Showing posts with label Teeth. Show all posts
Showing posts with label Teeth. Show all posts

Sunday, June 14, 2015

Jurassic World: Shed Teeth

At one point in the new Jurassic World movie, the main character Owen Grady (played by popular actor Andy Dwyer) pulls a broken tooth from the main monster Indominus rex from the shell of one of the Gyrospheres.  Believe it or not, broken teeth just like this are incredibly important for paleontologists when it comes to studying many different aspects of dinosaur habits and behavior!  First, let's take a quick look at the anatomy of a dinosaur tooth.
A pair of Tyranosaurus rex tooth casts with my camera lens for scale.
In the picture above, both teeth belong to the famed tyrant lizard king Robert California Tyrannosaurus rex itself!  The tooth on the top is larger, but it wouldn't have appeared that much larger in the mouth of the animal.  The reason behind that is the darker brown part on the left of the tooth is actually the root of the tooth, and would have been inside the animals skull.  The tooth underneath, the darker brown one, is a shed tooth crown.  Dinosaurs, unlike mammals, have an infinite supply of teeth, and if they lost a tooth it simply didn't matter!  They would grow another one in its place in a few weeks.
Stan, the Tyrannosaurus rex skull on display at the Morrison Natural History Museum.  Look on the upper jaw.  See the largest tooth, just about in the middle of the tooth row?  Let's zoom in and take an inside look! 
This is a view from the inside of the Tyrannosaurus skull from above, a view that the lawyer from Jurassic Park probably didn't find quite as fascinating.  See the largest tooth in the middle of the picture?  Notice how there's another little bump at the top of the tooth row, where the teeth are emerging from the maxilla bone.  That's actually another tooth growing in underneath!  If we CT scanned the original fossil, you'd be able to see all sorts of teeth growing in underneath!
Here we have a dental battery of the famous Triceratops, on display at the Rocky Mountain Dinosaur Resource Center (RMDRC) in Woodland Park, Colorado.  Now take a look at the picture below. 
Here, we have an individual tooth of Triceratops, out of the dental battery that you can see in the picture above.  This specimen is from the Hell Creek Formation of South Dakota, and also on display at the RMDRC.
The reconstructed jaws of the enormous, sixty foot long shark Megalodon, on display at the Mace Brown Museum of Natural History at the College of Charleston in South Carolina.  Like other sharks, as well as dinosaurs, you can see the several rows of teeth in the jaws of this guy, as well as the enormous biceps on the arms of the sexy Chris Pratt look-alike on the right.  Biceps for scale are approximately 36 inches in diameter.
Here and below, we have pictures of part of the dentary of the large carnivorous theropod dinosaur Torvosaurus from the Late Jurassic Morrison Formation.  You can see on the end in the picture above, the tooth is growing in, while the rest of the teeth are pretty well established.  This fossil is on display at the University of Colorado Museum of Natural History in Boulder
Another shot of that Torvosaurus dentary seen above, you can see another tooth growing in as well, second from the left.
Shed teeth can be quite important for paleontologists when it comes to determining behavior of these extinct creatures.  When paleontologists discover shed teeth of an animal, it can be a good indicator that the dinosaur was feeding on something nearby.  Unfortunately, shed teeth are easily recognized as fossils by most laymen, and are therefore often picked up by the public or fossil collectors looking to make a quick buck, thereby destroying any information we could potentially gain from such knowledge.  With good samples of shed teeth, like those employed by paleontologist Dr. Robert Bakker at the Late Jurassic Morrison Formation site of Como Bluff in Wyoming, scientists can learn about dinosaur diets, habits, habitats, and behavior, such as group movement, pack hunting, and even whether dinosaurs cared for their young!
A shed tooth crown of a Tyrannosaurus on display at the RMDRC.
Several shed phytosaur teeth on display at the Denver Museum of Nature and Science.  Phytosaurs were distant cousins of dinosaurs, and looked a lot like crocodilians.
