Thorny Trees and 20 Inch Tongues: A Case of Coevolution

A few days ago, I saw a very spiky-looking tree on the Bird of Prey Route near my house.  A few weeks ago, I saw another tree, much larger than this one, along the banks of Boulder Creek that had some enormous thorns on its branches as well, some of them easily six inches long, and super sharp on the end!  I don't know for certain what kind of tree this, or the Boulder Creek tree, is, but a good candidate I think is the honey locust (Gleditsia triacanthos), or some other tree closely related to the honey locust.  Below is the picture of the tree that I took on the Bird of Prey Route.

And here is the picture that I took on my iPhone at Boulder Creek of this tree.  The thorns look pretty similar to those of the honey locust, and I think that the trunk of the tree looks pretty similar, too.

Now why do these trees have such huge thorns?  When it comes to nature, everything evolves with a purpose.  There is no reason why a living organism would evolve something without a purpose, especially something as involved as giant, six-inch long thorns.  The question is, what purpose do these thorns serve?  Well that's a darn good question, and I am very pleased you asked.  Much like the "thorns" that you can see on the tail of a Stegosaurus, they likely were to help keep the organism from being consumed.  We see similar thorns on the branches of some trees in the genus Acacia in Africa today.  There, the thorns help protect the tree from attacks from one of the largest plant predators alive today, the giraffe.  This tree....well, suffice it to say that you probably won't see many activists hugging this tree.

"Oh, maybe these thorns look deceptively big," you're thinking.  Wrong.  These thorns do not look deceptively big.  If anything, they look deceptively small.  These thorns are frickin' HUGE.

So the real question is, why the long thorns, Goldilocks?  Many paleontologists believe that, during the Pleistocene Epoch (which lasted from between around 2.5 MYA to about 12,000 years ago), many of North America's mega-herbivores, everything ranging from mammoths and mastodons, to giant ground sloths and the North American camel Camelops, could have been preying upon these trees.  Selective pressures slowly caused these trees to evolve protection against these mammalian mega-herbivores.  Mastodons especially had very robust teeth, which would almost certainly have made them excellent bark-munchers.

In Africa, the acacia tree, also known as the whistling thorn, the thorntree, or (my personal favorite) the wattle, has a very similar defense.  Unlike the honey locust of North America, however, the acacia tree still has to deal with intense predation today, and from a wide variety of herbivores, everything from gerenuk to giraffe, elephants to more giraffes.

You see, the giraffes love the acacia tree.  If giraffes had Facebook, then they all would like the "I <3 Acacia Trees" page.  I remember reading somewhere that they can eat up to 60 or 65 pounds of acacia leaves per day.  (To understand this, try imagining a large hunk of butter that weighs 60 or 65 pounds.  Now you have an idea of how many pounds that is.)  They love it so much that, if the acacia tree hadn't adapted to keep up with the continual browsing pressure, the giraffes might have loved the acacia trees to death!  In response, the acacia trees convergently evolved these sharp thorns, just like the honey locust tree in North America.  (We talk about convergent evolution quite a lot as it is one of my favorite topics, so click HERE to learn more about it!)  

The giraffes love the acacia, though.  They aren't going to give up on those lovely leaves, just like that!  So while these acacia trees evolved their thorns to protect their leaves, the giraffes evolved something spectacular: a prehensile tongue!  Don't believe me?  Well, one of my favorite things about the Cheyenne Mountain Zoo is that you can feed the giraffes there.  And guess what: their tongues are HUGE!  Below, I have a video of my good friend Masaki Kleinkopf also feeding the giraffes!  Check out my gangsta hoodie, yo.  

So, yeah.  Suffice it to say, giraffes have frickin' long tongues.  And they use these TWENTY INCH LONG TONGUES to help circumnavigate through the acacia tree's poky and spiny maze of thorns to reach the leaves!  The acacia tree wasn't going to just take this lying down, though: no giraffe is going to be feeding on my leaves, yo!  So the acacia tree adapted again.  This time, by employing the use of tannins.

