Ferocious T. Rex Cousin Was Europe's Largest Land Predator

[Buster's Uncle]

Ferocious T. Rex Cousin Was Europe's Largest Land Predator
LiveScience.com
By Tia Ghose, Staff Writer  4 hours ago



The fearsome Torvosaurus gurneyi was likely a top predator of its day and was only slightly smaller than the mighty T. rex



A massive, meat-eating dinosaur that roamed a Jurassic-era coastline has been unearthed in Portugal.

The big-clawed, sharp-toothed newly discovered species, dubbed Torvosaurus gurneyi, may be the largest land predator from the period ever found in Europe.

"It's a dinosaur that is quite similar to T. rex," with huge teeth and an elongated snout, said study co-author Christophe Hendrickx, a paleontology doctoral candidate at the Universidade Nova de Lisboa in Portugal.


Dino-rich region

Lourinhã, Portugal, is a fossil-rich region where sheer cliffs overlook the shoreline. During the late Jurassic Period, the area boasted a vast, steamy river plain rich with lush vegetation and a diverse array of dinosaurs. Last year, scientists described several well-preserved dinosaur embryos in Lourinhã from the genus Torvosaurus but could not identify the species discovered at the site.

The new dinosaur was first unearthed in 2003, when an amateur paleontologist uncovered part of a jawbone. A shinbone, teeth and fragments of tail vertebrae were also discovered later. Scientists initially thought the bones came from Torvosaurus tanneri, a massive land-based predator that lived in North America some 150 million years ago.

But Hendrickx and his colleague Octávio Mateus, a paleontologist also at the Universidade Nova de Lisboa, took a closer look at the skeletal remains and determined that they came from the newly named species.


European behemoth

The European behemoth was a theropod, a suborder of meat-eating dinosaurs that includes the mighty Tyrannosaurus rex. Though T. gurneyi grew to 33 feet (10 meters) long and weighed 4 to 5 tons, it was still smaller than T. rex, which was 40 feet (12 m) from head to toe.

Its huge, bladelike, 4-inch-long (10 centimeters) teeth confirm the massive dinosaur was a carnivore, Hendrickx told Live Science.

"Most likely, it was a predator," Hendrickx said, and it probably hunted large, live prey, as there was a wide variety of herbivorous dinosaurs during that time. However, it may have also been a scavenger, he added.


Big creatures

The new discovery changes the picture of European dinosaurs at the time. Back then, Europe was an archipelago of large islands, and animals often evolve to be smaller on islands. In fact, many of the dinosaurs in the late Jurassic Period in Europe show signs of dwarfism, Hendrickx said. (The Jurassic lasted from 199.6 million to 145.5 million years ago.)

But when it came to size, Torvosaurus gurneyi could hold its own against the giant super predators of North America, showing that "large dinosaurs did exist in Europe by the end of the Jurassic," Hendrickx said.

The fossil discoveries also suggest that the dinosaur embryos discovered last year belonged to T. gurneyi, Hendrickx said.

The findings were published today (March 5) in the journal PLOS ONE.


http://news.yahoo.com/ferocious-t-rex-cousin-europes-largest-land-predator-124016774.html

[Buster's Uncle]

Huge new dinosaur in Portugal was predator king: study
AFP
By Naomi Seck  3 hours ago



Fact file on a new dinosaur discovered in Portugal, the largest land predator found in Europe (AFP Photo/)



Washington (AFP) - A new dinosaur species discovered in Portugal dominated the food chain 150 million years ago -- the Tyrannosaurus Rex of its time, researchers said Wednesday.

The new species is the largest land predator discovered in Europe and one of the largest worldwide of the Jurassic era, said authors Christophe Hendrickx and Octavio Mateus of the Universidade Nova de Lisboa and Museu da Lourinha.

The Torvosaurus gurneyi, like T. Rex, was a bipedal carnivore with blade-like teeth more than 4 inches (10 centimeters) in length, they said in a report published in the US journal PLOS ONE.

"This was clearly a fierce predator," Mateus told AFP. "Wherever he arrived, he was the owner and master. No one could rival Torvosaurus during the late Jurassic. This is the equivalent of T. rex but 80 million years before."

The scientists estimate Torvosaurus gurneyi grew up to 33 feet (10 meters) long and weighed some 4 or 5 tons. Its skull measured nearly four-feet (115 centimeters) long, smaller than the T. Rex, but not by a huge margin.

