Ornithopods - Hadrosaur, Ceratopsian

Theropods - Tyrannosaurus, Deinonychus

Sauropods - Malawisaurus, Alamosaurus

Edmontosaurus sp.

Period: Upper Cretaceous, Boquillas formation

Location: near Terlingua Texas

Collection: Ken Barns, cast by the Bonehead Club

Size: a fully grown adult could reach 30 feet long

Click the picture for more photos!

Note: The Edmontosaurus is the most complete Hadrosaurs from Texas, but identification is difficult.  The best distinction is the top of the skull, which has not yet been located.  It might be a Kritosaurus or a Saurolophus.

Hadrosaur egg - cast

Period: Upper Cretaceous, Boquillas formation

Location: (purchased)

Collection: Judie Ostlien

Size: 5" wide flattened ball

Hadrosaurs

As the most successful herbaceous dinosaur, Hadrosaurs lived on every continent, including Antarctica. They had more individuals, more species, and the best fossil record of all the Ornithischian.  Hadrosaurs were the first bipedal herbivore to occupy nearly every size range.  The smallest species is only 3 ½ feet long, the largest over 66 feet.

Mummified specimens of Edmontosaurus (Wyoming) show the skin as thin and leathery.  Round horn-like bumps, called tubercles, patterned their skin, clustering on the throat, neck, and sides.  These bumps were the only protection individuals had from predators.  For defense Hadrosaurs utilized the same technique as modern animals.  Large herds roamed the North American continent like buffalo.  Communal nesting grounds have been discovered where parents safeguarded their hatchlings.

Hadrosaurs had stiff backs and tails where ossified tendons restricted side-to-side movement.  But the stiffness, wide build, and low center of gravity gave the Hadrosaurs an advantage.  They could rotate quickly on their hind legs, outmaneuvering a predator like Tyrannosaurus rex.

Head

Ornithopod’s narrow muzzles allowed them to feed selectively, a first in the Dinosauria.  Though they probably did not have lips, their beak could easily pluck choice conifer needles, leaves, and seeds. Vegetation was ground up using hundreds of cheek teeth.  Cheek pouches kept food from escaping.

Hadrosaurs had the most advanced form of jaws and teeth of all the dinosaurs, possibly superior to present-day herbivorous animals.  Their deep jaws produced hundreds of interlocking, multi-rowed, diamond-shaped teeth with thick strong enamel.  The teeth grew continuously, like a beavers, replacing the working edge as they wore down.  The loosely jointed maxilla (upper jaw) allowed it to “hinge” outward slightly.  This gave a sideways motion.  Their dentary (lower jaw) teeth could slide forward and backward across those of the maxilla. Together the jaws and teeth could chew, a first in the Dinosauria.

All the Hadrosaurs had enlarged nasal chambers. The extent of this enlargement splits Hadrosaurs into two groups, with or without hollow nasal crests.  The animals with smaller chambers, like Edmontosaurus, may have sounded like oboes.  The ones with large crests, like Parasaurolophus, may have sounded like a French horn or trombone.

Another attribute of the Hadrosaurs is that they have the largest brain size to mass ratio of all the ornithischians.  There is no way to tell their IQ level from fossils.  The only animal group with a larger ratio is the Theropods.

Hadrosaurs found in Texas.

Iguanodon: Early Cretaceous, 30 ft long, 10,000 lbs., from West Texas and N. Central Texas.  Largest ornithopod to live in Texas. One of the first dinosaurs collected and classified in England.  At first they thought the teeth belonged to a rhinoceros and the bones to a hippopotamus.  Then they were compared to an iguana’s teeth, thus Iguanodon.  The thumb claw was first thought to be a horn.

Tenontosaurus: Early Cretaceous, 20 ft long, 3000 lbs., from N. Central Texas.  The most common ornithopod in Texas Early Cretaceous.

Hypsilophodontids: may be a small Tenontosaurus, Early Cretaceous, 6 ft long, 85 lbs., from Proctor Lake Texas

Protohadro: Middle Cretaceous, 25 ft long, 4000 lbs., from just north of DFW Texas.  One of the earliest Hadrosaurs anywhere in the world.

Kritosaurus: Late Cretaceous, 30 ft long, 4500 lbs., from the Big Bend of Texas and N. E. Texas.  From the Aguja Formation.  The earliest Hadrosaur of Big Bend.

