If you are like most people who live in a country which uses a Daylight Savings Time (or DST) regime, you have probably wondered, at least once, what the purpose for this seemingly weird practice is. Well, in case you don't know, I am now going to explain to you what DST is, the history of it, and why we now use it.
You see, most people tend to wake up long after Sunrise (now, come on, don't be afraid to admit that you like sleeping in!). Therefore, they are most active in the evening, after Sunset. Because the Sun has now gone down, they need to get light from artificial sources, such as light-bulbs. And, obviously, this wastes energy. So, the governments of several countries around the world have now implemented a new system of maintaining their clocks, which is known as Daylight Savings Time, or DST.
At some time during the year, usually near the beginning of Spring, people move their clocks forward, one hour. That way, it would help them save energy, because there would be more sunlight available for them to use, when they wake up, later. For example, if it is 8:00 PM, they would adjust their clocks to 9:00 PM. That way, the clock would say, "9:00 PM", even though, if you look outside, there would still be just as much daylight as there would be, if it were 8:00 PM. In other words, the main purpose of DST is pretty much to get people to use as much sunlight as possible, so that they can save energy.
The concept of Daylight Saving Time has a very long and interesting history. In the 18th Century, Benjamin Franklin first came up with the idea of Daylight Savings Time. However, he never formally published his ideas, and, so, they were then forgotten.
Later on, in 1895, the New Zealand entomologist Dr. George Vernon Hudson once again proposed the idea of DST. He then submitted a paper, advocating his viewpoint, to the Wellington Philosophical Society, for publication. After the town of Christchurch, New Zealand showed considerable interest in his new idea, he wrote another paper, advocating it, in 1898.
The English golfer William Willett also independently came up with the concept of Daylight Savings, in 1905. Willett noticed how many people in his city slept through the daylight hours, and thus needed to use more artificial light, in the evening. Willett then took his proposal, to the British Parliament. The first bill advocating this position was was introduced to the House of Commons, on 12 February, 1908. However, this bill never became a law. Willett then continued to advocate his idea of Daylight Savings Time, until his death, in 1915.
As a result of this, Daylight Savings Time is now used by many different countries, all over the world, including the United States, which first started to use it, in 1918. In the United Kingdom, Daylight Savings Time is also known as British Summer Time (or BST).
So, in conclusion, Daylight Savings Time really is a fascinating subject, in my opinion. I also hope that you now have a better idea, of how DST works.
Wednesday, May 30, 2012
Friday, May 25, 2012
The Anatomy of Troodontids
As you can obviously tell, from the name of my blog, troodontids are among my absolute favourite dinosaurs. Therefore, it should come as no wonder that I am very interested in them. One of the most fascinating topics surrounding troodontids, in my opinion, is their very unique anatomical structure, and what ecological functions it might possibly have served.
Obviously, any theories about an extinct animal's behaviour must start with the creature's anatomy. As for troodontids, they have a very uniquely-specialized body configuration, which, I think, really is very fascinating. For starters, most troodontids had a long, thin snout. Some species, such as Troodon, had many small teeth, with very large serrations, like those of modern-day iguanid lizards. Others, such as Byronosaurus, had teeth with no serrations, at all. However, despite these differences in tooth morphology, overall, troodontids' jaws were mostly similar.
One of the most distinctive characteristics of troodontids is their eyes. Most troodontids had huge eyes. In Troodon, the eyes were 2 inches wide. Although we do not know exactly what purpose such large eyes might have served, I have now come to the conclusion that troodontids were most likely nocturnal, and that those huge eyes probably helped them to hunt for their prey, at night.
Ears are another puzzling aspect of troodontid anatomy. Unlike any other non-avian dinosaurs, troodontids actually had asymmetrical ears; i.e., the left ear was placed higher up, on the head, than the right ear was. While there were no other Mesozoic dinosaurs with this very curious adaptation, there is one group of animals living today that appears to be eerily similar, to troodontids, in this respect. That is the owls. Like troodontids, owls also have asymmetrically-aligned ears, with one ear being higher up on the head, than the other. This is an adaptation that helps owls to listen carefully to small prey, at night. Although we have no way of knowing for sure, without a time-machine, that troodontids might also have used this adaptation for similar purposes certainly cannot be ruled out.