A shed tooth of Nanotyrannus, a small cousin of Tyrannosaurus rex, from South Dakota.
Leidyosuchus, a type of Cretaceous crocodilian, with several shed teeth.
Brachychampsa, another Cretaceous crocodilian.
In 1877, local geologist Arthur Lakes discovered the very first bones of the dinosaurs Stegosaurus armatus and Apatosaurus ajax in Morrison, Colorado, and if you check out the Morrison Natural History Museum, you can actually see them there today!  Surrounding the genoholotype of Apatosaurus ajax, the very first specimen called YPM 1860, was reported by Lakes to have seven shed teeth belonging to an allosaur surrounding the specimen.  This indicates some that the predatory allosaurs were actually feeding on the Apatosaurus, which is very interesting information for paleontologists to have!  Below are two pictures of part of that YPM 1860 specimen, with the Director and Chief Curator of the Morrison Natural History Museum Matthew Mossbrucker pointing to the shed allosaur tooth crown.  These pictures are from the collections of the Yale Peabody Museum in Connecticut.
Shed allosaur tooth crown in the matrix of YPM 1860.  Photo Credit: Matthew Mossbrucker 
Shed allosaur tooth crown in the matrix of YPM 1860.  Photo Credit: Matthew Mossbrucker
Non mammals rarely have more than one type of tooth in their mouth, and when they do, it can often be the cause of celebration.  For example, in our previous post about the Latin and Greek root of two, we discussed two animals called Dimetrodon and Dimorphodon.  Dimetrodon is an early ancestor of modern mammals, and its name means "two measures of teeth," as it has two different types of teeth in its mouth.  Dimorphodon is a type of pterosaur (sometimes referred to as pterodactyls), a distant cousin of Pteranodon, whose name means "two morphs of teeth," again in reference to the fact that two types of teeth are in the animals mouth.  The animal below is a dinosaur called Heterodontosaurus, who belongs to the eponymously named family of dinosaurs, the Heterodontosauridae.  As you can see in the picture below, Heterodontosaurus has several larger teeth in the front of their mouth, and smaller teeth in the back.
Heterodontosaurus, a small little Early Jurassic dinosaur from South Africa.  As you can see, there are two different types of teeth in their mouth, larger ones in the front and smaller ones in the back.
One of the things that make mammals special is our teeth.  One of the most classic features of us mammals is our varied teeth.  In us humans, we have our incisors and canines in front, and our chewing molars in the back.  Since most mammals were only about the size of a shrew back during the Mesozoic Era, the time of the dinosaurs, in many places such as Como Bluff in Wyoming, paleontologists rely almost exclusively on the teeth of the tiny little mammals, since the teeth are much harder and more durable than the rest of the skeleton.  Below, we have a trio of elephantid molars on display at the Mace Brown Museum of Natural History at the College of Charleston in South Carolina.  Look at how varied the teeth are!  The first two belong to animals whose teeth were better adapted for crushing and grinding tougher vegetation, while the last molar would have been better for mashing up grasses.
Cuvieronius tropicus, a Pliocene-aged elephantid from South Carolina.  Large, high-cusped molars for crushing and grinding tougher vegetation.
Stegomastodon mirificus, a Pliocene and Pleistocene-aged elephantid, discovered in the Ashepoo River of South Carolina.  Like Cuvieronius, Stegomastodon also has those large, high-cusped molars that are great for demolishing tough plant matter.
The Imperial mammoth (Mammuthus imperator) from the Pleistocene of Florida.  These guys have a similar design of tooth to the dental battery of the ceratopsian dinosaurs mentioned above.  The duck-billed dinosaurs, or hadrosaurs, also had a similar design.  These teeth are broad and flat and good for mashing up grasses.
Shed teeth can be pretty important when paleontologists study fossils and extinct animals.  They are good at establishing behavior, and can be pretty important for long-term studies of paleoenvironments.  So when Owen uses the shed Indominus tooth in Jurassic World, believe it or not, that's actually something that paleontologists do from time to time!

