Friday, September 26, 2014

Allosaurus: The Lion of the Jurassic

You guys will have to forgive me: I didn't post how many days it was until Autumn began and Elephant Appreciation Day. In fact, I had forgotten about fall until someone at church pointed it out! I can't believe the summer's gone already! Depending on where you are in the world, you'll see birds migrating south for the winter, leaves changing colors and eventually falling to the ground, shorter days and perhaps even snow. Here in the part of Utah where I live though, the only change I'm going to expect is a reduce in temperature. The days are also getting shorter. I can't believe fall is here already! I mean, soon we'll be singing Christmas songs! (Actually, I'm already seeing Christmas commercials and movies on TV!). Anyway, before any more time passes, let's get started! Today, I decided to post a fall-related video from the television show Phineas and Ferb. Technically, in this episode, Phineas and Ferb create S'fall. You can watch it below:

Days till:
It is: 17 days till Columbus Day
It is: 35 days till Harvest Day, aka “Halloween”
It is: 46 days till Veterans Day

In the Spotlight:
I've got several goodies this week about the upcoming movie Jurassic World, the fourth Jurassic Park movie. After a few weeks of practically no updates, a rumor has sprouted that that we'll be seeing the first trailer for JW this November!!! You might recall that earlier this year, many JP fans were speculating that we'd be seeing some footage at San Diego Comic-Con. Unfortunately, none was shown. However, Boxoffice Forums speculates that we'll be seeing some footage at the November premiere of the Legendary Pictures film Interstellar. Though it was believed by some that we might get a JW trailer at the premiere of  two later upcoming movies – The Hunger Games Mockingjay Part 1 and Dumb and Dumber 2 – a JW trailer at the Interstellar premiere makes loads of sense considering Legendary Pictures is doing both this movie and JW. However, this doesn't rule out the possibility of JW trailers being shown during the two other movies I mentioned. Interstellar is coming into theaters on November 7th, so hopefully, we'll finally be able to see the first trailer of Jurassic World!

In additional news, director of Jurassic World, Colin Trevorrow posted another picture from Jurassic World that perfectly reflects the movie itself and the time of year we're entering now. This is the picture he posted with the word “Autumn” in the description:

Laying forgotten amid the leaflitter is the East Dock sign from Jurassic Park. Will it return in Jurassic World?
Does this sign lying amid the leaf litter look familiar? It should if you've seen the first Jurassic Park movie! This sign that's supposed to point in the direction of Isla Nublar's East Dock was knocked over by Dennis Nedry's jeep in the first film. This could suggest many different things. Perhaps this picture is just Trevorrow's way of reminding us about the upcoming movie; maybe he's hinting at a trailer due to be released in “Autumn.” Or perhaps this is actually from the movie! Some JP fans have theorized that we'll see this sign in the state seen in Trevorrow's picture in the film. It is believed that some of the film's characters will encounter some of the original locations from the Jurassic Park movies (e.g. the Visitor's Center). Perhaps this is from one of those scenes. If so, this would be the first time in the Jurassic Park movies that a location from previous movies is revisited It might also be part of a flashback. Either way, it's a cool photo.

The update from Jurassic World that I have for you all today is a picture apparently taken by Twitter user Brycenator100. It reveals the inside of the new Visitor Center in the Jurassic World theme park! Here it is below:

Welcome to Jurassic Pa- Oops! I mean Jurassic World!
So what can we gather from this picture? Well, it appears to be rather similar to the Visitor Center from the first film. However, it's going to be different in several ways. You might notice the green wall in the background; this is likely for special effects, like hologram images that are rumored to appear in the film. And in the foreground of the picture, to the left, you can see an information panel labeled “...nosaurus Rex”. I think we all know what the full word is. Of course, I can't be sure, but I think that in the center of the platform in the middle of the picture, we might have the skeleton of a Tyrannosaurus, like in the first movie. Whatever happens, I can't wait to see this movie!

Topic of the Week by Christian Ryan

Meet Allosaurus fragilis, the Lion of the Jurassic
Unless you are a paleontologist or dinosaur enthusiast, it's unlikely that you will have heard of Allosaurus, or recognized it before when you've seen it in various forms of dinosaur pop-culture. Even though this dinosaur might look a little like a lesser-evolved T. rex at first glance, Allosaurus was jam-packed with its own unique specially designed features and abilities that made it an awesome and efficient killing-machine; it was intelligently designed to thrive in the habitat God placed it in 6,000 years ago.