Another distinctive feature of the Troodontidae is the claws on their second toes. Just like the dromaeosaurids, troodontids most likely used their "sickle-claws" to help them kill their prey. I imagine it would be quite useful for disemboweling large prey. Then again, it could also be used to subdue smaller prey.
Like other maniraptorans, troodontids are believed to have possessed feathers. In my opinion, this makes perfect sense, due to their very close relationship to birds. We also have some direct fossil evidence of this, since several fossils of small troodontids have been preserved, with some impressions of feather-like structures, in the rocks that were surrounding them.
All in all, troodontids really are a very fascinating group of dinosaurs, and I will also be blogging more about them, later on.
Obviously, any theories about an extinct animal's behaviour must start with the creature's anatomy. As for troodontids, they have a very uniquely-specialized body configuration, which, I think, really is very fascinating. For starters, most troodontids had a long, thin snout. Some species, such as Troodon, had many small teeth, with very large serrations, like those of modern-day iguanid lizards. Others, such as Byronosaurus, had teeth with no serrations, at all. However, despite these differences in tooth morphology, overall, troodontids' jaws were mostly similar.
One of the most distinctive characteristics of troodontids is their eyes. Most troodontids had huge eyes. In Troodon, the eyes were 2 inches wide. Although we do not know exactly what purpose such large eyes might have served, I have now come to the conclusion that troodontids were most likely nocturnal, and that those huge eyes probably helped them to hunt for their prey, at night.
Ears are another puzzling aspect of troodontid anatomy. Unlike any other non-avian dinosaurs, troodontids actually had asymmetrical ears; i.e., the left ear was placed higher up, on the head, than the right ear was. While there were no other Mesozoic dinosaurs with this very curious adaptation, there is one group of animals living today that appears to be eerily similar, to troodontids, in this respect. That is the owls. Like troodontids, owls also have asymmetrically-aligned ears, with one ear being higher up on the head, than the other. This is an adaptation that helps owls to listen carefully to small prey, at night. Although we have no way of knowing for sure, without a time-machine, that troodontids might also have used this adaptation for similar purposes certainly cannot be ruled out.
Another distinctive feature of the Troodontidae is the claws on their second toes. Just like the dromaeosaurids, troodontids most likely used their "sickle-claws" to help them kill their prey. I imagine it would be quite useful for disemboweling large prey. Then again, it could also be used to subdue smaller prey.
Like other maniraptorans, troodontids are believed to have possessed feathers. In my opinion, this makes perfect sense, due to their very close relationship to birds. We also have some direct fossil evidence of this, since several fossils of small troodontids have been preserved, with some impressions of feather-like structures, in the rocks that were surrounding them.
All in all, troodontids really are a very fascinating group of dinosaurs, and I will also be blogging more about them, later on.
The MacRae Films: A Mystery Within A Mystery
In my last post about the Loch Ness Monster, I pointed out that a few sightings apparently seem to describe mammalian features, which support the long-necked pinniped theory. I am now going to discuss one of these encounters, which I consider to be among the most fascinating.
In the 1930s, a physician named Dr. MacRae apparently recorded 2 films of lake monsters, on video. One of them was at Loch Ness, and the other one was at Loch Duich, which is a sea loch, located on the coast of Northwestern Scotland. The creatures seen in both of the films are very similar. The one from Loch Duich seems to show a long-necked creature with a hairy mane covering its neck, resting partially on the shore, in some seaweed. The one from Loch Ness appears to show a creature with a long neck, a bulky body, and two horn-like projections on its head, frolicking in the water. This creature also has a mane, just like the one at Loch Duich.
In my opinion, these two films provide very good corroboration to my hypothesis that Nessie is some unknown species of long-necked pinniped, since manes are, of course, made out of hair, and only mammals have hair. Therefore, these 2 films, if they can be found, could offer very good evidence, for my hypothesis.
However, the main problem with these films is that they are, quite simply, nowhere to be found! Dr. MacRae, of course, passed away a very long time ago, so we obviously cannot go to him, for more information. Apparently, Dr. MacRae's family is keeping both of the films, in a secret location. However, the Loch Ness Monster researcher Frank W. Holiday did manage to interview somebody who was close to Dr. MacRae, about the films. The information that Holiday received differed very much, from the information that I have just written, above. According to Roy P. Mackal, Holiday found out that the film which was supposedly shot at Loch Ness never even existed, and that only the Loch Duich film was being kept, with Dr. MacRae's family. Obviously, it's no wonder that this whole situation is incredibly confusing!