Tuesday, January 7, 2014

The Shark-Like Edestus: An Interview With Wayne Itano

We've heard from Wayne Itano before, when he told us about the Kremmling Cretaceous Ammonite Locality in Colorado. (To read the post, click HERE.) A physicist at NIST (National Institute of Standards and Technology) in Boulder, Colorado, Wayne also has a hobby interest in paleontology, and is a curator adjoint at the Natural History Museum of the University of Colorado. He has also been doing some very interesting work with a shark-like animal called Edestus, and he graciously agreed to answer a few questions for me regarding this creature! So please join me in welcoming Wayne Itano, as he tell us about this fascinating prehistoric creature!
Scissor-tooth model for Edestus.  Credit Ray Trollwww.trollart.com
The Natural World:  You've been doing some work with an ancient shark-like creature called Edestus. What can you tell us about it?

Wayne Itano:  Edestus is my candidate for the strangest shark of all time. In my opinion, it is even stranger than the better-known spiral-toothed Helicoprion, since it is harder to imagine how the teeth might have been used.  (Read more about Helicoprion HERE.)  Almost the only fossil remains of Edestus are its symphyseal (midline) tooth whorls, which consist of triangular, serrated teeth, joined together at the bases (roots).

Edestus had one tooth whorl in the upper jaw and one in the lower jaw. Since the whorls are bilaterally symmetric (same on the left side as on the right side), they must have been located in the middle of the jaws.

This is a photograph of a specimen of a species called Edestus mirus. It was found in Pennsylvanian-aged deposits (about 300 million years old) of Iowa.
Smithsonian Institution Specimen USNM V 7255. Scale in cm.  To see a better resolution of the picture, click HERE.  Photo Credit: http://collections.si.edu/search/results.htm?view=&dsort=&date.slider=&q=Edestus+mirus+holotype&tag.cstype=all
This is a rare specimen, since it shows both the upper and lower tooth whorls.

The curvature of the tooth whorls makes it difficult to understand how they could have been used.

According to the conventional reconstruction, the two tooth whorls were used as scissors, to cut prey between the two whorls, as in this drawing by Ray Troll.
Scissor-tooth model for Edestus.  Credit Ray Troll, www.trollart.com
To me, this model seems unlikely, given the curvature of the tooth whorls. It seems that the outer teeth are nonfunctional, since they can’t come together, so there would be no reason to retain them.

It seems to me that the teeth would be more efficiently used if the entire head was moved up and down, with jaws fixed, to slash large prey. This is a radically new idea. I have submitted an article for publication elaborating on this idea, but I expect that it may be some time before it gets into print.
New vertical-slashing model for Edestus. Drawing by Gary Raham, www.biostration.com, reproduced with permission of Wayne Itano
My new reconstruction of Edestus, showing the pair of symphyseal tooth whorls, in front, used for slashing prey, and flat teeth in the rear for crushing prey. Drawing by Gary Raham, www.biostration.com, reproduced with permission of Wayne Itano.
TNW: I noticed that you referred to Edestus as being a candidate for the "strangest shark of all time." Is Edestus truly a shark? If not, how do you classify it?

WI: I was using "shark" in an informal sense, as the term is not well-defined for many extinct fish. Edestus certainly falls within the class Chondrichthyes, which today comprises 2 subclasses - Elasmobranchii (sharks, including rays) and Holocephali (ratfish). There is some evidence that Edestus (and also Helicoprion) belong to an extinct line that is closer to the Holocephali than to the Elasmobranchii, but this is a matter of debate. It is safe to call Edestus a chondrichthyan, and I try to avoid the word "shark" when I write a technical paper, or maybe keep it in quotes.

TNW:  Tell us a little bit about your research.

WI:  I am interested in many aspects of paleontology, but for the last 22 years I have focused on fossil sharks, particularly ones from the Paleozoic (older than about 250 million years ago). My interest in Paleozoic sharks dates from 1991, when I found a finspine of a Pennsylvanian-aged shark called Ctenacanthus in a roadcut near the town of McCoy, in Eagle County, Colorado. I wrote an article about this find for the newsletter of the Western Interior Paleontological Society (WIPS) in 1992, which you can read by clicking HERE.
Ctenacanthus finspine found near McCoy, Colorado. Scale in cm.  Photo Credit: Wayne Itano
In trying to identify this finspine, I read everything I could find about Paleozoic sharks. Knowing of my interest in the topic, Professor Martin Lockley of the University of Colorado at Denver loaned me a large collection of shark teeth and finspines from McCoy that he and Karen Houck, also of CU Denver, had found in the 1980s. His paleontological interests had by then switched entirely to ichnology (footprints and other fossil traces), and he gave me the opportunity to write up the fossil shark specimens. I published an article on the finspines in 2003 with Houck and Lockley, which you can read HERE, but I haven’t finished with the teeth yet.

My interest in Edestus started when an amateur fossil collector showed me an unusual shark tooth that he had found at McCoy. After a bit of study, I realized that it was a tooth of Edestus, the first known from the entire Rocky Mountain region. This eventually led to my publishing a rather long paper on Edestus in 2012, again with Houck and Lockley, which you can read HERE.

Recently, I have also published three short papers related to Edestus: one on an Edestus tooth from England, one on an Edestus tooth with abnormal serrations, and one on a tooth from China that had mistakenly been identified as Edestus, but which actually belonged to a more “normal” shark called Carcharopsis.

