part of their diet.
Remarkably, Archaeopteryx, the earliest known flying bird, had a sense of smell that was quite average among the 21 theropods. “This was surprising because modern birds are thought, with few exceptions, to have poor senses of smell, yet clearly Archaeopteryx had an olfactory-bulb size typical of that of a small theropod dinosaur,” comments Zelenitsky. This suggests that birds may have lost much of their sense of smell later in their evolution.
“This is a major step towards understanding dinosaur sensory function,” says anatomist Lawrence Witmer at Ohio University in Athens. “With more work like this we should be able to have a very good idea of how these animals, saw, smelled, and felt the world around them.” However, he points out that there are limits to how much CT scanning technique can reveal: “We shouldn’t try to paint with too fine a brush — this is neurology without the neurons.”
As a next step, “it would be fascinating to compare these data to similar measurements collected from a range of animals, especially lizards and ground-dwelling birds like the kiwi, which is both nocturnal and known to have an excellent sense of smell,” says palaeontologist Philip Currie at the University of Alberta.
“Seeing all of these data in one place is pretty cool,” he adds. “I can’t wait to go through all of it with a fine-toothed comb and see if it confirms our thinking on who is related to who, and which lineages led to birds.”
- Proc. R. Soc. B doi:10.1098/rspb.2008.1075 (2008).
Dinosaur Smelling Skills Open New Angle On Bird Evolution
Science Daily (press release) – 8 ore fa
ScienceDaily (Oct. 28, 2008) – Although we know quite a bit about the lifestyle of dinosaur; where they lived, what they ate, how they walked, not much was known about their sense of smell, until now.
Tyrannosaurus rex noses out dinosaur competition Reuters
T. rex had nose for finding dinner Calgary Herald
The Press Association – AOL Canada – LiveScience.com – Canoe.ca
e altri 34 articoli simili »
links will be posted when available online
In Thailandia un contadino scopre nuovo sito con resti fossili di dinosauri (sauropodi e teropodi) datato 150 milioni di anni fa.
Second big fossil site unearthed at Kalasin
A new site rich in dinosaur fossils has been found in Kalasin province, with some of the fossils estimated to be 150 million years old. The new site is the second fossil discovery in the area after the find at Phu Kum Khao.
The new discovery was made in tambon Din Chee in Kham Muang district near the Phu Phan mountain range.
The fossils were found on land owned by Seethan Saengsit, 62, who made the discovery while working on her land.
Thida Saneyamoon, the chief of the geological survey unit of the Mineral Resources Department, said an initial dig had turned up several types of dinosaur fossils – sauropods and theropods – which were estimated to have roamed the area at least 150 million years ago.
There are also a number of fossils of crocodiles and fish, also estimated to be 150 million years old.
The fossils are to undergo a thorough examination by officials from the department. Ms Thida said the newly discovered fossils would be kept at the Sirindhorn Museum in Sahatsakhan district in Kalasin, where a number of rare fossils of crocodiles and replica skeletons of dinosaurs found in the region have been put on display.
Decha Tantiyawarong, the governor of Kalasin, said he had been told by the Mineral Resources Department that more than 100 fossils had been found.
The discovery was the second in the province following the find at Phu Kum Khao, which has some of the largest fossil deposits in Southeast Asia.
The governor said he had ordered the area to be guarded around the clock to prevent people digging up more fossils to supply illegal fossil traders.
The province bans the removal of fossils from the area without permission.
Based on the new Paleontological Research Protection Act of 2008, effective in August, anyone caught exporting rare fossils without permission could be jailed for up to seven years, or face a fine of up to 700,000 baht, and those trading in fossils without a licence face a one-year prison term or a 100,000 baht fine.
Any fossil discoveries have to be reported to the authorities within seven days, and those wanting to trade in fossils need to obtain a licence.
Anyone in possession of fossils needs to inform the Mineral Resources Department, either in writing or verbally within one year – by Aug 9, 2009 – or face a fine of up to 10,000 baht.