Now, personally, I am very interested in both of the MacRae films. I feel that, if they are ever recovered, they could help very much in solving one of the world's greatest mysteries. And, as I mentioned earlier, they might even provide more corroboration to my hypothesis that the Loch Ness Monster is a long-necked pinniped.
In conclusion, only one thing is for sure: Both of the films that were supposedly recorded by Dr. MacRae in the 1930s are incredibly interesting, and I really hope to find out more information, about them, soon!
In the 1930s, a physician named Dr. MacRae apparently recorded 2 films of lake monsters, on video. One of them was at Loch Ness, and the other one was at Loch Duich, which is a sea loch, located on the coast of Northwestern Scotland. The creatures seen in both of the films are very similar. The one from Loch Duich seems to show a long-necked creature with a hairy mane covering its neck, resting partially on the shore, in some seaweed. The one from Loch Ness appears to show a creature with a long neck, a bulky body, and two horn-like projections on its head, frolicking in the water. This creature also has a mane, just like the one at Loch Duich.
In my opinion, these two films provide very good corroboration to my hypothesis that Nessie is some unknown species of long-necked pinniped, since manes are, of course, made out of hair, and only mammals have hair. Therefore, these 2 films, if they can be found, could offer very good evidence, for my hypothesis.
However, the main problem with these films is that they are, quite simply, nowhere to be found! Dr. MacRae, of course, passed away a very long time ago, so we obviously cannot go to him, for more information. Apparently, Dr. MacRae's family is keeping both of the films, in a secret location. However, the Loch Ness Monster researcher Frank W. Holiday did manage to interview somebody who was close to Dr. MacRae, about the films. The information that Holiday received differed very much, from the information that I have just written, above. According to Roy P. Mackal, Holiday found out that the film which was supposedly shot at Loch Ness never even existed, and that only the Loch Duich film was being kept, with Dr. MacRae's family. Obviously, it's no wonder that this whole situation is incredibly confusing!
Now, personally, I am very interested in both of the MacRae films. I feel that, if they are ever recovered, they could help very much in solving one of the world's greatest mysteries. And, as I mentioned earlier, they might even provide more corroboration to my hypothesis that the Loch Ness Monster is a long-necked pinniped.
In conclusion, only one thing is for sure: Both of the films that were supposedly recorded by Dr. MacRae in the 1930s are incredibly interesting, and I really hope to find out more information, about them, soon!
Friday, May 18, 2012
A New Dromaeosaurine from the Early Cretaceous of Utah!
Hello! If you'll remember, my last blog post was posted about a month ago, and it was about the Loch Ness Monster. Well, about 3 days ago, something very special happened. A new dromaeosaurid species, Yurgovuchia doellingi, was officially described and named, in the scientific journal PLoS ONE. The paper, which was authored by Phil Senter, James Kirkland, Donald DeBlieux, Scott Madsen, and Natalie Toth, stated that this dinosaur is known only from a single specimen, so far, which consists of a partial post-cranial skeleton. The fossils were discoved at a location known as "Don's Place", in Utah, where Don DeBlieux found them, in 2005. This bone bed is located in the Cedar Mountain Formation. The fossil remains probably date to the Barremian stage of the Early Cretaceous period, from about 135-125 million years ago.
Many other deinonychosaurs are also known, from this formation. Perhaps the most famous is the giant Utahraptor, which, as of now, is the largest known dromaeosaurid. The troodontid Geminiraptor was also discovered there, as well as the small coelurosaur Nedcolbertia. An unnamed velociraptorine dromaeosaurid has also been discovered, in this geological formation.
The genus name, Yurgovuchia, is derived from yurgovuch, a word in the Ute Native American language that means "coyote". The authors chose this name, because they presumed that this species perhaps would have occupied a relatively similar ecological niche, to the modern-day coyote. The species name, doellingi, honors the geologist Helmut Doelling, who has done a lot of field work, in the same area where Yurgovuchia was discovered.
