Top Ten Mammals That Look Like Something They Aren't (Part 2)

Here is Part 2 of this duo of posts.  For Part 1, click HERE.  What are these two posts about?  Well, we are going to be taking a "Top Ten" look at some mammals that look a lot like something they aren't.  Sometimes, these two animals are fairly closely related: other times, they are quite far apart!  All of these examples will be results of a fascinating phenomenon known as "Convergent Evolution," which is where similar ecological and environmental factors cause two very different animals to evolve in a similar fashion.  So let's dive right in!  But first, this is the birthday post of Joseph Kleinkopf, happy birthday Joseph!

5.  Civets and genets - These two groups of animals are quite possibly some of the most unknown animals that are around today.  Members of the family Viverridae in the order Carnivora, if someone does in fact see one, they usually just assume that they are cats, dogs, or something else along those lines.  The family that the viverrids are most closely related to are, in fact, the cats, but they are also related to they hyenas and the mongooses.

4.  Maned Wolf - The maned wolf is neither a wolf, as its name implies, or a fox, as its outward appearance would indicate.  It is related to both, and is in the family Canidae (the dog family) just like wolves and foxes, but it is thought to be most closely related to the South American bush dog.  Interestingly, although small vertebrate prey is quite important to the maned wolf, it eats a great deal of fruits and vegetables, with the most frequently consumed fruit called the wolf apple.

A slightly fuzzy picture of a brown-morph black bear right outside of our tent-cabin in Yosemite!  Photo Credit: Julie Neher

3.  Black Bear - When it comes to the names of the three bears that inhabit North America, they can be very misleading indeed.  ESPECIALLY the black bear, for the black bear, like many other animals throughout the world (including, of course, humans), has different color morphs.  The black bear is, of course, most frequently black.  However, some of the time, the black bear is actually brown, or cinnamon colored, which is not to be confused with the ACTUAL brown bear (or grizzly bear).  In Alaska and northwest Canada, there is the "glacier" color morph, a grey-blue phase.  But I think my favorite is the "Kermode" color phase, which is exclusive to the coast of British Columbia.  This bear is a creamy-white color, and looks a heck of a lot like the polar bear!  How very, very confusing!

2.  Thylacosmilus - Over the course of mammalian evolution, the marsupials have spat out a large number of look-alikes, or animals that evolved via convergent evolution to appear a great deal like other animals throughout the world.  One of the most amazing of all of these (by far, in my opinion) is Thylacosmilus, a marsupial carnivore from the Miocene and Pliocene Epochs of South America.  Thylacosmilus convergently evolved to resemble the saber-toothed cats of North America.  Unfortunately, following the creation of the Isthmus of Panama that connected North and South America around 2 MYA, the saber-toothed cats like Smilodon moved down the newly-formed land bridge to colonize South America during the Great American Interchange, outcompeting Thylacosmilus in the process.

1.  Raccoon Dog - The raccoon dog is a fantastic case of an animal that is now that it appears to be.  You take one look at it, and you decide conclusively that you are looking at a raccoon, no doubt about it.  Your second and third takes yield the same result.  However, the raccoon dog is not a raccoon, as both its name and appearance might indicate: its a canid, through and through!  Listed as "Least Concern" by the IUCN, the raccoon dog is native to eastern Asia, and is not very closely related to any extant species of dog.  Just a tip, if you are trying to make someone look foolish, showing them a picture of a raccoon dog and having them guess what animal it is is an excellent way to show off your animal-prowess.  Unless they know what it is, in which case you will be the more foolish.

Thanks for joining us tonight for our top ten list!  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! 

Convergent Evolution: Hesperornis and Penguins

Everyone who is reading this blog, and most people who aren't, have heard of penguins, and know, more or less, what they look like.  However, most people have no idea what a Hesperornis is, which is entirely forgivable.  What is especially interesting about Hesperornis is that it was really the "original penguin," in the loosest sense of the terms.

If not for the captions below each picture, these two animals would most likely be quite difficult to tell apart.  One major difference between the two birds is in the mouth: Hesperornis had teeth, a feature which no modern birds possesses.  Another major, but non-skeletal difference, between the two birds is that Hesperornis died out 78 MYA, during the Late Cretaceous.  Its remains have been found in the United States (Kansas), Canada, and Russia.

The similarities between Hesperornis and modern day penguins is called "Convergent Evolution," a fascinating topic which we will undoubtedly touch upon numerous times.  According to Science Daily, convergent evolution is, "In evolutionary biology, convergent evolution is the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches."  In English, when two animals, not necessarily closely related at all, evolve similar features that serve the same purpose.

An (excellent) drawing of the skull of Thylacosmilus

 Another example which we have already talked about is the long, saber-like canines that evolved in both the saber-toothed cats, such as Smilodon, and the South American marsupial carnivore Thylacosmilus.

 This post is part of the "Convergent Evolution" series.  For the rest of the posts in this series, click HERE.

Smilodon Vs. Thylacosmilus: The Saber-Toothed Marsupial

Two million years ago, a saber-toothed predator stalked the landscape of South America.  Possessed with long, dagger-like teeth, Thylacosmilus was undoubtedly a terrifying predator of the plains of Patagonia.  This saber-toothed predator would have given even the saber-toothed cats pause, despite the fact that (to paraphrase Obi-Wan Kenobi), "He's more kangaroo now than cat."  Despite superficial similarities, Thylacosmilus was not a saber-toothed cat.  Instead, it was a six foot long, 500 pound saber-toothed marsupial.

A reconstruction of Thylacosmilus by the talented young artist Sam Lippincott.  Interestingly, the super-sized canines of Thylacosmilus grew continually throughout its life, unlike those of Smilodon or Xenosmilus (see below), two of the actual saber-toothed cats.  Photo Credit: Sam Lippincott

The immense canines possessed by Thylacosmilus had previously evolved in both the cat-like Nimravids and the various saber-toothed cats (amongst others), and is a classic example of convergent evolution, a topic, in my opinion, that is one of the most interesting happenstances in nature.  We will hopefully talk about convergent evolution sometime next week.

A mounted skeleton of Xenosmilus, a type of saber-toothed feline, at the Mace Brown Museum of Natural History at the College of Charleston in South Carolina.  I got to visit here in July of 2014, and it was a very nice little museum.  Compare the skull of Xenosmilus with that of Thylacosmilus (below).

Anyways, Thylacosmilus lived during the Miocene and the Pliocene Epochs, from 10-2 MYA.  Up until 2 MYA, South America had been its own, separate land mass, not connected to any other continents since some time during the Cretaceous.  2 MYA, however, something extraordinary happened: the Isthmus of Panama was formed, connecting the two continents.  With this connection, came something scientists have dubbed the "Great American Interchange."  Animals from both continents could move, and spread out into the other continents.  For some creatures, like the saber-toothed cats, this was a good thing; they moved down into South America from North America and dominated the landscape.  For other predators, like the terror-bird Titanis(again, a topic for another time), it was good, for a while; after moving into the southern part of North America, however, Titanis was outcompeted by other predators.  For Thylacosmilus, it was down-right disastrous.  Shortly after the Great American Interchange, fossil evidence of Thylacosmilus entirely disappears, similar to the competition between the dingo and the thylacine that drove the thylacine to extinction on mainland Australia.

The skull of Thylacosmilus on display at the American Museum of Natural History in New York.  Got to see this sucker in person in August 2014, when I visited with my good buddy Zach Evens! 

This is a partial post for the "Convergent Evolution" series.  That means that this post is partially included, but was not made specifically to be a part of that series.  HERE is a link to the Homebase for this series.