Edmontosaurus: Late Cretaceous, 35 ft long, 5500 lbs., from the Big Bend of Texas.  From the Aguja Formation,. Most specimens are fragmentary in Texas, so no species name has been given.  Name comes from the first Edmontosaur found in Edmonton, Canada.

Chasmosaurus mariscalensis - skull

(KAZ-moh-SAW-rus MARE-Y-skal-EN-sis)

Period: Upper Cretaceous, Boquillas formation

Location: Big Bend National Park, Texas

Collection: Texas Memorial Museum at Austin

Size: ? mm long

Chasmosaurus mariscalensis - vertebra

(KAZ-moh-SAW-rus MARE-Y-skal-EN-sis)

Period: Upper Cretaceous, Javelina formation

Location: near Terlingua Texas

Collection: Ken Barns, cast by the Bonehead Club

Size: ? mm long

Chasmosaurus mariscalensis - vertebra

(KAZ-moh-SAW-rus MARE-Y-skal-EN-sis)

Period: Upper Cretaceous, Javelina formation

Location: near Terlingua Texas

Collection: Ken Barns, cast by the Bonehead Club

Size: ? mm long

Note:  This vertebra is covered in crocodile tooth marks, probably Deinosuchus rugosus.

Chasmosaurus mariscalensis

This skull represents a moderate sized Ceratopsian, many grew much larger.  Most Ceratopsians lived north of Texas, from Colorado to Alaska, including many species of Chasmosaurs.  Only found in Texas, Chasmosaurus mariscalensis lived the farthest south.  It inhabited the once thriving swamps that are now called the Aguja Formation of Big Bend.

Adults could were 16-25 feet long and 7-9 feet tall with skulls of about 5 feet long.  Chasmosaurus mariscalensis are noted for larger brow horns and shorter nose horns then other species.  This species has the largest fenestra (hole) behind the eye socket of any other Chasmosaur.

Ceratopsians

The Ceratopsians are the horned and frilled Ornithischian dinosaurs.  The first Ceratopsian fossils, a pair of horns, were found in 1887.  O. C. Marsh named the new species Bison alticornis thinking it a large buffalo.  This idea was soon shattered by finding the first complete skull.  He changed the name to Triceratops alticornis.

Originating in Asia near the end of the Cretaceous and migrating to North America, they are one of the last major groups of dinosaurs to evolve.  All are herbaceous herd animals with heavy triangular heads and parrot-like beaks. Unique for dinosaurs, the beak was covered in a horny bill.  Their sizes ranged from a turkey to an elephant. The largest animals have been estimated to weigh more than 3 times a modern rhinoceros.

Ceratopsian horn and frill sizes are thought to be gender-specific. That means that a male and female of the same species could have different size or shaped horns and frills.  This makes identifying individual species difficult.  In the last few years, many specimens have been reclassified as different sex or juvenile members of other species.

Head

The horns and frills of Ceratopsians were probably used in ritualized battles, similar to a modern moose.  Though some species could use their horns as defensive weapons others could not. Only a few skulls with fight damage have been found.  The minimal wounds healed before death. Interestingly, the more ornate the frill, the fewer injuries are recorded. The frill is a very delicate structure, often quite thin.  They can be long, short, wide, or narrow, with or without holes.  Elaborate knobs, spikes and horns adorned the outer edges. The horns come in various sizes and shapes and keratin sheaths covered the them in life.  Keratin is the same material as horse’s hooves and our fingernails.

Ceratopsian nasal openings are extremely large.  This usually means the animal had a good sense of smell.  A few of the larger Ceratopsians also had large frontal sinuses between the base of the horns and the braincase.  In present day antelope and goats, a similar opening acts as a shock absorber, shielding the brain from injury during impact.

Ceratopsians have the largest brains of all the herbivorous dinosaurs.  Still, an alligator of similar size would have a larger one.  The eye sockets and brain structure indicate the Ceratopsians probably had large eyes with good eyesight.  It is guessed they also had color vision like modern reptiles.

Teeth

Ceratopsians’ teeth were very advanced, shearing food instead of crushing, grinding, or ripping.  The jaw acted like self-sharpening scissors. Stacked 5 tall, they grew continuously from the bottom up.  As the tooth wore down, it was replaced by a new cutting surface.

The beak and shearing suggests they ate fibrous foods, like palm fronds or tree trunks.  Ceratopsians could possibly chew their food and had cheeks pouches to catch food particles.