In the paper, the authors carried out a phylogenetic analysis, and they then came to the conclusion that Yurgovuchia most likely belongs to the dromaeosaur subfamily Dromaeosaurinae, along with Utahraptor, Achillobator, and Dromaeosaurus.
Yurgovuchia is the first dromaeosaurid to be described and named in 2012. It is obviously a very important scientific discovery, which will hopefully shed some new light, on the evolution of the Dromaeosauridae.
Many other deinonychosaurs are also known, from this formation. Perhaps the most famous is the giant Utahraptor, which, as of now, is the largest known dromaeosaurid. The troodontid Geminiraptor was also discovered there, as well as the small coelurosaur Nedcolbertia. An unnamed velociraptorine dromaeosaurid has also been discovered, in this geological formation.
The genus name, Yurgovuchia, is derived from yurgovuch, a word in the Ute Native American language that means "coyote". The authors chose this name, because they presumed that this species perhaps would have occupied a relatively similar ecological niche, to the modern-day coyote. The species name, doellingi, honors the geologist Helmut Doelling, who has done a lot of field work, in the same area where Yurgovuchia was discovered.
In the paper, the authors carried out a phylogenetic analysis, and they then came to the conclusion that Yurgovuchia most likely belongs to the dromaeosaur subfamily Dromaeosaurinae, along with Utahraptor, Achillobator, and Dromaeosaurus.
Yurgovuchia is the first dromaeosaurid to be described and named in 2012. It is obviously a very important scientific discovery, which will hopefully shed some new light, on the evolution of the Dromaeosauridae.
Sunday, April 22, 2012
What is the Loch Ness Monster?
Recently, I have developed an interest in cryptozoology. In case you don't know, cryptozoology means "the study of hidden animals". In other words, it is the study of cryptids. One of the most famous cryptids is the Loch Ness Monster. Along with the Yeti and the Sasquatch, Nessie is one of the "Big 3" cryptids, i.e., the most famous cryptids.
Ever since it was first sighted, people have always wondered what the Loch Ness Monster might possibly be. The suggestions range, very drastically. On the one hand, we have the skeptics who say that the sightings are easily explained by pieces of driftwood, misidentifications of common animals, seiches, etc. On the other hand, we have the paranormal enthusiasts who say that the Monster might be a ghost, or an alien, or even a shape-shifter from the Delta Quadrant (yeah, I know I just made a Star Trek reference, but whatever). However, in this blog post, I am only going to discuss the theories that describe the Loch Ness Monster as being an actual animal.
Perhaps the most popular theory is that Nessie is a surviving Plesiosaur. Plesiosaurs were a group of marine reptiles, that lived during the Mesozoic Era. In 1933, in a newspaper report of a sighting, it was claimed that the Monster "bore a striking resemblence to the supposedly-extinct plesiosaur". Afterwards, this theory became, by far, the most popular explanation for the monster.
Another theory is that it is a giant eel. A quick examination of this theory, however, shows that it isn't very likely. This is because most sightings of the monster describe it as undulating its body, up and down, in order to swim. Meanwhile, eels swim from side-to-side, like most other fish.
Another hypothesis is that the monster is a species of gigantic, long-necked amphibian. Loch Ness Monster researcher R.T. Gould suggested that the monster could be something like a long-necked newt. In his 1976 book The Monsters of Loch Ness, Dr. Roy P. Mackal came to the conclusion that Nessie is most likely to be a surviving embolomer, which was a giant prehistoric amphibian, from the Carboniferous Period.
Perhaps the most likely candidate for the Loch Ness Monster, in my opinion, is an unknown species of long-necked, long-tailed pinniped. In 1892, in his book The Great Sea Serpent, the Dutch naturalist Anthonie Cornelis Oudemans first described a hypothetical new species of long-necked pinniped, in order to account for sightings of sea serpents, which he called Megophias megophias.
Therefore, I have now come to the conclusion that an unknown species of pinniped, similar to Oudemans's Megophias megophias, would be the best possible identity, for the Loch Ness Monster.