Allosaurus was a very different dinosaur from Tyrannosaurus.
So what is an Allosaurus? Well, first of all, the name Allosaurus (meaning “different lizard”) is one of the largest theropod dinosaurs of the Jurassic habitat; the “lion of the Jurassic”. The average Allosaurus was 28 feet long and stood 8-10 feet from head to toe. Despite its size however, the creature only weighed about 2 ½ tons. The largest confirmed Allosaurus specimen ever found is 32 feet long. As you will find out, life in the Jurassic was tough for an Allosaurus – the prey they hunted was often either really fast, really well-armored or really huge, (and I do mean really huge) and there was competition from other predators for resources. Somehow though, fossil evidence shows us that Allosaurus was the ultimate Jurassic survivor.

Size comparison between several Allosaurus specimens and an Epanterias and a human.
Before we get into the behavior and ecology of this dinosaur, let's learn some basics about its anatomy and the history of its discovery. Allosaurus was discovered during the Bone Wars and was described by paleontologist Charles Marsh in the year 1877. This dinosaur broke the record for being the largest carnivorous dinosaur; the previous title-holder was probably Megalosaurus, a carnivore about 20 feet long. It is classified in the group Carnosauria, and inside of that group it is assigned to the Allosauridae family. For a long time, Allosaurus was portrayed as a creature very similar to T. rex, but smaller. If you have mistook an Allosaurus for a T. rex sometime in the past, you're not alone. Ray Harryhausen – one of the most important stop-motion creators of his time – is quoted for saying,
“They're (T. rex and Allosaurus) both meat eaters, they're both tyrants... one was just a bit larger than the other.”
Nothing could be farther from the truth. Scientists continued to portray Allosaurus as a dwarf T. rex for much of the 20th century until some special discoveries were made in the Cleveland-Lloyd Dinosaur Quarry in Emery County, Utah. Even though the site was described in 1945, major fossil hunting didn't start until 1960. Between the years 1960 and 1965, paleontologists discovered a treasure trove of dinosaur bones, mostly from Allosaurus. In fact, it's estimated that they found at least 46 individuals of the Jurassic predator! This evidence seems to suggest something catastrophic killed and rapidly buried the Allosaurus and other dinosaur species found at the Cleveland-Lloyd Dinosaur Quarry, such as the Genesis Flood. These findings helped us know a great deal more about Allosaurus. It is thanks to these finds that we've been able to piece together the truth about Allosaurus.

For a long time, Allosaurus was assumed to be a slightly smaller version of a T. rex.
Contrary to many depictions through much of the 20th century, Allosaurus walked with its body held forward and its tail off the ground. It wasn't a sluggish predator either; instead, it was fast and agile. There are two, possibly three, known species of Allosaurus known to science, Allosaurus fragilis (the type specimen), Allosaurus europaeus and possibly Allosaurus jimmadseni, with other potential species coming, going and being hotly debated over the years. To keep it simple, I will stick to mostly talking about A. fragilis unless otherwise specified. As its species name suggests, europeaus fossils have been uncovered in Europe, Portugal to be precise. Jimmadseni fossils have been found in Tanzania, Africa and A. fragilis fossils are found in the western United States.

The yellow area represents the Morrison Formation; the dots represent where notable Allosaurus specimens have been discovered; plus marks represent the location of several Allosaurus fossil finds.
Allosaurus fragilis was one of the apex predators of its Jurassic domain, which is why it is sometimes nicknamed the “Lion of the Jurassic”. The western United States where this dinosaur lived (represented by the Morrison Formation) were very different in the pre-Flood Jurassic world than it is now. Instead of being a dry desert, these areas were much more lush. Fossil evidence suggests that this area was filled with river-lining forests of conifers and ferns, gallery forests and fern prairies. Roaming these areas was a vast array of herbivorous dinosaurs, from the diminutive and fleet-footed Dryosaurus and Othneilosaurus to the large sauropods like Apatosaurus, Brachiosaurus, Camarasaurus and Diplodocus. Other herbivores like the well-known Stegosaurus also made their home here. With ample herbivores, there's no doubt that there was a load of carnivores able to hunt many of them down, and Allosaurus wasn't the only one. Ceratosaurus was a smaller carnivore that lived in the region. Like Allosaurus, it had a crested head, but it might have been more of an opportunist than the aforementioned carnivore, as fossil evidence reveals it ate a wide variety of prey. Another carnivore Allosaurus had to compete with was Torvosaurus – on average, this predator was larger than Allosaurus and could have caused a major threat. In order for these three carnivores to coexist, they must have filled different ecological niches within their environment.