Long story short, tannins are used by humans in a variety of ways, including tanning, food processing, and making cocoa and wine.  They also apparently taste terrible.  Don't ask me, I've never tried it, but then again I don't have a 20 inch prehensile tongue, so it's a whole different ballgame.*

Not only do tannins taste terrible, but they inhibit the digestion of the leaf matter in a number of nasty ways, none of which would be all that fun for the giraffe.  So when a giraffe starts munching on the leaves of the acacia tree, that tree will release tannins to make the leaves taste like....well, leather I suppose.  (Again, haven't tried either.)  This tannin releasing is a pretty cool adaptation all on its lonseome.  The giraffe begins to move off to another acacia tree nearby.  However, if it's within 50 yards or so (especially downwind) of the original, now tanniny acacia, then the giraffe is out of luck: the nearby acacias react in turn, releasing their own tannins, and rendering their leaves almost indigestible to the giraffes, as well!  I would imagine that, because of this, giraffes have in turn developed the behavior of moving upwind as they eat, and a cursory glance over the Internet indicates that this does seem to be a behavior observed in giraffes!  Coevolution at its finest!

Make sure to check back soon for our next episode in our coevolution series, all about a very fun little squirrel!  See you then!  In the meantime, you can read about what coevolution actually is, by clicking HERE.

*The second baseball metaphor that I believe has been used on this blog.  Refer to "23-Fact Tuesday: Prairie Falcon, Red-Tailed Hawk, and Great-Horned Owl at the Dino Hotel" and "Eye Black: What Works for Football Players Works for the Cheetah" to learn more about this sport.  

Works Cited:

The New World Vultures: Top Ten Vultures (Part 2)

On Thursday, I published the first of our two-parter "Top Ten Vultures" posts, all in honor of International Vulture Awareness Day!  (Learn more HERE.)  In the last post, we looked at only the Old World Vultures, a group of birds that are native to Asia, Africa, and Europe.  Today, we will be looking at the New World Vultures who, despite their name, are not actually very closely related to the Old World Vultures at all!  Instead, the similarities in body design between the two different groups is a result of one of my favorite topics of all time, convergent evolution!  So let's do it: the last five of the top ten!  Meet my favorite five New World Vultures!  (For the previous post in the Top Ten Vultures duology, click HERE.)

5.  Number five on the list is the turkey vulture, a classic vulture for us Coloradans!  The only vulture alive today in Colorado (I suppose the occasional black vulture may wander in from the south), the turkey vulture is what many people think of when they hear the word "vulture."  I have noticed a lot (thirty or more) of turkey vultures circling this one place on the CU Boulder campus, so I am planning a little excursion to figure out what it is that is drawing them to that particular spot in such large numbers!  Recently, the folks at the Raptor Education Foundation brought a turkey vulture in to the Best Western Denver Southwest, a fun hotel that is currently undergoing renovations to become a functioning natural history museum!  (REF website HERE, BWDS website HERE.)  So here are some awesome pictures from that event!  If you guys ever get a chance to check out one of the presentations given by the folks at the Raptor Education Foundation, you definitely should go, it is a REAL treat!  In the pictures below, you can see the curator of the foundation, Anne Price, holding the turkey vulture, while the director, Peter Reshetniak (background), tells us a great deal about the bird!

4.  With nearly a ten foot wingspan, the California condor is the largest flying bird in North America!  (If you're having trouble visualizing ten feet, either go purchase ten one-foot long rulers and lay them end to end or, more simply, go find a good-sized California condor and stretch out its wings.  That's probably the best visual right there.)  The California condor is unfortunately labeled "Critically Endangered" by the IUCN, and it has experienced a pretty good comeback, and hopefully will continue to do so well into the future!  According to the IUCN website, the last six remaining wild individuals were brought into captivity for captive breeding purposes, making the species "Extinct in the Wild."  However, due to intense involvement from scientists, the species is on the rise, with around 213 individuals in the wild!