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In the future, I am going to write a few more posts, about Nessie and her kin, so hang in there! ;)
Ever since it was first sighted, people have always wondered what the Loch Ness Monster might possibly be. The suggestions range, very drastically. On the one hand, we have the skeptics who say that the sightings are easily explained by pieces of driftwood, misidentifications of common animals, seiches, etc. On the other hand, we have the paranormal enthusiasts who say that the Monster might be a ghost, or an alien, or even a shape-shifter from the Delta Quadrant (yeah, I know I just made a Star Trek reference, but whatever). However, in this blog post, I am only going to discuss the theories that describe the Loch Ness Monster as being an actual animal.
Perhaps the most popular theory is that Nessie is a surviving Plesiosaur. Plesiosaurs were a group of marine reptiles, that lived during the Mesozoic Era. In 1933, in a newspaper report of a sighting, it was claimed that the Monster "bore a striking resemblence to the supposedly-extinct plesiosaur". Afterwards, this theory became, by far, the most popular explanation for the monster.
Another theory is that it is a giant eel. A quick examination of this theory, however, shows that it isn't very likely. This is because most sightings of the monster describe it as undulating its body, up and down, in order to swim. Meanwhile, eels swim from side-to-side, like most other fish.
Another hypothesis is that the monster is a species of gigantic, long-necked amphibian. Loch Ness Monster researcher R.T. Gould suggested that the monster could be something like a long-necked newt. In his 1976 book The Monsters of Loch Ness, Dr. Roy P. Mackal came to the conclusion that Nessie is most likely to be a surviving embolomer, which was a giant prehistoric amphibian, from the Carboniferous Period.
Perhaps the most likely candidate for the Loch Ness Monster, in my opinion, is an unknown species of long-necked, long-tailed pinniped. In 1892, in his book The Great Sea Serpent, the Dutch naturalist Anthonie Cornelis Oudemans first described a hypothetical new species of long-necked pinniped, in order to account for sightings of sea serpents, which he called Megophias megophias.
Therefore, I have now come to the conclusion that an unknown species of pinniped, similar to Oudemans's Megophias megophias, would be the best possible identity, for the Loch Ness Monster.
---------------------------------
In the future, I am going to write a few more posts, about Nessie and her kin, so hang in there! ;)
Saturday, April 7, 2012
Fuzzy Tyrannosaurs!
The Chinese palaeontologist Xu Xing and colleagues recently described a very interesting new species of tyrannosauroid. The fossils were recovered from China's Yixian Formation, which dates from the early Aptian stage, of the Early Cretaceous Period. They named it Yutyrannus huali. It is the first tyrannosaur species described in 2012. It was classified as a basal member of the Tyrannosauroidea, being more derived than the likes of Dilong, Guanlong, and Sinotyrannus, but more basal than Eotyrannus. It was much larger than other basal tyrannosauroids, being about 9 meters (30 feet) long, and weighing up to 1,414 kilograms (3,120 pounds).
The most interesting aspect of this incredible creature, however, is not its size, but something completely different. Fossilized impressions of primitive feather-like structures were found around the fossil of the creature's body. The feathers were around 20 centimeters long, and they were filamentous. The feathers of Yutyrannus covered various parts of its body, including the pelvis, and the foot.
But, perhaps even more amazing is the fact that this newly-discovered dinosaur is a record-breaker; It is the largest known animal in history of which we have direct evidence that it had feathers. This record was previously held by the basal therizinosauroid Beipiaosaurus inexpectus, which was described in 1999.
This startling new find also has major implications, when it comes to how artists draw life reconstructions, of large tyrannosaurs. In my opinion, the discovery that Yutyrannus huali had feathers is a major piece of evidence that large, derived Late Cretaceous tyrannosaurids, such as Daspletosaurus torosus, Albertosaurus sarcophagus, Gorgosaurus libratus, Tarbosaurus bataar, and, yes, the infamous Tyrannosaurus rex, might have retained a feather coating, even as adults. However, as of now, all of this is just interesting speculation, and we have no way of knowing, for sure, if any of this stuff is true, or not.
However, one thing, we do know, for sure; The discovery of Yutyrannus proves that good ol' T. rex was actually much more similar to a chicken, than we had previously thought!
The most interesting aspect of this incredible creature, however, is not its size, but something completely different. Fossilized impressions of primitive feather-like structures were found around the fossil of the creature's body. The feathers were around 20 centimeters long, and they were filamentous. The feathers of Yutyrannus covered various parts of its body, including the pelvis, and the foot.