TNW:  Do you have any future expeditions or research papers in the works?

WI:  Lately most of my “field work” has been in museum collections. In the last few years I have been able to view specimens in the collections of the Yale Peabody Museum, the Natural History Museum (London), the British Geological Society, the American Museum of Natural History (New York), and the New Mexico Museum of Natural History and Science. I have several publications in the works, largely based on fossil shark specimens I have seen in those collections.

One area is the taxonomy (classification) of Edestus species. About 15 species of Edestus have been named, but I think that many of these are synonymous. For example, people have named new species based on unusually small or large teeth, but I think they are just teeth of the same species of Edestus but of different ages. There may be as few as 3 valid species of Edestus.

I have another project where I am examining microscopic scratches on Edestus teeth. I am hoping that I can find feeding-related scratches and that their orientation will provide some clues as to whether the scissors-model or the up-down-slashing model is correct.

-Thank you so much, Wayne, for answering some of my questions!  I look forward to hearing more about Edestus in the future!  Thanks again!-

Tuesday, August 13, 2013

The Truth Behind the "Truth" Behind Megalodon

Today, the great white shark rules the seas and haunts our imaginations.  After the release of the 1975 movie "Jaws," the great white shark and other sharks were feared and loathed more than they already were, although much of this fear was unbiased.  Ever since Jaws, hundreds of books, movies, television programs, and more have all capitalized on the shark craze, producing everything from the fantastic Steve Irwin Crocodile Hunter specials to the recent TV movie Sharknado.  One of the most popular shark-related features in the media is Discovery Channels "Shark Week," an annual event that features a week of shark-related programs.  Although many of these programs, as is to be expected for television programs nowadays, push the limits of reality, I think that the premiere of this year's Shark Week went too far, and I'm not the only one who thinks that, either.

First off, let's meet the star of this program: megalodon.  Estimates of the size of megalodon have varied widely and wildly, with some older estimates as high as about 100 feet long.  Today, however, most scientists agree that the largest megalodon could grow to around 60 feet long.  Which is still pretty massive, given that most great white sharks don't exceed lengths of around 20 feet, and look at how much people are afraid of them!  megalodon would have easily been able to swallow the average human in one bite: just take a look at those reconstructed jaws, below!  Also, below that picture, make sure to check out the size of just one megalodon tooth.  Suffice it to say, this shark was one massive bruiser.  This shark WAS one massive bruiser.  Notice how I emphasized the "was?"  Well, that's because megalodon went extinct about two million years ago.
Pyg encounters a mid-sized megalodon tooth, graciously donated to my collection of fossils and things that I take to local schools by local paleontologist Wayne Itano
Megalodon sounds pretty awesome, right?  I mean, to be honest, it's one of those extinct animals that just doesn't need to be "sci-fied up," because it's already cool enough as is, on par with other animals such as Tyrannosaurus, Spinosaurus, and Utahraptor.  Well, just because it didn't NEED to be sci-fied up doesn't mean that television networks didn't do it anyways.  And this years Shark Week premiere was the culprit.  Discovery Channel aired a two hour "documentary" showing "biologists" on the hunt for a megalodon.  Today.  In the present.
One of those extinct animals that just doesn't need to be "Hollywoodized!"  Meet Stan, the resident Tyrannosaurus rex at the Morrison Natural History Museum!  You can see Pig seated in the bottom jaw for scale!  Yeah, this guy was huge.
We have no evidence to indicate that megalodon is alive and with us today, and the "evidence" included in the "documentary" was very clearly doctored.  For example, below is a picture of a whale that has supposedly been bitten in half by a megalodon:

And here is a photo "uncovered from Nazi archives" of a giant shark fin surfacing behind a pair of U-Boats:

The first picture just screams CG.  And the second one....really?  Nazi's? Very Indiana Jones-esque.  OK then, Discovery.

The "documentary" starts off with "found footage" of a "boat capsizing off the coast of South Africa and several people being eaten, but whose bodies were never recovered."  Already, this reeks of a typical television plot.  Especially given the fact that a quick Google search of this supposed incident, as well as any of the "biologists" in the "documentary," yields diddly-squat.  Apparently the prospect of a giant shark brutally attacking and destroying a fishing boat just wasn't exciting enough to make it to the news, despite the fact that every news story relating to sharks and shark attacks spreads like wildfire.  Perhaps the South African press was just busy that day?