3.  Meet the only fossil vulture on our Top Ten list, Phasmagyps!  Some paleontologists are unsure whether Phasmagyps is actually a vulture, and this uncertainty is definitely understandable, as Phasmagyps is known from but a single bone!  If it is a vulture, then Phasmagyps might be the oldest known New World vulture!  Discovered in a Colorado quarry containing a number of fossils belonging to a 35 million year old rhinoceros called Trigonias, this single bone is now housed in the collections facility of the University of Colorado Boulder!  I'm not really sure what I'm doing yet, but I've tried to input a request to check out the bone, we'll see how that goes!

2.  Meet the Andean condor, one of the largest flying birds alive today, with more than a ten foot wingspan!  With an incredible lifespan of over 75 years in captivity, the Andean condor, much like most animals that live for a very long time, does not reproduce very quickly: and therein lies its vulnerability.  If, say, half of the population of Andean condors was shot in one year by humans, then it would take much longer for the population density to regain its former glory.  By contrast, if you destroy half of the population of, say, rats, then they would almost certainly regain their former numbers very quickly, as they reproduce at an alarmingly fast rate.  (The same principle applies to the California condor, who we talked about above.)  Fortunately, the Andean condor is nowhere near as vulnerable to extinction as its close relative, the California condor.

1.  At last, we come to my most favorite vulture of all time: the king vulture!  This guy is absolutely ridiculous looking, resembling a cross between a vulture, a turkey, and who knows what else!  It also has a very fun scientific name: Sarcoramphus papa!  Don't exactly know what it means, but I like to think it has something to do with being the Vulture Daddy.  I found on some sources online that the blood and feathers of the king vulture were used by the ancient Mayans to help cure disease, but I couldn't find any more information on that: all I found was the exact same sentence copied over and over again: "The bird's blood and feathers were also used to cure diseases."  An enigmatic sentence for a very engimatic looking bird.  But let's face it: it just looks awesome.

Thanks again for joining us today!  I do hope I have made you more aware of vultures of an international level!  But seriously, check out their page: http://www.vultureday.org/2013/index.php

The Old World Vultures: Top Ten Vultures (Part 1)

This coming Saturday is International Vulture Awareness Day, and in honor of the event, we are going to be taking a "Top Ten" look at the vultures!  Before we dive right in, I must make an important distinction.  Despite the fact that both the Cape Griffon vulture (native to Africa) and the turkey vulture (native to North America) are called vultures, they don't all belong to the same group!  Despite the often startling similarities possessed by these two different avian families, these similarities are not the result of a common ancestor, but the result of convergent evolution!  The Old World Vultures (native to Asia, Africa, and Europe) are in the same group of birds as the hawks and eagles do.  Meanwhile, the New World Vultures (native to the Americas) are just kinda out there, not too closely related to the Old World Vultures, but still birds of prey.  In order to keep this post from rapidly getting out of control (as has been known to happen to my blog posts), I have decided to break this Top Ten list into two parts.  The first part focuses on five awesome Old World Vultures, while the second post lists the last five vultures on the Top Ten list, all five of whom are New World Vultures!  Happy International Vulture Awareness Day, everybody!

10.  We'll start off with the lammergeier!  I remembered this one from a David Attenborough special that I saw several years ago!  This particular Old World Vulture was featured in a brief segment of "The Living Planet," and it was smashing good fun!  (That was a pun.  Unless you display a higher than average familiarity with your Old World Vultures, you probably won't get it.  But you will).  The lammergeier enjoys a nice meal of animal bones, especially the marrow on the insides, but oftentimes these bones are simply too tough for the bird to crack.  To successfully reach the innards, the lammergeier launches itself into the air, bone in hand, and flies upwards.  Once it has reached a satisfying height, the lammergeier will release the bone and, if all goes well, the bone will crack open upon impact with the hard rock below!  To see a video of this fantastic bird in action, make sure to click the link HERE!