Torvosaurus was a major competitor of Allosaurus. In Europe, Allosaurus was smaller than this dinosaur.

Ceratosaurus would always have to have been wary of Allosaurus, because it was smaller than the Lion of the Jurassic.
But what's the point of living in a place with lots of prey without the equipment to bring it down? Well, Allosaurus had just that! As I've said before, this dinosaur was faster than Tyrannosaurus, meaning it would have been able to chase after prey for a longer period of time. Scientists predict Allosaurus could run up to 30 mph in short bursts. This dinosaur was ready to bring down its prey once it was in range. Allosaurus' jaws bore 4-inch teeth; each tooth was re-curved and serrated both front and back, just like a steak knife. Like other theropods, the teeth are specially designed to break and fall out quite often. This is because the teeth are replaced continuously to always insure Allosaurus has a set of sharp teeth ready for action. In addition to its teeth, Allosaurus also has a set of three sharp claws on each hand.

Allosaurus had a lot of herbivorous dinosaurs to prey on.
Now it's time for an Allosaurus to go on the hunt! Even though studies reveal it likely had relatively poor hearing capabilities, it seems that this dinosaur could hear low frequency sounds very well. This is useful when tracking down herds of large dinosaurs that would have been making low frequency noises with each footstep. A good sense of smell and a wide range of vision would have helped it pinpoint the location of its target. When an Allosaurus attacked, you can be sure that other dinosaurs would have been terrified! Once close enough, Allosaurus would have put its claws and teeth to work. Remember when I talked about this creature's teeth and how they are pointing backwards? This is to ensure that the victim can't escape without suffering devastating slash-like wounds. Scientists were curious about Allosaurus' bite force. Surely an animal weighing 2 ½ tons has a bone-crushing bite, right? After running tests, paleontologists were in for a surprise when their calculations suggested this dinosaur had a bite force of 805-2,148 newtons! This is less than a lion; in fact, it's rather on par with a leopard. Ironically, Allosaurus' skull, the scientists found out, could withstand great amounts of pressure that would be expected for a predator that's tackling active prey.

Allosaurus had a bite force weaker than a lion!
However, Allosaurus didn't need a strong bite to bring down prey! You see, Allosaurus had teeth designed for slicing through flesh, unlike the bone-crunching Tyrannosaurus, and this (combined with this dinosaur's bite force and skull design) suggests that it actually used its head like an ax when attacking prey. It would probably latch onto prey with its jaws and begin slashing flesh away with its teeth without breaking the prey's bones. This way, after making enough devastating damage, Allosaurus could take a step back and wait for the prey animal to succumb to its injuries, suffering from a massive amount of blood loss and shock. Then Allosaurus could go in to start the feast. Of course, it's likely Allosaurus could have used other methods to bring down prey as well.

Opening its jaws nice and wide, Allosaurus was able to cut deep wounds into prey by slashing into it with its teeth, sort of like an ax.

Even using this technique, the 2 ½ ton Allosaurus would have no conceivable way of tackling the large adult sauropods. However, we have evidence that sauropods were at least scavenged upon by Allosaurus, as several sauropod fossils have gouges and bite marks caused by Allosaurus. But there might have been a way for these predators to tackle creatures like the 35-ton Apatosaurus – maybe they worked as a team. This way, only the largest adults could be safe from this predator. Evidence for pack-hunting in this species comes from fossil sites such as the Cleveland-Lloyd Quarry in which these dinosaurs have been found in the same location. As you might recall, several tens of allosaurs have been uncovered there, ranging from adults to youngsters. It's possible that during the Genesis Flood, several packs of Allosaurus would have become trapped on islands that formed as the Flood waters rose upon the earth as it describes in Genesis 7.