The fossils found in Portugal closely resemble those of a North American dinosaur -- the Torvosaurus tanneri -- and indeed at first the scientists thought the two specimens must be from the same species.



Geologist Bill Simpson cleans Sue, a 67-million-year-old Tyrannosaurus Rex on display at the Field Museum on November 12, 2013 in Chicago (AFP Photo/Scott Olson)


But upon closer analysis of the bones, the researchers determined the species must have evolved separately from the two sides of the proto-Atlantic Ocean over a few million years.

Mateus said it's hard to know how different the two species would have looked when they were living -- there may have been differences in coloring or behavior that would have easily distinguished them.

From the fossil record, the differences are more subtle.

The North American species has 11 or more teeth on its upper jaw, compared to fewer than 11 for the Portuguese dinosaur, the researchers explained. And the mouth bones are shaped and structured differently.


- A 'game-changing' predator -

Discovering such a large predator in this era could really be "a game changer" in terms of how scientists think of the Jurassic food chain, explained University of Kansas paleontologist David Burnham, who was not involved in the research.

"These things were living with giant plant-eating dinosaurs," or sauropods, Burnham explained, herbivores too big for other common Jurassic predators, like the Allosaurus, to attack.

But if the estimates of the new Torvosaurus are right, he said, the carnivore was certainly big and fast enough to catch a small sauropod.

"The blade-like teeth of Torvosaurus are particularly nasty since they would seem to indicate a slash-shred strategy," he added.

The new species is also of interest to paleontologists, because it gives a more detailed picture of the interactions and connections between North America and Europe at the time.

"Finding another (Torvosaurus) species in Portugal is pretty cool, because this is additional evidence that shows a similarity in Jurassic dinosaurs in Europe and in North America," adding to finds of a Stegosaurus and an Allosaurus in both the US West and Portugal, said Ken Carpenter, paleontologist at Utah State University.


http://news.yahoo.com/huge-dinosaur-portugal-predator-king-084825730.html

[Rusty Edge]

Interesting.
I'm not sure about their conclusions, though.

For example, Condors and some of the other vultures are among the largest flying birds, and while they are certainly meat-eaters with vicious bites, they aren't exactly predators.
They are large because they conserve energy. They are very efficient gliders. They have the most acute sense of smell among birds, so that they can easily find food.

Or consider turtles and tortoises, the contemporaries of the dinosaurs, so perfect that they have survived to this day virtually unchanged. The largest ones are vegetarians. The largest meat eaters aren't the most active ones. It's the snapping turtles and the alligator snapping turtles- ambush predators who conserve energy. They have vicious bites, too.

Other reptiles to consider are the crocodilians, who are both scavengers and ambush predators. They go way back, too.

The thing that always struck me about the T. Rex, and this dinosaur in particular, is the ratio of the nasal cavity to the brain cavity.  It must have had an incredible sense of smell.
I bet it could have lived pretty well scavenging whatever washed up upon the beach, and also detecting the eggs of other creatures, even if they were buried in sand.

 If a concerned parent showed up to defend the nest, well, this beast looks like it could stand it's ground, and that would save it a lot of energy trying to run down prey, now wouldn't it? It would be like swimming too close to a snapping turtle... CHOMP!  If it got in a couple of vicious bites, and the parent dino ran away and died over night like a cold blooded animal, well T. gurneyi has the nose to track it down for the next day's leisurely feast.

[Buster's Uncle]

Tightly reasoned - but do you think it's safe to make any assumptions about the efficiency of saurian sense of smell organs? 

And there's evidence that some of them were lukewarm-blooded, which could no modern reptile has going, and could change predatory strategies significantly.  Maybe.

[Rusty Edge]

True.
I'm presuming a mix of cold and warm blooded plant eaters. Also I don't know about saurian olfactory efficiency.

But it sure looks to me like these guys had a well developed sense of smell compared to their contemporaries, or compared to their other senses.

Actually, what I described sort of applies to the bears I've had the pleasure and privilege to watch in Alaska. They have a refined sense of smell.

The biggest brown bears  are the most efficient. They find a spot in the stream where the salmon have to come to them. They use their sense of smell to tell the males from the females. They catch the females, eat the heads for the brains, the skin for the layer of fat attached to it, and the eggs. All of the concentrated fats, then they catch the next one.  When the salmon aren't running, you might find them digging tubers in the meadows, digging clams on the beach, or scavenging there.