Legs and Feet

Paleontologists still debate the stance of the Ceratopsian’s front legs.  Tracks show the front feet in line with the rear feet.  The animal’s hips are wide and match the tracks.  The front part of the rib cage is narrow widening toward the belly.  This dictates a narrow shoulder.  If the front legs stood erect then the feet would not be in line with the rear.  To have in line stance, the front legs had to be sprawled, unlike any other dinosaur.

Like the Hadrosaurs, Ceratopsians did not have claws.  Keratin covered their unguals (the last digit of each foot) like multiple horse hooves.

Ceratopsians found in Texas

Chasmosaurus means “Chasm lizard” and refers to the very large holes in the frill.  Most, if not all, the long-frilled horned dinosaurs are derived from the Chasmosaurs.  Though not the most famous horned dinosaur, they they do have the broadest geographic range.  Lived 76-70 Ma.

Triceratops (trye-SER-uh-tops), one of the most famous dinosaurs, was the first Ceratopsian found.  Tri means three and refers to the number of horns.  Characterized by huge horns above each eye that could be up to 3 feet long, and broad frills up to 7 feet wide.  They are the only large Ceratopsian without openings in the frill.  Lived 68-65 Ma.

Torosaurus (TOR-uh-SAW-rus) has the second largest skull of any animal ever to live on land it was over 8.5 feet long.  Closely related to the Pentaceratops, these animals very thick and long eye horns resembled those of bulls.  The Spanish word for bull is toro.  Lived 70-65 Ma.

Pentaceratops (PEN-tuh-SER-uh-tops) is the largest of the family.  It had the largest skull of any terrestrial vertebrate, 9 feet. The total length of the skull and frill is longer than its backbone from head to pelvis.  Penta means five and refers to the number of horns.  It had two very long horns behind the eyes and a shorter one on the snout. The two additional horns are actually elongated cheek bones.  Found in northern New Mexico in the early 1940’s, the largest specimen can be seen mounted at the recently opened Oklahoma Museum of Natural History.  For over 50 years this animal’s head remained encased in its field jacket because they had nowhere to put it.  Dr. Wann Langston, the finder and one of the original team, was able to help bring this specimen to public view.  His former student, Kyle Davies, supervised the preparation of the skull.  Another former student, Tom Lehman, published the paper.  Lived 75-65 Ma.

Found around the world, including Antarctica, the Theropods were long-legged, bipedal, carnivorous dinosaurs.  The Carnosaurs are the largest carnivorous land animals ever to walk the Earth.

All but the earliest Theropods could see in stereoscopic vision (eyes face forward).  They had a larger than average brain to body size ratio.  This suggests some intelligence beyond instinct.  A larger brain would have been necessary for the animals to hunt together, especially in the raptors who probably hunted in packs.

Most Theropods had prominent processes on the neck vertebrae giving them a hump.  These would have supported strong neck muscles used tear into or hold onto struggling prey.

A few Theropods grew very long spines from their back vertebra like the Permian Dimetrodon.  Oddly, they are not related.  This is simply a case of parallel (convergent) evolution.  In Spinosaurus, the spines were eleven times longer than an average Theropod.

The tails of many Theropods were stiff.  The prezygapophyses and chevrons are extremely elongated, crossing over many other vertebrae.  A stiff tail aids in bipedal balance and swift rotation of the body.

The skulls of many Theropods are thickened.  Many have small bumps or horns on the nose and eye ridges.  Some may have had boney plates imbedded in the skin for protection.

Theropod’s lower jaw was similar to that of snakes.  A flexible joint in the center of the jaw helped in swallowing large chunks of meat.   T. rex’s huge mouth could gobble up to 500 pounds of meat and bones in one bite!  There are many examples of Hadrosaurs being one of those meals.

Pneumatics

One of the interesting structural aspects of Theropods is pneumatic (air filled) bones.  Many of their bones are hollow or pocketed allowing air to feed the structure directly.  The antorbital fosse (hole in front of the eye) contained a large air sack that pumped oxygen from the nasal cavity through tubes to feed the roof of the mouth and eye.  In some Theropods these tubes also fed the middle ear, throat, and braincase.  The lungs pumped air directly to the neck vertebra and ribs.  A few had air passageways all the way to the middle tail vertebrae.

Most of the bones in birds are air filled.  Birds are direct descendents of very early theropod dinosaurs.  The two have more than 120 similar characteristics, including a wishbone, swiveling wrists, three forward-pointing toes, and hollow leg bones.