But, perhaps even more amazing is the fact that this newly-discovered dinosaur is a record-breaker; It is the largest known animal in history of which we have direct evidence that it had feathers. This record was previously held by the basal therizinosauroid Beipiaosaurus inexpectus, which was described in 1999.
This startling new find also has major implications, when it comes to how artists draw life reconstructions, of large tyrannosaurs. In my opinion, the discovery that Yutyrannus huali had feathers is a major piece of evidence that large, derived Late Cretaceous tyrannosaurids, such as Daspletosaurus torosus, Albertosaurus sarcophagus, Gorgosaurus libratus, Tarbosaurus bataar, and, yes, the infamous Tyrannosaurus rex, might have retained a feather coating, even as adults. However, as of now, all of this is just interesting speculation, and we have no way of knowing, for sure, if any of this stuff is true, or not.
However, one thing, we do know, for sure; The discovery of Yutyrannus proves that good ol' T. rex was actually much more similar to a chicken, than we had previously thought!
Wednesday, December 28, 2011
Dino Discoveries of 2011!
With the new year rapidly approaching, I will now take the time to reflect on what dinosaur discoveries were made during the year of 2011. The previous year, 2010, featured a plethora of new ceratopsian discoveries, including Utahceratops gettyi, Kosmoceratops richardsoni, and Vagaceratops irvinensis. Well, if 2010 was the Year of the Ceratopsian, then 2011 is the Year of the Troodontid! 3 new troodontids were discovered, this year: Xiaotingia zhengi, Linhevenator tani, and Talos sampsoni. This is more troodontid species disovered during a single year than in any other year in history, so far, ever since Troodon formosus was first described and named by Joseph Leidy, in 1856. Now, obviously, for Troodontid fans, like me, 2011 was a really awesome year!
Besides troodontids, several other dinosaurs have been discovered this year, including tyrannosaurids. Two tyrannosaurids have been found, this year: Teratophoneus curriei, and Zhuchengtyrannus magnus. Teratophoneus is significant, because it is one of the very few relatively well-preserved tyrannosaurids known from southern North America. It was described by Carr, Williamson, Britt, and Stadtman. It is classified in the tyrannosaur subfamily Tyrannosaurinae, which also includes the (in)famous Tyrannosaurus rex. It differs from other tyrannosaurids, in that it had a very short and deep skull, indicating that it presumably had a relatively strong bite force. Zhuchengtyrannus, on the other hand, was discovered in China. It is very closely related to Tarbosaruus bataar, sharing numerous features with it, especially in the skull and teeth. It was a very large predator, reaching lengths of up to 37 feet in length, and weights of up to 6 tons.
In addition to these, a new primitive theropod from the Triassic period has been discovered in South America. Its name is Eodromaeus murphi. It is believed to be one of the earliest known theropod dinosaurs, ever to have lived. It was described in 2011 by paleontologists Ricardo N. Martinez, and Jim Murphy.
Another newly-described dinosaur is Haya griva, an ornithopod, which was discovered in Mongolia. Several specimens were recovered, from 2002, to 2007. Haya is unique, in that one of the specimens preserves an enormous amount of smooth gastroliths, or "stomach stones", inside its rib cage. Although we are not yet completely sure, it is certainly possible that the animal had swallowed these stones, in order to aid it, in digestion.
And, finally, I am now going to talk about the troodontids. As I stated previously, three new troodontids have been discovered, in 2011. One of these is Xiaotingia. It was discovered in China, and described by Xu Xing and colleagues, in July 2011. Xiaotingia is very similar to Anchiornis huxleyi, another troodontid, discovered in 2009. Indeed, a cladistic analysis proved that it was actually the sister species of Anchiornis. However, perhaps what this dinosaur is most famous for is the controversy surrounding it. You see, in Xu's paper, he originally described Xiaotingia as being an archaeopterygid, rather than a troodontid. He then moved Anchiornis into the Archaeopterygidae, as well. He also re-classified the Archaeopterygidae as being deinonychosaurs, rather than primitive birds. This re-classification was very popular, in the media, with several articles online running headlines saying, "Archaeopteryx is no longer a bird!" and "Bird no longer: A prehistoric icon is knocked from its perch".