People refute our naysaying by pointing out that "we know more about the surface of the moon than the ocean," and "the coelacanth (which you can learn more about by clicking HERE) and the giant squid were only discovered recently!"  Yeah, that's true.  But megalodon is very different from a giant cephalopod or a five or six foot long fish.  We are talking about an active, 60 foot long predator that's feeding on much, much bigger prey than the giant squid or coelacanth would.  The giant squid and coelacanth eat a lot of fish, and are considered to be primarily piscivorous.  The giant squid, although very large, is by no means at the top of its food chain, and is fed upon by the largest of the toothed whales, the 60 to 70 foot long sperm whale.  And two million years ago, megalodon would have made up the final link in this food chain, feeding on the 60 to 70 foot long sperm whale.

Am I saying that there is no possibility that more giant animals exist in the deepest depths of the ocean, just waiting to be discovered?  No, I most definitely am not.  I do, however, encourage you to consider the ecological resources that would be needed by such a massive animal.  With no evidence of mutilated whale carcasses that could be attributed to such a massive animal, and an equal amount of evidence from first-hand accounts....I think that the conclusion should speak for itself.

The biggest issue that I have with all of this is not that a television program was made that packages myths, untruths, and exaggerations: it was with the fact that they packaged it as a documentary, no quotations this time.  Discovery tried to balance out the fact that they blatantly made stuff up to appease some of their viewers by pointing out that they included disclaimers in the show.  Yeah, true, there were disclaimers: but click HERE to see how short and hazy these disclaimers really were.  The disclaimers read:

None of the institutions or agencies that appear in the film are affiliated with it in any way, nor have approved its contents. Though certain events and characters in this film have been dramatized, sightings of "Submarine" continue to this day. Megalodon was a real shark. Legends of giant sharks persist all over the world. There is still debate about what they might be.

Notice how they never really say that none of it was true.  When he gave a press release, the executive producer of Shark Week, Michael Sorensen, said that “With a whole week of Shark Week programming ahead of us, we wanted to explore the possibilities of megalodon.  It’s one of the most debated shark discussions of all time, can megalodon exist today? It’s Ultimate Shark Week fantasy. The stories have been out there for years and with 95 percent of the ocean unexplored, who really knows?”  The part that bugs me the very, very most about that statement is the line "It's one of the most debated shark discussions of all time."  It isn't, I promise you.  It really, really isn't.  I have never heard of any paleontologist who seriously believes that megalodon swims the oceans today.  There might be some paleontologists who won't discount the possibility, which is fine.  Science changes all the time.  But with a complete and total lack of evidence, no serious scientist will really debate that sort of thing.

There's many more issues that people have had with this presentation, varying from thousands of people on social media voicing their complaints, all the way to actor Wil Wheaton, who wrote about the megalodon fiasco on his blog, which you can read HERE.  Others, such as popular paleo writer Brian Switek, went to Twitter:

I do hope that this backlash will cause the people at Discovery, as well as at other television stations, to reconsider what they make into a television program, and consider the possibility that, just maybe, there's a significant chunk of people out there who don't want to be fed this garbage.  I do hope that this causes some changes in any future programming, and if we are all really lucky, this event might spawn a South Park episode.  You have to admit, it'd be pretty perfect.  Let's just cross our fingers, shall we?

Wednesday, July 10, 2013

A New Hairdo for the Alpacas: An Article from the Wild Animal Sanctuary

Remember that post I did a few weeks back about the giant bears I saw at the Wild Animal Sanctuary in Colorado?  (If not, you can just click HERE to catch up).  Anyways, I thought it might be interesting to see if anyone at the sanctuary would be willing to do a guest post on the blog!  The person I corresponded with, however, said that all of the staff members are putting in 60-70 hours per week, and therefore are absolutely unavailable!  My correspondent did say that I could feel free to reprint some of the stories from the newsletters, and I thought that was a great idea!  In their last newsletter, they printed a story called "Summer's Here and It's Time for a New Hairdo," an article all about their fleet of shaved alpacas!  Since I thought these guys were totally awesome, I decided to reprint this story, as it is both interesting, educational, and really, really funny!  So please, enjoy, and make sure to check out the Wild Animal Sanctuary, and like their Facebook page by clicking HERE!  Also, be sure to check out their website by clicking HERE!  

It seems like everyone likes to observe the seasonal changes with some sort of personal change in their own life. It’s possible they are trying to mirror the change in landscape… or more likely, they’re trying to find a balance with nature. Sometimes this sort of thing can come in the form of a new wardrobe… and others might find balance by including more outdoor activities to get them in the groove.