2.  The smallest of the Old World Vultures, the palm-nut vulture is definitely quite distinctive, and, at least to my eye, looks a lot like an eagle!  (Not so much in the picture below, though, there it just looks like a bat!)  The palm-nut vulture, unlike most birds of prey, regularly consumes vegetable matter, with the primary component of its diet being the fruit of the oil-palm!  The palm-nut vulture does eat other foods as well, though, including crabs, fish, small mammals, reptiles, and birds.  Unlike most other vultures, rarely will a palm-nut vulture be spotted at a large carcass.

3.  The Egyptian vulture, much like the palm-nut vulture, also has a very varied diet.  This particular vulture also has ties to the lammergeier in the ways it gets to its food!  As is typical of vultures, the Egyptian will scavenge large carcasses, and this carrion is the primary component of its diet.  Just like the palm-nut, the Egyptian vulture will also consume rotting vegetables and fruits and, even grosser, it will eat poop!  (Although it may be gross, it is thought by many scientists today that part of the reason that so many people have allergies is because we don't eat poop!  Well....kind of.  Just read the post HERE.)  The Egyptian vulture also loves to eat eggs, but to get at the soft interior, the bird employs the use of tools, throwing rocks at the eggs to break them open!  To see a video of this, check out the YouTube link below!  But honestly, you might want to mute the video, the guy's voice is SOOOO annoying....

4.  Although this guy doesn't look quite as funky as some of the other vultures that we have already looked at, I really like the Cape griffon vulture (oftentimes simply called the Cape vulture, not to be confused with the griffon vulture) because I get to see them in the giraffe exhibit at the Cheyenne Mountain Zoo most times we go down!  I was unable to figure out what the scientific name of the Cape griffon vulture, Gyps coprotheres, means.  I found that the genus name, Gyps, means "Condor" in Greek, and I am thinking that the species name, coprotheres, might have something to do with poop, given the fact that the Greek root "copros" means dung or excrement (i.e. coprolites are fossil poop).  However, I couldn't find anything on the Internet that would either confirm or deny my assumptions, so instead of hearing about some fascinating aspect of the Cape griffon vulture's feces, you instead can view some pictures and a video that myself and Grace Albers took at the Cheyenne Mountain Zoo!

The video is indeed the link below, I didn't just accidentally upload two of the same picture!

5.  Finally: number 5, the last Old World Vulture on our Top Ten list!  Meet the white-headed vulture, aptly named due to the fact that it has a white head and it is a vulture.  The white-headed vulture is an early riser, often the first vulture to arrive at a carcass.  Because of this, it would have been funnier for me to put the white-headed vulture at the very top of this list, but I'm too lazy to change it so you will have to get by with me just telling you about how funny it is.  Often considered to be an "aloof" vulture (meaning that it generally sticks to the outskirts of a group of feeding vultures), the white-headed vulture can be very aggressive, rushing into the midst of a large group of vultures to grab a scrap of food, and then rushing right back out!

This concludes the first half of our "Top Ten Vulture" posts.  Check back soon for the second half, the New World Vultures half of the posts!

23-Fact Tuesday: Prairie Falcon, Red-Tailed Hawk, and Great-Horned Owl at the Dino Hotel in Denver!

As I mentioned in a post just a few days ago about the Harris hawk (which you can read by clicking HERE), the fantastic dinosaur-themed remodel at the Best Western Denver Southwest is well underway, and the folks over there are making the hotel even more fantastic by having weekly raptor (bird of prey) shows on Saturdays!  Each Saturday, Anne Price, one of the folks over at the Raptor Education Foundation, brings over four birds of prey to show to the audience!  Last week, they brought over a Harris hawk (which, like I already mentioned, I talked about in a previous post), a prairie falcon, a red-tailed hawk, and a great-horned owl!  I have so much information I wanted to share with you...but how!  How could I POSSIBLY share all of this information in a non-story like, brain-dumpy fashion?  AH-HAH!  Another 23-Fact Tuesday is upon us!  But before you enjoy, make sure you check out the website for the Raptor Education Foundation by clicking HERE, and checking out the Facebook page for the Best Western Denver Southwest by clicking HERE!