In Corea del sud è cominciato l’iter che potrebbe portare 5 aree con resti di Dinosauri ad essere inserite nella lista dei luoghi “patrimonio dell’umanita” UNESCO:
Haenam: il primo luogo al mondo dove sono tate trovate insieme impronte di Pterosauri e Uccelli (e di numerosi artropodi).
Hwasun: 1.550 impronte incluse quelle appartenenti a ben 60 teropodi
Su un isola presso Yeosu: 3500 impronte di dinosauri compresa una pista appatenente a un ornitopode lunga 85 metri.
Goseong: maggior concentrazione di impronte al mondo (con un gruppo con imponte di 410 individui) e con abbondanza di impronte di sauropodi (139) e ornitopodi.
Boseong: 200 uova di dinosauro con diametro variabile da 60 a 180 mm e appartenenti a Sauropodi e Ornitopodi’. Presenti pure ossa di dinosauri e ossa e uova di tartarughe.
vedi pure precedente post del 2008-05-16: Impronte di baby Sauropodi in Korea
‘Dinosaur Coast’ Seeks UNESCO Listing
Prof. Huh Min, from Chonnam National University, inset photo, has initiated a campaign to have five areas of the southern coastline with thousands of dinosaur footprints listed on the U.N. Educational, Scientific and Cultural Organization World Natural Heritage list. As seen in the photo, Yeosu, South Jeolla Province, one of the five areas, has an 85-meter-long ornithopod track. / Courtesy of Chonnam National University
By Bae Ji-sook
A campaign has been started to have five areas of the southern coastline where thousands of dinosaur footprints are to be found listed on the U.N. Educational, Scientific and Cultural Organization (UNESCO) World Natural Heritage list.
The five are Haenam, Hwasun, Boseong, and Yeonsu in South Jeolla Province, and Goseong in South Gyeonsang Province.
If successful, the move will follow the 2007 listing of Jeju Island.
Haenam was the first place in the world where dinosaur, pterosaur and bird tracks were found together. It also has numerous large arthropod tracks. The 7.3-meter long tracks made by a flying reptile are visible at the center of the fossil site, which is listed as Natural Treasure No. 394.
In Hwasun, there are about 1,500 footprints, including those belonging to more than 60 theropods.
On an island off Yeosu are a total of 3,500 dinosaur footprints, including an 85-meter-long track made by an ornithopod. The large number of footprints is thought to show that the southwestern area was primarily covered with mesic forests.
Boseong has 200 fossilized eggs, ranging from 60 millimeters (mm) to 180 mms in diameter, from sauropods and ornithpods. Well-preserved dinosaur bones, and turtle bones and eggs are also at the site.
Goseong has the highest concentration of tracks in the world, including the footprints of 410 individuals in one group. It also has the most abundant ornithopod footprints as well as 139 sauropod footprints.
UNESCO is to start a field study there from Saturday.
Prof. Huh Min, from Chonnam National University and director of the Korea Dinosaur Research Center, is initiating the campaign. He stressed that having a natural heritage is somewhat different from having a cultural site. Korea has eight cultural sites, including old palaces.
“Unlike cultural sites featuring their comparative value to different cultures, the natural sites have to be the `only one’ valuable to the world. It has to be academically, culturally, and in every way the best in the world,” he said.
To receive the UNESCO Natural Heritage listing, support from local residents and the administrations is critical. The preparation committee has established safe and protective pathways for visitors as well as straightened roads to preclude any possible destruction of the sites. “We have streamlined the region,” Huh said.
Preparation has been underway for more than three years, and he expects UNESCO inspectors to recognize the value and importance of the “Korean Cretaceous Dinosaur Coast.”
“We have seen dinosaurs in Western movies such as Jurassic Park and picture books. But here, we also had flying reptiles, and all kinds of dinosaurs walking, drinking, laying eggs and living just like any other creature,” he said.