The pneumatic bone structure and hollow bones are not exclusive to Theropods and birds.  Archosaurs, Sauropods, Pterosaurs, and Hadrosaurs have similar structures.  This suggests a primitive characteristic lost in the other dinosaurs.

Tyrannosaurus rex - skull cast

(tye-RAN-uh-SAW-rus RECKS)

Pet name: Stan

Period: Late Cretaceous

Location: South Dakota

Collection: George Blasing

Size: 5 feet long

Click the picture for more photos!

Skull & Jaw

Tyrannosaurus rex (meaning tyrant lizard king) is not largest carnivorous dinosaur.  They reached 40 feet long and 20 feet tall.  This skull is 4 feet long.

T. rex’s teeth are for stabbing and cutting.  Their thin length punctured its prey then sliced the meat with the slight curved, jagged back edge, just like a serrated knife. 

T. rex has been found across North America and possibly into Mongolia.  They lived in a humid, semi-tropical environment of open forests and coastal swamps.

Legs and Feet

The tiny arms of T. rex ended in two fingers, which could not reach the animal’s mouth.  Paleontologists still wonder about their use.  They may have been short, but the muscles were large.

With long bipedal strides, the massive rear legs could race toward their prey.  The humerus of Theropods is always less than half the length of the femur (this one is 50 inches long), a common characteristic of running animals.  Paleontologists are debating whether T-rex was a hunter, a scavenger, or both.  The debate centers on whether the animal could run fast enough to catch food, and if the teeth were strong enough to hold onto a struggling victim.

The three toed, sharply clawed feet look like those of birds.

Cretaceous Theropods found in Texas

Acrocanthosaurus: Carnosauria, Early Cretaceous, 35 feet long and 12,000 pounds.

Deinonychus: (fragments only) Dromaeosauridae, Early Cretaceous, 10 feet long and 180 pounds Their retractable claw is 5 inches long.  Besides the 20 foot herbivore Tenontosaurus, Deinonychus would eat anything it could catch and tear apart.  Because this animal is obviously an active and agile predator, the first specimen allowed scientists to re-evaluated dinosaurs’ activity levels in the early 1970’s.  It also confirmed the kinship between birds and dinosaurs. Lived 121-99 Ma.

Dromaeosaurus: (fragments only) Dromaeosauridae, Late Cretaceous, 6 feet long and 100 pounds.

Tyrannosaurus: (fragments only) Tyrannosauridae, Late Cretaceous, 35 feet long and 13,000 pounds, found in the Javelina Formation of the Big Bend.

Albertosaurus: (fragments only) Tyrannosauridae, Late Cretaceous, found in the Javelina Formation of the Big Bend.  30 feet long and 10,000 pounds.  Probably faster and more agile than T-rex.

Ornithomimus: (fragments only) Ornithomimidae, Late Cretaceous, 10 feet long and 200 pounds.  This is one of the bird-mimic dinosaurs. They are toothless omnivores. Found in the Aguja Formation of Big Bend.

Deinonychus antirrhopus - skull cast

(die-NON-eh-kuss AN-ter-OP-us)

Period: Lower Cretaceous

Location: ? (purchased)

Collection: Scott Clark

Size: 14" long x 7" high x 5" wide at rear

Dromaeosauridae: The “Raptors”

Texas has fragments of two “raptors”, Deinonychus and Dromaeosaurus.  Most are relatively small, agile, bird-like Theropods who are noted for the large claw on their hind feet.  While walking or running, the second toe retracts in an upright locked position.  In an attack, the large claw snaps down like a switchblade.  Another characteristic is their backward-curving teeth.

“Raptor” is the common name for Dromaeosaurs which means plunderer.  It refers to the similarity of appearance to birds of prey: hawks and eagles.  Recently found specimens show that some, if not all, Dromaeosaurs had  feathers.  It is speculated birds evolved through early Dromaeosaur line.

They are found on all the continents.  The well known Velociraptor (quick plunderer) is from Asia.

With large brains and good eyesight they made a fearsome predator.  Their three fingered hands and long arms could grasp prey securely.  Slender bipedal legs were built for speed and maybe even jumping.  There is evidence they hunted in packs, probably preferring ambushes and short chases.  Stiffened tails with a flexible joint at the hips insured balance and maneuverability.