1.  This particular prairie falcon actually used to fly down at the Air Force Academy, where many of the cadets have the option of training a falcon!

One of the cadets with a falcon!  Photo Credit: www.usafa.af.mil

2.  The great-horned owl used to be the only member of the genus Bubo (what a fun name, right?), but around ten years ago, scientists reclassified the snowy owl to be the second member of the genus.

Quite possibly the most famous snowy owl of all time, Hedwig from the spectacular Harry Potter series!  Photo Credit: www.lauraerickson.com

3.  As for all raptors except for the New World vultures, the female red-tailed hawks are bigger than the males.

4. Falcons like the prairie falcon and the peregrine falcon will dive at their prey and actually punch them with their balled up feet!

A peregrine falcon diving to attack a brown pelican: holy COW!  Photo Credit: www.birderslibrary.com

5.  In response to this behavior on the part of the falcons, some prey species of bird have developed very tough feathers on their back and such to defend themselves against such attacks.

6. In nocturnal owls, like the great horned owl, the eyes are surrounded by a sort of sensory dish full of hyper-sensitive feathers that can actually detect sound, funneling it into the “dish.”

7.  Diurnal owls, such as the burrowing owls, do not have this dish, or at least it is not as pronounced as other owls that are more active at night. The burrowing owl is actually most active at dawn and dusk, although it can function perfectly well at night.  

A funny looking burrowing owl!  Photo Credit: animaluniquepictures.blogspot.com

8.  Red-tailed hawks apparently love to nest in cottonwood trees.  I think I might have actually found a red-tailed hawk nest in a cottonwood tree: hopefully, there will be more information on that in a later post!

A red-tailed hawk nest in what might or might not be a cottonwood tree....Photo Credit: gaiagarden.blogspot.com

9.  The great-horned owl that Anne brought in for the presentation is DEFINITELY a survivor: he has survived being shot, hit by a car, West Nile Virus, and being attacked by another owl!

10.  Here's the scoop: this particular great-horned owl first came to the sanctuary because it was hit by a car which, in the long run, probably saved its life. The reason why it hit the car in the first place was that it was flying drunkenly about due to the fact that it had West Nile Virus, which had caused its brain to go a little loopy. The owl received the medical treatment that it needed, and it wasn’t until a few years later, when it accidentally broke its leg, that a full X-Ray was ordered, and it was revealed that the owl had a few pellets lodged in its back. The skin had grown around it and completely healed, but yeah.  Still.  What a trooper!

11.  You might have noticed on some of these great-horned owl pictures that the pupil of the left eye is MUCH more dilated than the pupil on the right eye.  This is because this great-horned owl is blind is his left eye, due to the brush with West Nile Virus we were just talking about.

12.  Later on, there was an enclosure that contained three great horned owls: two males that could fly and an older, grumpier female that couldn’t really fly that well. The two males could EASILY avoid the female by remaining up in the top of the enclosure, where the female simply could not reach them. However, one time, the people walked into the enclosure to find this particular male great horned owl perched next to the grumpy female. The female didn’t seem to be displaying any hostility towards him, so they left them together.  After a few weeks, I believe, the female had decided that she had had enough, and attacked the male, and I believe broke his wing. He can fly today, but not terribly well, and not very far.

13.  Not all red-tailed hawks have a red tail. There is a wide variety of coloric differences across its vast range, and sometimes even melanistic forms are seen. This DEFINITELY messes with birders!