Huh was selected as one of the 100 top scientists in the world by the International Biographical Center of Cambridge, England, in 2005; one of the 2,000 Outstanding Scientists of the 21st Century by the same institution in 2003; and one of the Great Minds of the 21st Century by the American Biographical Institute; for his pioneering studies on dinosaurs.
see also previous post: 2008-05-16: Impronte di baby Sauropodi in Korea
Nel nuovo cimitero dei dinosauri nello Utah meridionale, studiato da Luis Chiappe, sorprendentemente vi sono impronte e resti fossili sia del Giurassico che del Cretaceo.
Tra i primi, datati intorno a 145 milioni di anni fa, vanno annoverati un nuovo sauropode chiamato informalmente “Gnatalie”, e impronte di Stegosauro finora rinvenute solo in Europa (Deltapodus).
Tra i resti del Cretaceo vi sono invece impronte di Sauropodi, Teropodi e Ornitopodi.
‘Dinosaur graveyard’ found in southeast Utah
A 150-million-year-old sauropod skeleton is the centerpiece of the finds from the Jurassic and Cretaceous periods, discovered by a Los Angeles team.
Los Angeles researchers have discovered a “dinosaur graveyard” in southeastern Utah that is yielding a wealth of fossilized animals and footprints from the Jurassic and Cretaceous periods.
The centerpiece of the new finds is the well-preserved skeleton of a 150-million-year-old sauropod — a long-necked herbivore — that researchers have named “Gnatalie” because the scientists were “eaten alive” by gnats while they were excavating it earlier this year.
The team has so far excavated only part of the fossilized skeleton, which they estimate to be about 50 feet long. “It’s big and takes a lot of time,” said paleontologist Luis Chiappe, director of the Dinosaur Institute and the Natural History Museum of Los Angeles County.
Gnatalie was found in the remains of what was once a big riverbed and is now a light-colored stratum on the face of an exposed cliff. Nearby in the bed were the disarticulated remains of other sauropods and meat-eating dinosaurs, including the five-foot-long femur of a brachiosaur.
On the ridgeline of the cliff, the team found a large number of footprints preserved in sandstone. Surprisingly, one set of prints from the Jurassic era, which ended about 145 million years ago, prints of a sauropod were found near tracks of carnivorous theropods and herbivorous ornithopods from the early Cretaceous period, which ended about 65 million years ago.
Most stunning of all, to Chiappe, were the three-toed prints of a European stegosaur, named “Deltapodus tracks have never been found in North America,” he said.
Chiappe and his staff, led by Doug Goudreau and Aisling Farrell, expect to spend at least another decade excavating the site.
The finds will be the centerpiece of an exhibit at the Natural History Museum of Los Angeles County that will open in 2011, he said.
A renovation of the dinosaur exhibit is part of the museum’s $84-million project to restore and seismically strengthen its original 1913 Beaux-Arts-inspired building.
other links (updated on 2008-10-18 11:48 Italy):
|‘Dinosaur graveyard’ found in southeast Utah
Los Angeles Times – 44 minuti fa
A 150-million-year-old sauropod skeleton is the centerpiece of the finds from the Jurassic and Cretaceous periods, discovered by a Los Angeles team. …
|No visas required for six countries
Boston Globe – 3 ore fa
President Bush, trying to eliminate a major source of contention with allied nations, announced yesterday that the United States is rescinding visa …
|UPI NewsTrack Health and Science News
United Press International – 6 ore fa
LOS ANGELES, Oct. 17 (UPI) — Researchers said a dinosaur graveyard discovered in Utah holds a wealth of fossils from the Jurassic and Cretaceous periods. …
|Sauropod found in dinosaur graveyard
United Press International – 8 ore fa
LOS ANGELES, Oct. 17 (UPI) — Researchers said a dinosaur graveyard discovered in Utah holds a wealth of fossils from the Jurassic and Cretaceous periods. …
|Willow Plants Cleaning Up Contamination
istockAnalyst.com (press release) – 6 ore fa
(Source: United Press International)Researchers said 23000 willow plants are helping clean up a 164000-gallon underground fuel leak at a US Army base. …
Scoperto dinosauro carnivoro che respirava come uccelli odierni
martedì, 30 settembre 2008 8.50
CHICAGO (Reuters) – Alcuni scienziati hanno rinvenuto i resti di un dinosauro carnivoro di grossa taglia con un apparato respiratorio molto simile a quello di un uccello di oggi. La scoperta rafforza l’idea che ci sia un legame tra volatili e dinosauri e contribuisce a spiegare l’evoluzione del sistema respiratorio proprio solo degli uccelli.