This is a good time to bring up Allosaurus' small horns on top of its head. Paleontologists aren't sure what they were used for, but they were likely covered in a horny sheath in life and brightly colored, perhaps to attract mates or used in species recognition. Species recognition would have been very important to these dinosaurs if they at least occasionally hunted in packs.

An Allosaurus attacks a mother Stegosaurus and her young.
As I mentioned before, Allosaurus is really an amazing survivor! These dinosaurs often had tough lives – individuals of this species are often discovered with nasty injuries. Several pathologies have been found, including:
  • Willow breaks in ribs
  • Humerus and radius fractures
  • Distortion of joint surfaces in foot due possibly due to Osteoarthritis (yes, dinosaurs had this disease too)
  • Amputation of a chevron and foot bone (possibly caused by bits)
  • Coossification of vertebral centra near end of tail
  • Etc.

There is an Allosaurus vertebrae with a hole punched into it; the tail spike of a Stegosaurus fits the hole perfectly, suggesting that it wasn't always easy for Allosaurus to bring down these creatures. The interesting thing about these injuries is that, believe it or not, many were in the process of healing (this includes the Stegosaurus-inflicted injury). This means that the injuries happened while the Allosaurus were alive and they continued to live for months, or even years after the injuries occurred! Many of the pathologies suffered by these and other dinosaurs would be life-threatening to a human. One Allosaurus specimen, named Big Al, is a sub-adult individual who suffered from at least 19 deformities caused either by disease or injury, including broken ribs (which were in the process of healing before he died) and even a swelling toe infection! Paleontologists believe Big Al was about six years old at the time of his death.

Big Al was one of the most complete Allosaurus skeletons ever found; by the time of his death, he had several broken bones and even a toe infection.
And as if this isn't impressive enough, there's another Allosaurus discovery that took place in the western United States – during the Bone Wars, the lower jaw bone of a dinosaur was discovered, but it was so distorted, that paleontologists couldn't identify it for a long time. Finally, they were able to determine the jawbone's owner was an Allosaurus. The jawbone was distorted to the fact that it was broken. And again, the jawbone was in the healing process at the time the animal died, months or years after the injury was inflicted. Scientists aren't sure how this Allosaurus broke its jaw, but some have suggested it happened when tasseling with prey, such as the whiplash-like tail of a sauropod as is portrayed in Discovery Channel's Dinosaur Revolution. Isn't it amazing? Even 4,350 years ago (years before veterinarians), God designed these animals with the ability to heal themselves from these horrific pathologies.

This Allosaurus suffered with a broken jaw for months or even years before his death.
As Ceratosaurus wasn't as large and Torvosaurus didn't appear to be as common, nothing could have taken Allosaurus' title as one of the apex predators of the Jurassic habitat . . . no living creature that is! The fossils of Allosaurus that we find buried in rock layers are all that remain of these creatures that lived in the world before the Genesis Flood. At the time of the Flood, around 4,350 years ago, the Bible records that all land-dwelling, air-breathing creatures perished in the waters of a global Flood except those that were on board Noah's ark. This would have included dinosaurs. But we also know that these dinosaurs were later killed off after the Flood by environmental changes and also probably human's hunting them and forcing them from their natural habitat. The last dinosaurs soon met their doom.
Fossil tooth marks prove Allosaurus at least scavenged on the carcasses of sauropods like Apatosaurus. They probably hunted juveniles of the species as well.
Allosaurus was one of the top predators of Jurassic Portugal, Tanzania and western North America. And as we just learned, it was beautifully designed to thrive in its dangerous world. Even though life (after the Fall of Man) was tough for these creatures, the species was able to survive. What an impressive and wonderfully designed dinosaur.

This is Ebenezer, the Creation Museum's Allosaurus skeleton. This mighty Allosaurus is a wonderful reminder of the devastating Flood that destroyed the pre-Flood world 4,350 years ago.


Disclaimer: Many (or in some cases all) of the photographs and images above are not mine. If you own one or more of them and would like them to be removed, politely let me know via one or both of the email addresses above.

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