However, in early November 2011, another article by Lee and Worthy came out. Using the maximum likelihood phylogenetic assessment, they were able to figure out that Archaeopterygidae does, indeed, actually belong in the Avialiae, and not in the Deinonychosauria. In addition, the family was revised to include only Archaeopteryx and its close relative, Wellnhoferia. Thus, both Anchiornis and Xiaotingia were then taken back into the Troodontidae.
Xiaotingia was a very small troodontid, only about the size of a crow, or a raven. It preserves evidence of feathers on its body, just like numerous other small, feathered dinosaurs discovered in China.
The next troodontid is Linhevenator, which was officially described and named by Xing Xu and colleagues, in September 2011. Its remains were recovered from the Bayan Mandahu Formation, in Inner Mongolia, China. Linhevenator is unique, for several reasons. First of all, it is relatively rather large, for a troodontid, being slightly longer than the type specimen of Saurornithoides mongoliensis. Second of all, it displays a mixture of plesiomorphic and derived characteristics, which makes its exact phylogenetic placement somewhat difficult, to determine. However, the study managed to show that it was a more derived troodontid, in a polytomy formed by Troodon, and a clade containing Saurornithoides and Zanabazar.
Linhevenator also had large, dromaeosaurid-like sickle-claws, on its feet. These were much larger than those of more primitive troodontids, such as Sinovenator and Jinfengopteryx, indicating that derived troodontids converged with dromaeosaurids, in that they both developed rather large sickle-claws, on their back feet.
However, perhaps the most fascinating feature of Linhevenator was how it had very short arms. The arms of Linhevenator were very short, comparable in length to those of Austroraptor, or Compsognathus. It is currently unknown how, exactly, Linhevenator used its arms, although they might possibly have been used for digging, climbing, or help in mating displays.
The third troodontid described in 2011 is Talos, which was named and published by Lindsay Zanno and colleagues, just a couple of weeks after Linhevenator. It was very unique, for several reasons. First of all, it was discovered in the Kaiparowits Formation in Southern Utah. This makes it the very first troodontid besides Troodon that is known to have lived in North America, during the Late Cretaceous time period. This has very important implications, as the authors of the study noted, because it shows that the numerous remains assigned to Troodon are probably "overlumped", and that several species of Troodon, besides T. formosus, likely lived, in North America.
However, the most incredible characteristic of Talos is its great pathological value. The second toe on its foot, (the one bearing the deadly sickle-claw), was injured. Although we currently have no idea exactly what caused this injury, it must have been sustained either during prey capture, or in fights, with another member of the species.
Overall, 2011 was an awesome year, for dinosaurs! And, perhaps the most awesome thing about it, in my opinion, is how so many troodontids were discovered, during this past year. According to the Chinese Zodiac calendar, 2011 is officially the Year of the Rabbit. However, in my book, it is the Year of the Troodontid! Hmm…I wonder what 2012 is going to be? The Year of the Dromaeosaur? The Year of the Ornithopod? The Year of the Titanosaur? The Year of the Stegosaur? Well, I guess we will just have to wait and see!
Besides troodontids, several other dinosaurs have been discovered this year, including tyrannosaurids. Two tyrannosaurids have been found, this year: Teratophoneus curriei, and Zhuchengtyrannus magnus. Teratophoneus is significant, because it is one of the very few relatively well-preserved tyrannosaurids known from southern North America. It was described by Carr, Williamson, Britt, and Stadtman. It is classified in the tyrannosaur subfamily Tyrannosaurinae, which also includes the (in)famous Tyrannosaurus rex. It differs from other tyrannosaurids, in that it had a very short and deep skull, indicating that it presumably had a relatively strong bite force. Zhuchengtyrannus, on the other hand, was discovered in China. It is very closely related to Tarbosaruus bataar, sharing numerous features with it, especially in the skull and teeth. It was a very large predator, reaching lengths of up to 37 feet in length, and weights of up to 6 tons.
In addition to these, a new primitive theropod from the Triassic period has been discovered in South America. Its name is Eodromaeus murphi. It is believed to be one of the earliest known theropod dinosaurs, ever to have lived. It was described in 2011 by paleontologists Ricardo N. Martinez, and Jim Murphy.