Estratto da rocce datate 85 milioni di anni, lungo le rive del Rio Colorado nella provincia argentina di Mendoza, questo predatore lungo 10 metri e che camminava in posizione eretta pesava quanto un elefante e aveva probabilmente le piume, secondo quanto hanno riferito gli scienziati.
Ma il suo apparato respiratorio rende questo dinosauro unico, ha detto Paul Sereno dell’Università di Chicago, che ha scritto della scoperta sulla rivista Plos One.
Al posto dei polmoni che si espandono e restringono, ha detto Sereno, questo animale potrebbe aver avuto delle sacche d’aria che funzionavano come una sorta di soffietto, che spingevano l’aria nei polmoni rigidi, come accade negli uccelli.
Il team di studiosi ha nominato il dinosauro Aerosteon riocoloradensis (“ossa areate del Rio Colorado”), perché le sue ossa hanno una conformazione a spugna nota come “pneumatizzazione”.
Gran parte dei paleontologi pensa che gli uccelli si siano evoluti da piccoli dinosauri carnivori con le piume, e il primo uccello rinvenuto è molto simile a uno di questi animali estinti.
vedi commenti e approfondimenti dal post: link (dai blog “Theropoda” e SVPOW)
Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina
Living birds possess a unique heterogeneous pulmonary system composed of a rigid, dorsally-anchored lung and several compliant air sacs that operate as bellows, driving inspired air through the lung. Evidence from the fossil record for the origin and evolution of this system is extremely limited, because lungs do not fossilize and because the bellow-like air sacs in living birds only rarely penetrate (pneumatize) skeletal bone and thus leave a record of their presence.
MSU paleontologist part of team that discovered new dinosaur (with photos)
|Bus-Sized Dinosaur Breathed Like Birds Do
FOXNews – 30 set 2008
By Jeanna Bryner This rendering of Aerosteon shows its lungs (red) and air sacs (other colors) as they might have been in life about 85 million years ago. …
|New scary, cool dino was Tweety’s great-grandpa
Chicago Sun-Times – 30 set 2008
BY DAVE NEWBART Staff Reporter email@example.com But Aerosteon — a new dinosaur discovery announced Monday by University of Chicago paleontologist Paul …
|Please Stop, Dad; I’m So Embarrassed
Washington Post – 29 set 2008
A new study shows that adolescents use a different part of their brain than adults to process emotions such as guilt or embarrassment. …
Science News – 29 set 2008
By Laura Sanders Paleontologists have discovered a new species of carnivorous dinosaur that possessed an interesting feature: It breathed like a bird. …
|Birdlike Dinosaur Found in Argentina
National Geographic – 29 set 2008
A new predatory dinosaur with a birdlike breathing system found in Argentina may help scientists better understand the evolution of birds’ lung systems. …
|Dinosaur predator breathed like a modern bird
Reuters – 29 set 2008
By Julie Steenhuysen CHICAGO (Reuters) – Scientists have unearthed the remains of a large meat-eating dinosaur with a breathing apparatus much like a modern …
|Dinosaur’s fowl breath seals tie to birds
ABC Science Online – 29 set 2008
The discovery of air sacs in a new 10-metre-long, meat-eating dinosaur may seal the connection between birds and dinosaurs and explain how birds’ unique …
|Luftschlauch-Dino lässt Forscher rätseln
Spiegel Online – 30 set 2008
Forscher haben einen bizarren Dinosaurier mit einem System von Luftkanälen unter der Haut entdeckt. Das Tier besaß ein dichtes Federkleid und war so schwer …
PEACE REGION PALAEONTOLOGY RESEARCH CENTRE SCIENTISTS DOCUMENT IMPORTANT DINOSAUR TRACK SITE
Elk Valley Coal District, Southeastern British Columbia
Wednesday September 03, 2008
Southeastern British Columbia is well known as a major region for coal production, something that is shared in common with the Peace Region in the northeastern part of the province. What is not as well known is that the Elk Valley Coal District is home to some of the most significant fossil footprint sites in western Canada. This may not come as a surprise to residents of the Peace Region where dinosaur tracks have been found in proximity to coal seams from as far back as the 1920’s, and right up to recent finds in the Trend Mine near Tumbler Ridge. Dinosaur tracks have been known locally in the southeast part of the province for more than two decades and are found as a bi-product of coal-mining.