Yet, whatever you like to do when the weather and daylight start to shift… there’s always one thing that pops up on an Alpaca’s springtime dance card – a trim and shave! Yep, that’s right, there’s nothing more refreshing than a late spring haircut to lift the spirits of an Alpaca - especially since wearing a winter coat in July or August can get a bit stuffy!

With this in mind, we started late last year trying to find a viable solution to our shearing needs for the 50+ Alpacas that live at the Sanctuary. Mind you, shearing one or two wouldn’t be so bad… but when you are looking at more than 200 fuzzy legs that happen to have big fuzzy bodies attached to them – one has to be realistic when it comes to planning how to get the shearing job done!

Luckily, through a myriad of connections talking with each other, we were able to find an Alpaca Ranch in Montana that routinely hires a professional shearer each spring to help lighten the load of their Alpacas. The Ranch owners offered to help the Sanctuary by paying for their shearer to come to the Sanctuary – along with the ranch’s own special team of Alpaca wranglers – in order to shear all of our Alpacas in the spring.

They were happy to share their expertise in the art of Alpaca wool management, and planned on taking the wool back to Montana to turn it into highdollar rugs. They then planned on sending some of the rugs down to us to sell in our gift shop… as well as retail the rest to clients that have been following their wool artistry for many years.

Well, April finally rolled around, and the out-of-state shearing party arrived as scheduled. However, the Sanctuary’s staff ended up having to jump in the middle of the Alpaca wrangling end of things when the ranch’s wranglers came up missing.

Actually, it turned out to be a good adaptation, since we were happy to participate in order to ensure our Alpaca’s visit with the barber turned out to be a positive one. Besides, they’re all so cute that it’s a pleasure to spend time amongst this curious flock!

We started early in the morning and worked with precision. We were able to have two areas where the Alpacas would be laid down to get shaved. As one would be getting his or her hair clipped… the other would be getting his or her hooves trimmed and teeth checked. 

The shearer spent the day swapping back and forth while the ranch owners and Sanctuary staff took care of all the oddities like wool collection and doing discretionary medical exams.

We ended up with some pretty slick-looking Alpacas… and they ended up feeling substantially lighter. Their final appearance was definitely charming, as most of them ended up looking more like “Pokey” – “Gumby’s” sidekick of a horse!

When it was all over, the ranchers were forced to spend some time trying to pack 50+ Alpaca’s worth of wool into a regular-sized Chevy van (which ended up being packed solid, floor to roof), while our dainty-looking heard of Alpacas trotted off into the sunset. It’s definitely a new season, and the Alpacas definitely have a new hairdo, so as far as we’re concerned… it feels like everything is in balance again! 

Did you like what you just read?  Well, make sure to check out the Wild Animal Sanctuary's newsletter page by clicking HERE!  Make sure to also like their Facebook page by clicking HERE, and to check out their website by clicking HERE!  

Monday, December 10, 2012

23-Fact Tuesdays: Polar Bear Celebrations, Eccentric Artists, and Unicorn Horns!

Welcome to our third "23-Fact Tuesday" which are never on Tuesdays.  I believe that this one is actually closer to a Tuesday than we ever have been before, however, so that's got to count for something!  I'd also like to thank Mona Kamath for her help on this post!  Enjoy!

1.  Despite the fact that polar bears are generally solitary, they gather annually in places like the city of Churchill in Manitoba, Canada, where they congregate together prior to the freezing of the sea ice.  When they gather in groups like this, the group is called a "Celebration." 

2.  The eccentric and incredibly odd (though undeniably gifted) artist Salvador Dalí had a pet ocelot named Babou.  He also had a pretty righteous mustache, if I do say so myself.

3.  In 1663, the German scientist Otto von Guericke "reconstructed" the mythical unicorn using the fossilized bones of a mammoth, a woolly rhinoceros, and the horn of a narwhal.  This reconstruction managed to legitimately fool some people, including Gottfriend Wilhelm Leibniz, the famous German philosopher and mathematician, who reportedly was dubious about the existence of the unicorn prior to this "reconstruction," but was convinced by Guericke's "fossil."  

4.  From wing tip to wing tip, Hatzegopteryx measured an astonishing 46 feet!

5.  Gasosaurus, a dinosaur that was described in the year 1985, was named "Gas-Lizard" because it was discovered by a Chinese gas-mining company.