Living Mountains

Sauropods are Saurischian dinosaurs, meaning they have a closer relationship to T-rex then Edmontosaur or Chasmosaur.  All Sauropods were herbivores.  Most were large quadrupeds with small heads, very long necks, and very long tails.  The largest group, Titanosaurs, ranged in size from 23 to 130 feet long and could reach 110 tons. The ancestry of Sauropods before the Middle Jurassic is obscure.

Like many dinosaurs, Sauropods often had boney plates imbedded in their skin as body armor.  Occasionally, conical epidermal spines run down their back and tail.

Inhabiting all of the continents, except possibly Antarctica, Sauropods overshadowed the animals around them.  Their sparse presence in the northern continents and abundant in the southern continent of Gondwana is note worthy.  In North America all the Sauropods disappeared during the Middle Cretaceous (105 Ma).  No one knows why.  Shortly before the end of the Cretaceous (70 Ma), Alamosaurus appears in New Mexico, Texas, and Utah.  It looks very much like titanosaurs found in South America.  Evidence shows that the sea levels dropped at this time and a land bridge connected North and South America.  These large animals immigrated to the North.

Mistaken Identities

Sauropods were once thought to be marine creatures.  Scientist could not imagine such a large reptile standing on land unsupported.  After finding leg and foot bones, it became obvious they could walk.  The Sauropods became shallow water creatures, living in lagoons, rivers, and swamps occasionally going onto dry land to lay their eggs.

After the first feet were found, paleontologists believed the stance of the Sauropods was upright.  Then several noted scholars wrote a paper arguing for a sprawled stance similar to modern reptiles.  In Germany an upright mount was dismantled and repositioned to sprawl.  Even though Marsh, in 1910, showed that they had to stand upright, the concept of sprawling dinosaurs persisted until the 1980’s.

  In 1951 and then again in the mid 1970’s a few paleontologists argued that Sauropods were completely terrestrial, like elephants.  With additional information gathered over the years, that viewpoint has been adopted.

The first mounted sauropod (1890s) had a borrowed head.  Even after they determined what head was incorrect for the animal, museums refrained from changing it to keep from looking inept.

“Brontosaurus” is a familiar name for a Sauropod, but the animals are now called Apatosaurus.  In the early days of western U.S. fossil hunting, many partial fossils were found, shipped east, quickly studied, and named.  Two Sauropods were described.  “Brontosaurus” had five sacral vertebrae and Apatosaurus had three.  After further study, paleontologists determined they were the same animal.  As the Sauropod aged, its vertebra fused together appearing to be only three. The first one named, Apatosaurus, claimed all the fossils.  Thus “Brontosaurus” is a juvenile Apatosaurus.  The name “Brontosaurus” is always placed within quotation marks to remind readers of this change.

Head

Compared to the size of their bodies, Sauropods have very small heads.  This gives them the lowest brain size to body size ratio of all the dinosaurs.  This has nothing to do with IQ levels, which can not be measured in fossils.

Based on the teeth types, there are two groups of Sauropods: those with thick spoon-shaped teeth (Camarasaurus, Brachiosaurus) and those with slender peg-like teeth (Diplodocus, Alamosaurus, Malawisaurus).  Determining an animals group is often impossible because most Sauropod fossils are found headless.  The joint between the head and neck is weak making it an easy item for scavengers to carry away.  Without an abundance of heads Sauropods genera are defined by the number and distribution of vertebrae.

Alamosaurus used its peg-shaped teeth to scrape leaves from branches.  The food was not chewed but swallowed whole to be digested in their gut.

Sauropods Nose

One of the odd characteristics of the Sauropod head is their sinuses.  These large cavities are in front of the eye sockets not at the end of the muzzle.  In paintings, the fleshed-out nose is drawn above the cavities.  The belief of aquatic Sauropods dictated this location; no one had actually investigated the evidence.  In 2001, a new theory proposed the sinus cavities were used like those of Hadrosaurs, to make noise.  The study showed the external nose would have been made of cartilage that ran down the top of the skull and opened near the end of the snout.

Vertebrae

The vertebrae of Sauropods are very lightly built with air cavities to reduce density.  They also are strutted like in a modern bridge, tending to lock together, limiting flexibility but adding strength.  For weight and strength, these characteristics are unequaled in any other animal.

The elongated 10 to 16 vertebrae of the Sauropod neck make its length much greater than the animal’s body.  It is possible that most Sauropods could not lift their neck very high off the ground.  Rather they panned side-to-side to find food.  More food could be gathered with the least amount of effort, reducing energy loss.  From the bone evidence, a few Sauropods could lift their heads nearly vertical.  They had to have pumps in their necks to keep the blood flowing to their heads.