The Elk Valley coal comes from a package of rocks known as the Mist Mountain Formation and is the oldest record of terrestrial (non-marine) rocks in western Canada. The Mist Mountain Formation rock layers straddle the Jurassic-Cretaceous boundary and were deposited approximately 135 million years ago along the coastal region of an inland sea that stretched from the Arctic Ocean almost to the Gulf of Mexico.
By comparison, much of the coal that is produced in the Tumbler Ridge area is approximately 100 million years old.
It should be noted that the record of dinosaur bones is quite incomplete in western Canada, with the majority of bones found in rocks between 75-65 million years old. Nearly all of these specimens come from Alberta. The first excavation of B.C. dinosaurs from near Tumbler Ridge took that record back substantially to 93-95 million years. By comparison fossil tracks provide a fairly complete record of terrestrial vertebrates (including dinosaurs) in western Canada between 135-55 million years ago (an 80 million year time span). The tracks then fill significant gaps left by an incomplete skeletal record.
In early August a substantial track site find in the Elk Valley Coal District was reported to the PRPRC simultaneously from the University of Alberta and the Royal Tyrrell Museum in Drumheller. The reports included several photographs showing evidence of several series of footprints from very, very large dinosaurs known as sauropods, also referred to informally as ‘brontosaurs’. Upon receiving word of the new track site and viewing the photographs PRPRC palaeontologist Rich McCrea and assistant Tyler Shaw immediately organized a two week research expedition. There was good reason for such a quick response. Until recently, Canada had not a single record sauropod dinosaurs either from footprints or bones. In fact the absence of sauropod dinosaurs in Canada was something of a mystery that palaeontologists were at a loss to explain. Sauropod bones and tracks are well known in the United States with discoveries as far north as Montana and Wyoming. Where then were the Canadian sauropods? One reason cited for their conspicuous absence included possible geographic barriers (mountains, inland seas, etc.) that prevented sauropods from entering regions that are now a part of Canada. Another explanation was that sauropods preferred habitats that simply did not exist in Canada at the time of their existence.
One of the strengths of science is that previously accepted and in-grained concepts and ideas may change, or evolve, in the face of the weight of new evidence. Such was the case with supposed absence of Canadian sauropods when, in the fall of 2005, Rich McCrea presented a paper at an international palaeontology symposium in Mesa, Arizona detailing the discovery of this major group of dinosaurs from … the Elk Valley Coal District of southeastern British Columbia! The evidence that Rich presented was based on isolated footprint blocks found in talus piles below open coal pits from research he had conducted in that area since 2000, well before his involvement with the Tumbler Ridge museum project. Canadian sauropods were now an accepted reality, but trackways of these animals on intact surfaces were lacking.
The significance of the recent track find from the Elk Valley Coal District is that it provided the first evidence of trackways (long series of prints from one or more individuals) of sauropods from Canada. Palaeontologists can get much more information from trackways than from single footprints, such as: a better idea of the size of the track-maker; how fast the track-maker was traveling; the habitats in which the track-maker lived; whether the track-maker was traveling alone or in a herd; what other animals were present; etc.
Upon the research team’s arrival at the coal mine the mine staff gave a safety orientation and then provided a buggy whip and radio for the palaeontologists’ use when driving on mine property. The generous access to the track site as well as the good will and assistance provided to the PRRPC research team by the mine cannot be understated.