6.  In order to hover and move in any direction, the hummingbird, often nick-named "nature's helicopter" moves its wings in a figure-eight pattern, as opposed to the up-and-down motion typical of other birds.

7.  Cotylorhynchus, one of the largest pelycosaurs, is quite possibly the funniest-looking extinct animal I have ever, ever seen.  It was also discovered by my 9th grade Language Arts teacher's great great uncle, J. Willis Stovall, a famous paleontologist

8.  One of the elephants at the Cheyenne Mountain Zoo is named Kimba, which means "Poop" (I used the nicer term for what the word actually means there) or "Corpse" in Swahili.

9.  Speaking of poop, fossil poop is known as a "coprolite."

10.  The acrobatic margay can rotate its ankles 180 degrees, which allows it to descend tree trunks head-first and hold on to branches with either their front or back paws.

11.  The white-tailed deer is named for the white patch on its rump and tail, while the mule deer is named for the fact that its face resembles that of a mules.

12.  About a third of the extant mammalian species are rodents.

13.  Hopping, the method of locomotion preferred by the kangaroos, is actually much more efficient than walking.  Of course, this is only the case if you have evolved in that fashion.  It wouldn't just be more energy efficient if we started hopping around everywhere.  

14.  Although you often hear people mention the "saber-toothed tigers," this is actually a bit of a misnomer, due to the fact that the saber-toothed cats to which they are referring to are not actually tigers, and are simply just cats.  

15.  The sweat of the Hippopotamus, is red or pink, leading people to aptly refer to it as "blood-sweat."

16.  Despite the fact that the polar bear has white fur, the color of its skin is the complete opposite: jet-black.  Talk about Yin/Yang right there.

17.  Island dwarfism is suspected to have occurred in one of our human relatives, Homo floresiensis, who inhabited the island of Flores in Indonesia up until around 12,000 years ago.  The nick-name for this ancient human is "The Hobbit." 

18.  The word "Mona" means "monkey" in Spanish.  Sure would suck if that was your name now wouldn't it!

19.  In Hindu culture, owls are a sign of bad luck.  That double sucks if you are Hindi and terrified of birds.

20.  Speaking of owls, due to the fact that they have binocular, or stereoscopic, vision (unlike other birds of prey, who have an eye on each side of its head), they have evolved the ability to turn their heads around 270 degrees in either direction.  Must be tough for them to crack their necks.

21.  Despite the fact that the creature in the picture below looks like a raccoon, it is not: that, my friends, is the raccoon dog!

22.  The tusks of the elephants are actually greatly elongated incisor teeth.  For reference, tap your front two teeth on the top or bottom of your mouth, it doesn't matter which, they are the same.  Those are your incisor teeth, you have two on each side of your mouth, eight all together.  

23.  In the narwhal, however, the tusk is their canine teeth, which (at least in our mouths) are the teeth right next to our incisors, towards the outside of our mouths. 

Top 10 Favorite Dinosaurs by Zack Neher (Part 3)

Part three of my Top Ten Favorite Dinosaurs list.  Enjoy!

3. Masiakasaurus
A fairly small dinosaur at only around six feet, Masakisaurus knopfleri, as discussed IN A PREVIOUS POST, was named for the famous musician Mark Knopfler.  The animal, found in Madagascar, was named in 2001 by Matthew Carrano, Catherine A. Forster, and Scott Sampson, the author of Dinosaur Odyssey and the dude from Dinosaur Train.  Living on what was still an island, the little dinosaur lived about 70 MYA during the  Late Cretaceous Period, and was a contemoporary of the abelisaur Majungasaurus, the bird-like Rahonavis, and the sauropod Rapetosaurus.  Although Masiakasaurus sounds pretty unremarkable thus far, a quick glance at the picture below (which many of you have no doubt already done) says otherwise: Masiakasaurus definitely had some funky teeth!  These teeth are clearly not suited tearing into food like the teeth of Allosaurus or Velociraptor would be, and many paleontologists (including myself, even though I am not really a paleontologist.  I guess it would be better to say "many paleontologists, paleontologists-in-training, and myself."  There, much better.) believe that these weird, pointy teeth are an evolutionary adaptation to a piscivorous (fish-based) diet.  A look at various marine reptiles such as the plesiosaurs (like Elasmosaurus) and Liopleurodon show a similar pattern of interlocking teeth that point outside of the mouth.  Excellent when it comes to catching fish, and not so excellent when it comes to most, if not all, other diets, be they meat- or plant-based.  