The extremely long tails of Sauropods dwarf even the necks.  The earliest animals had 44 tail vertebrae.  The longest tail belongs to Diplodocus, a titanosaur.  It had 80 vertebrae with an additional 40 rod-like elements at the end.  The end of the tail could be flicked to reach speeds breaking the sound barrier, just like a bullwhip.

Legs and Feet

The leg lengths of Sauropods are varied.  Some have longer front legs, others back.  Longer front legs would give the animal the ability to reach higher branches.  Longer rear legs may have allowed for balancing on the rear legs for reaching food or simply maneuverability (a pivot).

Sauropods have five metacarpals (long hand bones) set in a semi-circle on their front feet and walk digitigrade (fingertips). They would have had thick pads like elephants for cushioning.  Over time, the foot structures become simpler.  Ankle bones are reduced to two bones. The phalanges (finger bones) are reduced in number until the last Sauropods may have had only one.  In most cases only the inner finger retains a claw, which eventually vanishes.

The rear feet walk in semi-plantigrade (on the phalanges).  Five toes remain in the back, but the outer two are reduced in size. The three main toes always have claws, not toenails like Edmontosaurus and Chasmosaurus.

Sauropods found in Texas

Pleurocoelus: Early Cretaceous, 50 ft long, 40 tons, N. Central Texas.  Probably made the footprints at Glen Rose, Texas.

Alamosaurus: Late Cretaceous, 80-90 feet long and over 50 tons, from the Javelina formation of Big Bend Texas.  Largest dinosaur of Texas.  Lived 71-65 Ma.

Malawisaurus dixeyi

(mə-LAH-WE-SAWR-us DIC-see-EYE)

Period: Lower Cretaceous

Location: Zambezi Valley, Malawi, Africa

Collection: Dallas Museum of Natural History

Size: 35 feet long

it might have weighed 25,000 pounds

Click the picture for more photos!

Malawisaurus

This mounting is a reconstruction.  Some parts are plaster casts from real bones; some sculpted to represent missing parts.  Malawisaurus comes from Africa, not Texas.  At 35 feet long and 25,000 pounds, this is a small Titanosaur.

Malawisaurus is quite important.  Its similarity to the Andesaurus from Argentina help link Africa and South America before the two continents ripped apart.

Alamosaurus sanjuanensis - humerous

(AL-uh-moh-SAWR-us SAN-hwan-IN-sis)

Period: Upper Cretaceous

Location: Big Bend National Park, Texas

Collection: Texas Memorial Museum at Austin

Size: 5 feet tall

Alamosaurus

This is one of the largest animals to walk on Earth with an estimated length of 80-90 feet and over 50 tons.  Its humerus alone is 5 feet tall.  These animals were so big that only parts of any one became fossilized.  There are no complete articulated skeletons or any complete skulls.  Excavated by Dr. Wann Langston in 1973, the specimen includes this humerus, a femur, all the vertebrae from the base of the neck to the first vertebrae of the tail, and the hip bones.  Because of the manpower and funding restraints, only the humerus, femur, and first vertebra have been prepared.

Alamo is the Spanish word for the cottonwood tree.  These animals were first found near a trading post in New Mexico called the Ojo Alamo.

More Alamosaurus Vertebra

In 1996 Dana Biasatti and Dr. Homer Montgomery of UT Dallas discovered 10 articulated Alamosaurus cervical (neck) vertebrae in Big Bend National Park.  Together they form a 27 foot, well preserved, section of the animal’s neck.  Scott Clark and Larry Millar, of the Boneheads, joined the teams from 1997 to 2001.  They helped dig, jacket, and remove the first vertebrae.  It took 6 men to carry out that one 400 pound stone.

Only 3 bones could be carried out of the desert canyon by manpower.  The largest vertebra, incased in its protective plaster field jacket, weighed more than 1000 pounds.  A Huey helicopter lifted the remaining vertebra to a waiting truck.  A special dinosaur decal,  “Dino-1”, and an American flag decorated the aircraft’s tail donated by Bell Helicopters of Hurst Texas.

A team lead by Dr. Fiorillo will clean, study, and display the fossils in Dallas.  This will take several years.  Because the bones were found in a national park, they remain the property of the park service.  Eventually casts will be displayed in Big Bend National Park.