A melanistic red-tailed hawk!  Melanistic, FYI, would be just like a melanistic jaguar, where the coat of the animal is very, very dark, much darker than noraml, due to a pigment issue in its genes!  Photo Credit: thenatureniche.com

14.  As a matter of fact, none of them have red-tails their first year! At that point in their life, their tails are a darkish gray-brown: muddy and dull with darker brown stripes.

A juvenile red-tailed hawk!  Photo Credit: animals.nationalgeographic.com

15.  The juveniles don’t actually get their red tails until they molt, which, at the time this post is being written (early July) is happening now, in the spring and summer.  Here, we have a video featuring the red-tailed hawk, as well as a brief appearance by a pooping Harris hawk (which unfortunately happens off screen)!

16.  Besides the owls, only one other type of raptor is able to swivel one of it's toes to face backwards, so that it has two toes pointing forwards and two toes pointing backwards: the osprey!  The osprey does this to allow for a more secure grip when catching fish, and the owls undoubtedly do it for much the same purpose when it comes to holding on to their prey.

An osprey, where you have a clear shot of its feet!  Photo Credit: www.flickr.com

17.  This particular prairie falcon has also survived a brush with West Nile Virus, just like the great horned owl!  Anne was telling us that no one really but her would know it, but he far right tail feather on this bird has grown in weirdly ever since the birds dangerous brush with the virus.  Here, we have a brief video where Anne talks a bit about this particular falcon's feather!

18.  Just like dogs, birds don't sweat.  Also just like dogs, birds will sometimes pant to help keep cool!  Below, we have a video of the great-horned owl thermoregulating via something we like to call "gular fluttering!"  

19.  As you can see in this video below, the prairie falcon is being assisted in its thermoregulation by the presenter Anne, who is misting him with some water!

20. The great-horned owl will eat (amongst other things, no doubt) worms, insects, fish, any amphibian, any reptile including rattlesnakes, scorpions, tarantulas, porcupines, skunks, raccoons, and other raptors.

A great-horned owl with a snake!  Photo Credit: www.flickr.com

21.  The two brown streaks under its eyes help keep some of the light from reflecting into its eyes, just like the black paint worn under the eyes by football and baseball players.  Another fascinating example of convergent evolution at its finest!

Convergent evolution at its finest!  Photo Credit: www.stripes.com

22.  A lot of the time when people think a hawk has gotten in and killed their chickens, its actually an owl.

A fox in the henhouse!  I couldn't find a picture of a hawk in a henhouse, and besides, I really liked this picture.  Photo Credit: www.hyscience.com

23.  For reasons that Anne couldn’t fully explain, other than maybe panic or opportunity, often when an owl finds itself in a pigeon loft, the owl will only pull out and eat one or two of the pigeons, but it will pull off the heads of almost all of them, and leave them there.  An interesting and gruesome way to end yet another fun-filled and fascinating 23-Fact Tuesday!  

And that's why people often use fake owls to scare away pigeons!  Photo Credit: loomofruin.blogspot.com

Make sure you check out the website for the Raptor Education Foundation by clicking HERE, and checking out the Facebook page for the Best Western Denver Southwest by clicking HERE!

Animal of the Day: Viscacha

Today's Animal of the Day is the viscacha and, in my opinion, the viscacha is one of the cutest animals in the world!  There are five species of extant (still living, opposite of extinct) viscacha, composing two genera.  The viscachas live in the South American Andes, with one species, the plains viscacha, inhabiting the Pampas of Argentina.  The plains viscacha can apparently live in warrens (groups of interconnected burrows) of up to around one hundred individuals!  

Now what exactly is the viscacha, anyways?  Except for the long tail, it sure looks like a rabbit, now, doesn't it?  Well, the rabbit-like features of the viscacha actually evolved through a fascinating biological process called convergent evolution, in which organisms evolve a similar adaptation to other organisms, but did not receive the adaptation from a common ancestor.  For example, the antlers of the elk and the moose are not an example of convergent evolution, as the common ancestor of the two animals both had antlers.  