The track site itself was exposed near a mountain top in an exploration area in the coal mine at close to 2300 metres elevation on a vertical face 48 metres long by 15 metres tall. The vertical nature of the track wall necessitated the use of several ropes and climbing gear to gain access to the track surface. Once on the wall it was evident to the research team there were at least three sauropod trackways and three trackways of large meat-eating dinosaurs (theropods), as well as one trackway from a small theropod.
The sauropod tracks were nearly one metre in length and were impressed quite deeply in the track surface. The researchers noted with alarm that the track surface was slowly crumbling to pieces and that the tracks likely would succumb to the forces of erosion within the next one or two years. It was imperative to have a permanent record of at least a portion of this track surface before it was destroyed.
An ambitious replication project was begun in which the palaeontologists used nearly 45 gallons ($5,000 value) of liquid latex to create a replica peel of the most prominent sauropod trackway. This latex peel measured almost 10 metres long by 3 metres wide and required many applications of latex layers to build it up. The application of a single layer of latex took nearly an entire day. When the latex peel was completed it was visible from more than 8.5km away! Once back at the PRPRC the latex peel would be used to create high-fidelity casts for permanent research and display in the PRPRC.
The palaeontologists explored other areas in the vicinity of the main track site while waiting for the latex layers to dry. They were lucky enough to notice a small three-toed footprint on another vertical surface that was located close to the ground. This new track surface was overlain by other thick rock layers, but after several hours of careful work the scientists were able to expose a short trackway of a small theropod (meat-eating dinosaur) with six footprints preserved. This trackway was on a fractured surface near an area of future mining activity.
The palaeontologists decided to attempt to recover the entire trackway for the PRPRC collections. The recovery of the original trackway slab was a painstaking process as the track layer was only a few centimeters thick, but over two metres long, heavy, and potentially unstable. To begin, palaeontologists covered the trackway with a full latex peel. There were two purposes for this. First, if anything went wrong with the removal there would at least be some record of the trackway in its pristine condition as the latex peel could be used to make an exact replica for research and display. Second, the latex peel could hold the track slab together preventing it from falling apart during the removal, and also cushion it for the bumpy 1300km ride to Tumbler Ridge. Once the latex peel was completed it was time to get down to the business of removing the track slab. After several precision cuts with a rocksaw the palaeontologists were able to custom fit a wooden frame over the track slab before undercutting it with chisels to break it away from the rock wall. The track slab was successfully popped off and was carefully flipped over to allow the wooden frame to be completed. The final specimen weighed between 200-250 kilograms.
The final day, August 24th, saw the removal of the large latex peel covering the sauropod trackway which would weigh another 200-250 kilograms. Fortunately the latex peel was able to be rolled up to fit in the truck box with the help of one of the coal mine staff. The palaeontologists took down their ropes and loaded up the rest of their equipment and began the long, careful drive back to Tumbler Ridge, arriving at 1am Tuesday morning after a very successful trip. The specimens were immediately unloaded into the new museum facility (formerly known as Claude Galibois Elementary School) and now are waiting there patiently for some much needed preparation and casting. More work is needed at this track site, including detailed mapping, measuring and photography of the track surface. Since the palaeontologists have been assured of the welcome of their presence in the mine a follow-up trip could be planned for this September, or early in the summer of 2009.
This research trip is one of many planned to various parts of the province to document British Columbia’s diverse palaeontological heritage and recover important palaeontological specimens for research and display. It is the ultimate goal of the Tumbler Ridge Museum Foundation and the Peace Region Palaeontology Research Centre (PRPRC) to become the central repository and display centre for British Columbia vertebrate fossils as well as an international centre of excellence for palaeontological research and education. The Dinosaur Discovery Gallery in Tumbler Ridge is the only museum in Canada that possesses a trackway of Canada’s largest dinosaurs (sauropods). The public will be able to view this unique specimen when the museum reopens at its new location in the early summer of 2009.