TO BE CONTINUED IN PART 4

Wednesday, August 1, 2012

What Is It? The Weekly Challenge #4 Answer

This weeks challenge was to figure out which, in the picture below, was a mammoth, and which was a mastodon. This weeks challenge was correctly guessed by two people, both Ilyssa A. and Masaki K., who both said mammoth on the left and mastodon on the right.  However, how can you differentiate between the two?  Obvious, we have two super-sleuth paleontologists on our hands who can differentiate, but I'm guessing that the vast majority of you might have trouble.  So here is a quick Mammoth Vs. Mastodon Guide, with just a few helpful ways to differentiate between the two.
A size comparison of a mammoth and a human, myself, at the excellent zoo called The Living Desert in California.  Photo Credit: Julie Neher
Check in a few hours for this weeks challenge!

Wednesday, July 4, 2012

The Biggest Carnivorous Dinosaur Part 3: Spinosaurus, The World's Largest Penguin

Spinosaurus quickly smashed its way to the top (literally!) following the success of Jurassic Park III.  At up to 56 feet (17 meters) in length, Spinosaurus (found in Egypt and Morocco) is unquestionably the longest carnivorous dinosaur that has ever been discovered, and by a significant margin, too.  But how could Spinosaurus be so successful when another carnivorous monstrosity, Carcharodontosaurus, lived in such close proximity?  The answer lies in what it ate; in fact, Spinosaurus appears not to have been as carnivorous as we once thought, and seems to in fact have been more piscivorous.  Essentially, it is thought that Spinosaurus might have survived on a diet consisting a great deal upon fish.

There is a great wealth of information that indicates the staple diet of Spinosaurus was fish.  Here we will take a more in-depth look at this evidence.
A picture of Spinosaurus drawn by the talented young artist Sam Lippincott.
1.  POSITION OF THE NOSTRILS:  Spinosaurus, unlike most other theropod (meat-eating) dinosaurs had nostrils situated very high up on its skull.  By contrast, most other theropods, like Tyrannosaurus, had nostrils very close to the front of the skull.  The nostril placement in Spinosaurus would have allowed it to stick its nose into the water quite deep, enabling it to hunt fish more effectively.

2.  SENSORY ORGANS ON THE TIP OF THE SNOUT:  Along with the high placement of the nostrils, Spinosaurus also had a number of small sensory organs at the front of the snout, revealed by CT scans.  These greatly resemble those of the crocodile, who uses them to sense where prey is by "seeing" tiny movements in the water.  Thus, a crocodile can attack its prey without ever seeing them with their eyes.  Spinosaurus appears to have been able to do much the same thing, making its hunting method of choice quite obviously effective, given its immense size.

3.  ISOTOPIC EVIDENCE:  A study of the isotopes in the skull of a Spinosaurus specimen revealed something quite interesting.  Spinosaurus shares a great deal of isotopic overlap with crocodiles, fairly aquatic animals.  By contrast, other carnivorous dinosaurs like Tyrannosaurus have very different isotopic readings, indicating a terrestrial lifestyle.  Given the great deal of overlap possessed by Spinosaurus and crocodiles, it appears that Spinosaurus spent much of its life like a crocodile; semi-submerged in rivers and streams.

4.  THE TEETH TELL THE TALE:  Spinosaurus, unlike most other carnivorous dinosaurs like Tyrannosaurus, Allosaurus, or the famous Velociraptorpossess conical, round teeth.  These other carnivores possess thin, blade-like teeth, made for slicing, crushing or tearing into other animals.  Spinosaurus has teeth much like a crocodile; round and conical.  These teeth are made for gripping and making sure that an animal does not escape. 

5.  THE TEETH TELL THE TALE....AGAIN:  Yet again, we come to the issue of teeth, and this is one of the most damning pieces of evidence of all.  During the time that Spinosaurus lived in North Africa, another inhabitant of these streams and rivers was a saw-toothed fish called Onchopristis.  Two fossils involving Onchopristis have been discovered in conjunction with the remains of Spinosaurus.  One was the skull of a Spinosaurus; imbedded in one of the tooth sockets was a vertebrae from an Onchopristis.  The other discovery was the barb of an Onchopristis embedded in the jaw of the Spinosaurus.

6.  PLUS:  We only ever seem to find Spinosaurus in shallow aquatic environments, where fishy prey would be abundant.

All in all, it seems like an inevitable conclusion to draw that Spinosaurus was, in fact, a piscivore, at least much of the time.  A fascinating example of the crazy turns evolution can take.
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