However, the saber-teeth in the Chinese water deer and the musk deer DID evolve via convergent evolution, as their common ancestor did not have these features.  And yes, that picture of the Chinese water deer to the right is a real picture.  We'll talk about these fascinating animals at some point in the future.  

Tangents aside, I never actually answered the question: what are the viscachas related to, if not rabbits?  Rabbits, along with hares and pikas, are members of the order Lagomorpha, or the lagomorphs, contrary to the belief of many people, who (understandably) think that the rabbits are actually rodents.  If you were to say that the viscacha was a rodent, however, then you would be correct!  The viscacha is indeed a member of the order Rodentia, and are fairly closely related to the chinchillas, one of which is pictured off to the left.  The chinchillas, just like the viscachas, are also native to the South American Andes.  The chinchillas, despite being a very popular pet (I remember my preschool had one when I went there), are not doing too hot in the wild: both extant species, the short- and long-tailed chinchilla, are labeled as "Critically Endangered" by the IUCN.  

This was the birthday post of Isabel Lippincott! Happy birthday, Isabel! If you have a birthday coming up, just email me the date at cuyvaldar123946@gmail.com with the date and your favorite animals, and I will do my best to get a post in! And if you like what you are reading, please feel free to follow us here or via Facebook!

When Is A Turtle Not A Turtle?

When it's a placodont!  All right, so they're technically not turtles.  Instead, they are a classic example of the fascinating phenomenon known as "convergent evolution," as we shall soon see!

Placodonts were a fascinating group of marine reptiles that lived during the Triassic Period in the Mesozoic Era, between around 235 and 200 million years ago (MYA), and thought to have a common ancestor with the long-necked plesiosaurs and the long-necked nothosaurs, all of which are in the large group called the saruopterygians.  As a group, the placodonts are sometimes referred to as "walrus turtles," due to their diet of molluscs and other shelled invertebrates and, of course, their general appearance.

Like the turtles and tortoises of today, the placodonts would not have been all that quick and nimble.  Their weight would have made them negatively buoyant, akin to the manatees and sea cows of today, meaning that they would have had no trouble swimming along the bottom of the ocean, snapping up molluscs and other shelled invertebrates, and using their large, flattened cheek and palatal teeth to crush them down.  It's also possible that they scraped algae off of marine rocks and swallowed it whole, letting it slowly digest in their massive guts!  Like modern sea turtles, the placodonts are thought to have been amphibious, spending most of  their time (sleeping, chillaxing, and other activities) on land, but dipping into the water to feed, akin to the extant marine iguana of the Galápagos Islands.

Although younger placodonts would have been especially vulnerable to predation from many different types of animals, many paleontologists puzzle over why the ponderous adult placodonts would have needed this armor, as there don't seem to be any marine predators capable of making a meal out of them that lived at the same time.  Of course, as we mentioned before, they probably spent much of their time on land and, as we also mentioned before, their awkward build would have left them particularly vulnerable to attack.  So to counter this, some of the placodonts started to evolve in a very turtle-like appearance. 

Placodus, the animal whose name is lent to the entire group, displays a single row of dermal ossifications above its neural spines down its back.  This dermal armor (a fancy way of saying "skin armor," in which the skin hardens into an armor like structure, as seen in the armadillo) would have helped to protect the animal from attack.  Earlier, more primitive genera, such as Paraplacodus, lack this dermal ossification.  However, other, more derived placodonts take this ossification of the dermals to a whole new level.

Remember Henodus, the first picture in this post? Henodus is one of those dermal armorers (I don't think that's actually a word) that took the ossification of the dermals to a whole new level.  Outwardly similar to the turtle shell, the placodont armor was composed of a number of polygonal ossicles, while the shells of turtles are composed of large plates.  Two other placodonts that were extremely well armored include Cyamodus, as well as the VERY turtle-looking creature, Placochelys. 