Another newly-described dinosaur is Haya griva, an ornithopod, which was discovered in Mongolia. Several specimens were recovered, from 2002, to 2007. Haya is unique, in that one of the specimens preserves an enormous amount of smooth gastroliths, or "stomach stones", inside its rib cage. Although we are not yet completely sure, it is certainly possible that the animal had swallowed these stones, in order to aid it, in digestion.
And, finally, I am now going to talk about the troodontids. As I stated previously, three new troodontids have been discovered, in 2011. One of these is Xiaotingia. It was discovered in China, and described by Xu Xing and colleagues, in July 2011. Xiaotingia is very similar to Anchiornis huxleyi, another troodontid, discovered in 2009. Indeed, a cladistic analysis proved that it was actually the sister species of Anchiornis. However, perhaps what this dinosaur is most famous for is the controversy surrounding it. You see, in Xu's paper, he originally described Xiaotingia as being an archaeopterygid, rather than a troodontid. He then moved Anchiornis into the Archaeopterygidae, as well. He also re-classified the Archaeopterygidae as being deinonychosaurs, rather than primitive birds. This re-classification was very popular, in the media, with several articles online running headlines saying, "Archaeopteryx is no longer a bird!" and "Bird no longer: A prehistoric icon is knocked from its perch".
However, in early November 2011, another article by Lee and Worthy came out. Using the maximum likelihood phylogenetic assessment, they were able to figure out that Archaeopterygidae does, indeed, actually belong in the Avialiae, and not in the Deinonychosauria. In addition, the family was revised to include only Archaeopteryx and its close relative, Wellnhoferia. Thus, both Anchiornis and Xiaotingia were then taken back into the Troodontidae.
Xiaotingia was a very small troodontid, only about the size of a crow, or a raven. It preserves evidence of feathers on its body, just like numerous other small, feathered dinosaurs discovered in China.
The next troodontid is Linhevenator, which was officially described and named by Xing Xu and colleagues, in September 2011. Its remains were recovered from the Bayan Mandahu Formation, in Inner Mongolia, China. Linhevenator is unique, for several reasons. First of all, it is relatively rather large, for a troodontid, being slightly longer than the type specimen of Saurornithoides mongoliensis. Second of all, it displays a mixture of plesiomorphic and derived characteristics, which makes its exact phylogenetic placement somewhat difficult, to determine. However, the study managed to show that it was a more derived troodontid, in a polytomy formed by Troodon, and a clade containing Saurornithoides and Zanabazar.
Linhevenator also had large, dromaeosaurid-like sickle-claws, on its feet. These were much larger than those of more primitive troodontids, such as Sinovenator and Jinfengopteryx, indicating that derived troodontids converged with dromaeosaurids, in that they both developed rather large sickle-claws, on their back feet.
However, perhaps the most fascinating feature of Linhevenator was how it had very short arms. The arms of Linhevenator were very short, comparable in length to those of Austroraptor, or Compsognathus. It is currently unknown how, exactly, Linhevenator used its arms, although they might possibly have been used for digging, climbing, or help in mating displays.
The third troodontid described in 2011 is Talos, which was named and published by Lindsay Zanno and colleagues, just a couple of weeks after Linhevenator. It was very unique, for several reasons. First of all, it was discovered in the Kaiparowits Formation in Southern Utah. This makes it the very first troodontid besides Troodon that is known to have lived in North America, during the Late Cretaceous time period. This has very important implications, as the authors of the study noted, because it shows that the numerous remains assigned to Troodon are probably "overlumped", and that several species of Troodon, besides T. formosus, likely lived, in North America.
However, the most incredible characteristic of Talos is its great pathological value. The second toe on its foot, (the one bearing the deadly sickle-claw), was injured. Although we currently have no idea exactly what caused this injury, it must have been sustained either during prey capture, or in fights, with another member of the species.
Overall, 2011 was an awesome year, for dinosaurs! And, perhaps the most awesome thing about it, in my opinion, is how so many troodontids were discovered, during this past year. According to the Chinese Zodiac calendar, 2011 is officially the Year of the Rabbit. However, in my book, it is the Year of the Troodontid! Hmm…I wonder what 2012 is going to be? The Year of the Dromaeosaur? The Year of the Ornithopod? The Year of the Titanosaur? The Year of the Stegosaur? Well, I guess we will just have to wait and see!
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