The only predators in North America which are bigger than the coastal Alaskan Brown bears or the ones on Kodiak island are the polar bears. They use their sense of smell, too. They ambush the seals & beluga whales at their breathing holes.

So the more I think about it, there seems to be a correlation with large size, keen sense of smell, and efficient ambush predation.


Maybe my problem is a lack of imagination here. I have trouble imagining these two legged dinosaurs running ( although hopping like kangaroos would be way cool ).   Too easy to trip on anything but a grassland or beach, and animals that heavy hate to fall, they might not be able to get back up.

Another issue is the way that large animals like draft horses and elephants, bearing all of that weight on their feet,  are sensitive to tremors in the ground. Elephants can sense other elephants stomping and running miles away.

I'm not sure how these multi-ton monsters could be in an area without all of their potential prey knowing it, unless they moved slowly and carefully, or unless they were something like crocodiles, that you didn't have to run from, just stay out of their way, because they don't really chase you.

[Buster's Uncle]

You make enormous sense.  At that scale falls could just break everything, too.

[Rusty Edge]

This got me digging into the T. Rex .

Based upon x-rays of various skulls, comparing the size of the brain lobe which processes olfactory sensory input, nasal cavity and the overall brain size, it seems that both T.Rex and velociraptor had highly developed senses of smell, far above the plant eaters. One article comparing them to bloodhounds. So I guess that while they may not have had mammalian olfactory efficiency, size matters.

Another theory is that the young and the old may have had different food sources, avoiding competition.  Apparently bite force increased tremendously with size, the head in general growing more and larger teeth and bone.

There is some binocular vision, a little more than a hawk has. There is 6 times the brain size for other dinosaurs of this size. That supports a predator theory, at least at some stage of it's life.

 Of course it seems to me the binocular vision might develop as a way better depth perception, and safer walking/trotting. Orangutans have great binocular vision, not because they're predators, but because a mistake in depth perception could mean a lethal fall.

At Wikipedia I found this "cow tipping" theory of triceratops predation rather original, and strangely plausible-

David A. Krauss and John M. Robinson proposed that Tyrannosaurus could have used a hunting strategy similar in concept to “cow tipping” against Triceratops, where the Tyrannosaurus would ambush and knock the Triceratops over to fall on its side. This strategy, according to the Krauss and Robinson could explain the unique characteristics of Tyrannosaurus. Tyrannosaurus’ small, yet strong arms could have been adapted to grasp onto the back of Triceratops while pushing with its pectoral region, its large clawed feet would have given it better traction, its large head could have been used to tip the Triceratops over and its large mouth and bone piercing teeth would have made bites to the side more efficient and deadly. When the Triceratops had fallen over to its side, Tyrannosaurus would then bitten it at the rib cage; killing it. Krauss and Robinson would back up their proposal through physical analyses; finding that Tyrannosaurus moving at moderate speed could have generated enough force to topple Triceratops and would have only taken 2-3 seconds. The study states that a Tyrannosaurus impacting the Triceratops at a conservative estimated speed of 7.5 meters per second would have enabled it to topple Triceratops without injuring itself, though there could be some variance depending on the sizes of the animals (Tyrannosaurus could have attacked a smaller Triceratops). What’s more, their study noted that Triceratops would have experienced some difficulty quickly getting back up from being toppled on to its side. According to the study, modern day analogues of Triceratops such as rhinoceros, camels and large bovids, experience the same kind of difficulty, taking 3-10 seconds to recover. But Triceratops may have experienced more difficulty due to its frill. According to the study, Tyrannosaurus arms were adapted for this strategy, pushing the prey with its chest while gripping it with its arms reduced the chance of the prey slipping away while being pushed. The arms, being short yet strong reduced the chance of joint injury during this struggle. Also having more of the arm’s power concentrated on its flexors instead of the extensors, were ideal since it would have had to flex its arms to keep its prey close. When the Tyrannosaurus is pressed against the side of Tricieratops, its arms were at the right height to reach the spine of the Triceratops, providing a place to grip on. Furthermore, Krauss and Robinson suggest that this strategy would have been effective against other large ceratopsians and because the attack was done through an ambush, Tyrannosaurus would not have needed to compete in speed.[

So maybe T Rex used it's sense of smell to go cow tipping at night!