Like many other animals, the placodonts became extinct at the end of the Triassic Period.  Many groups did survive, however, and one of those groups that survived through to the Jurassic Period was actually the turtles!  220 MYA, the placodonts were sharing the seas with what would one day become the hard-shelled reptiles adored by so many people! 

This is the birthday post of Darlene Neher!  Happy birthday, Auntie Dar!  If you like what you are reading, please feel free to follow us here or via Facebook!  And remember, if you have a birthday coming up, just email me the date at cuyvaldar123946@gmail.com with the date and your favorite animal, and I will do my best to get a post in!

Animal Questions #1: Jurassic Park Reality, Sea Otter Hand Holding, and the Great Auk Extinction

So I've started a new video series in which I answer questions about animals that you guys have.  I finished Episode 1 today, and if you click on the link below you can watch it, too!

CLICK HERE TO LEARN THE ANSWERS.

I decided I would also write out the questions and answers here, just in case some of you would rather read the questions and answers, instead!  So here they are, in all of their glory and splendor!

1. Could people actually clone dinosaurs and make a real life Jurassic Park?

Ever since the fantastic book Jurassic Park came out in 1990, people started to wonder: could this actually happen? Could we actually bring dinosaurs to life via the miracle of cloning? Following the release of the movie in 1993, the idea was on the mind of even more people. Sadly, (or perhaps fortunately), from what we understand about DNA at this point, we simply cannot clone dinosaurs, not even by using mosquitos trapped in amber. DNA is a very fragile molecule, and does not take all that long to break down. Sure, mammoth mummies frozen in the permafrost in Siberia have successfully yielded DNA. Mammoths, however, only went extinct several thousand years ago. From a geological standpoint, mammoths, you and I lived practically at the same time as each other, when compared to how long ago the dinosaurs roamed the earth. Furthermore, the permafrost has acted as a freezer, helping to preserve the DNA in ideal conditions for scientists to extract it from the mammoth at a later date. So to sum up? To the best of our knowledge, Jurassic Park: not happening. However, Pleistocene or Ice Age Park may not be all that far off!

2. Why do sea otters hold hands while they’re sleeping?

Sea otters often do this to keep themselves from drifting apart from other sea otters. Although adult sea otters generally forage for food by themselves, they will often form large groups, called “rafts,” sometimes numbering as many as 2,000 individuals. When in these rafts, to avoid floating apart from each other, they will sometimes hold hands. They will also sometimes tie themselves to kelp when they are sleeping or feeding to keep from floating away, as well.

3. Why did the great auk go extinct?

For those of you who are unfamiliar with the great auk (Pinguinus impennis), this penguin-like creature (a product of convergent evolution) inhabited the North Atlantic Ocean in the Northern Hemisphere, and became extinct mid-way through the 1800s. The great auk was intensely hunted by humans in European waters for their down feathers, (which were actually used in both pillows and hats), as well as for food. (Not the down feathers, mind you, but the meat of the bird and its eggs). It wasn't until 1553, around the time that the nesting sites of the great auk had been all but eliminated on the European side of the Atlantic, that the great auk first became officially protected. In 1775, people who had broken a law forbidding people from killing the great auk for its feathers were actually beaten publicly! Following the local extinction of the great auk in Greenland in 1815, the sole remaining breeding site of the great auk was a small, volcanic island. Off of the coast of Iceland, the island was dubbed "Geirfuglasker," after the Norse term for "great auk," "Geirfugl." In 1830, however, the great auk population on Geirfuglasker came under siege by two elemental forces that it had no hopes of combating: an underwater volcanic eruption and a subsequent earthquake, which combined to destroy the island, terminating most of the rest of the great auks. That’s not to say that the volcanic eruption and volcano are to blame: humanity definitely takes the bullet for that one.

If you have any questions yourself, ask me here at the blog, email me at cuyvaldar123946@gmail.com, comment below the video, or tweet them at me @TNaturalWorld1. Thanks for watching/reading/whatever you did!