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:

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!

The Animal Statues of Brookgreen Gardens

Brookgreen Gardens near Myrtle Beach in South Carolina was a fantastic place to visit.  They had something for everyone, from a zoo, amazing flowers, a butterfly garden, and some amazing statues!  Today, I'm going to share some pictures of the cool animal statues with you, taken by my mother and I!  Enjoy!

A pair of jaguars attacking a tapir!

A pair of bears!  Photo Credit Julie Neher

A pair of bears!  Photo Credit Julie Neher

A pair of bears!  Photo Credit Julie Neher

  A regal looking lion!  Photo Credit Julie Neher

What look like a king penguin and a pelican

A pair of chortling penguins

What looks like a stork and a shoe-bill

Some people using giant tortoises as a means of transportation!  Photo Credit Julie Neher

This just looked really cool

Platypus

Bessie the Belligerent!

A giant anteater.  Photo Credit Julie Neher

A mammoth

A mastodon

Afterdeck on Dwellable

Squirrel Footprints on Our Doorstep!

This morning we woke up to a fresh blanket of snow, the first (real) snow of the year for us!  Naturally this means that I must do all of my first snow traditions, including watching the Battle of Hoth scene from Star Wars Episode V: The Empire Strikes Back, and wearing my Mammoth and Mastodon Madness t-shirt from the Denver Museum of Nature and Science.  Anyways, on my way over to school, I saw a few footprints.  I took a few pictures on my phone so they aren't very good looking, but I believe them to be from the eastern fox squirrel, the type of squirrel that is just so common around here in Boulder, Colorado!  If anyone knows otherwise please let me know, but I am 99.99% sure that this is what we are looking at!  The first two pictures are the ones that I took with my phone.  The first picture has an impression of my right index finger in the snow next to the footprints for scale.  The third picture is a picture that someone else took of some eastern fox squirrel footprints in the snow too!

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!

Animals of South Dakota: Part 1

Hypothetically, let's say that you are taking a trip up to South Dakota from where I live in Boulder, Colorado, much like my family did nine years ago, in 2003.  You might be thinking "Ew, South Dakota?  What's there to do there?"  Well, although much of the driving might be boring, there are most definitely a few cool places to stop, as well as cool animals to watch for on the way!  Let's start with the sites.

1. The Mammoth Site - This is one of my all time favorite Ice Age sites, about 40 minutes south of Custer.  According to their website, "To date 60 mammoths (57 Columbian and 3 woolly) have been discovered as well as 85 other species of animals, plants, and several unidentified insects."  This place is very interesting, and not just to those of my ilk.  Most recently, they have added a replica of the frozen baby mammoth discovered in Siberia named "Lyuba." - http://www.mammothsite.com/
   

   

   My sister and I standing next to a Columbian Mammoth cutout at The Mammoth Site

Part of The Mammoth Site

2.  Badlands Petrified Garden - I do not remember if we went to this place, but it definitely looks cool.  It is right around the Badlands National Park.  - http://www.badlandspetrifiedgardens.com/

3.  Reptile Gardens - On the way to the Badlands National Park in Rapid City, we have the awesome Reptile Gardens, which I know for a fact that I have been to as we have pictures of my sister and I next to a couple of massive tortoises.  However, our scanner stopped working, so all I have is this picture of a guy pulling a Steve Irwin-like stunt.  Definitely worth the admission price. - http://www.reptilegardens.com/

4.  Bear Country USA - Also on the way to the Badlands National Park, and just a bit farther than the Reptile Gardens, and also in Rapid City, is Bear Country USA.  I have not been there, but my parents have in I believe 1991.  They said that it is a really cool place, where (surprise surprise) you get to see a bunch of bears.  So that should be exciting! - http://www.bearcountryusa.com/

Custer on Dwellable