22 November 2014

What Is on Your Nose?

Menodus (junior synonym to Megacerops),
Field Museum, Chicago.
Megacerops has a pair of horn-like protuberances on the rostral end of the skull. In the mounted specimen from the Field Museum, shown here, those protuberances appear smaller than they are often illustrated. The nostrils do not appear, in this specimen, to be completely formed as external foramina, as one would expect. The nares are actually present in the concavity ventral to the the twin horns of the face. The nasal bones appear to extend over the premaxillae between the horns but do not recurve to meet the premaxillae at the chin. As expected in the list of rhinoceros-like traits, the optic foramina are small, relative to the entire skull, and offset laterally so that the animal most likely did not have a great deal of binocular vision. Not having depth perception, we can probably safely surmise that Megacerops was not adept at detecting predators visually. To make up for that deficit we can assume that the powers of smell and hearing may have been more sensitive in Megacerops (there may be more definitive answers that I have not found quite yet). Conversely, mixed herds and even the addition of non-mammalian (i.e. bird) members of the community may have aided in predator awareness, meaning that none of the senses would have had to have been highly adapted toward sensing predators. Either way, the horns on the face of Megacerops are not used for the purpose of combat primarily. As skeletal elements, a broken horn would be tremendously detrimental to the health of the animal. Such a danger would cause the animals to use their horns, both males and females possessed them, as a last resort in protecting themselves. The horns would have served to intimidate as much as the sheer size of the animal itself.

21 November 2014

Rhinos or Horses?

Though not a rhinoceros and much more closely related to horses, Megacerops was a very rhinoceros-like relative of horses and is therefore a bit confusing on first glance. Known more popularly as Brontotherium, Megacerops Leidy 1870 was far larger than any modern horse or rhinoceros. Its distinctive look, two large bony protuberances above its nose, make it look slightly more like a rhinoceros, but are significantly different from any known rhinoceros horn as well. The use of these protuberances is well documented, as we shall discuss. This animal is yet another North American Eocene mammal.
Robert Bruce Horsfall, 1913

20 November 2014

Star of the Show

After having more than a few handfuls of information written about Paraceratherium and an entire episode of the Walking With Series about one of them, this magnificently large mammal has certainly shown that it has a great deal of popular culture credit. The animal has been shown in video games as well, particularly where it can be modded in, like in Zoo Tycoon 2. It has also shown up in a non-modded form in Jurassic Park Builder as well, to be fair, as a Glacier Park animal. In both games it is seen under the popularized name Indricotherium. There are toys out there, but I would stress caution with buying them under the impression that they are accurate models. Many of the toy images I have seen show extremely muscular giraffe-like animals or emaciated camel-like animals. Considering all of the attention that this animal has received in the last decade, it is very difficult to figure out why the toy models are so ridiculously off base.

19 November 2014

What About That Head?

The head of Paraceratherium on the cover of that book yesterday got me thinking. What does the head of a giant rhinoceros ancestor look like exactly? Is it fantastical to have elephantine ears? The simple answer is that we will never really know and artistic license can do whatever it wants to the head. The fact that the illustrator of that book cover went with the head design he did, maybe at the behest of Donald Prothero, only backs up that point. To be fully honest though, that idea is much more innovative than the rhino-on-a-giraffe-neck design that is typically depicted. There is nothing wrong with the usual interpretation because it is usually aligned to the paleontological interpretation of the skull, but with the ears not being preserved on any specimens, to my knowledge, and they could have looked like anything. The open mouth and down-turned lip is sort of mandatory, because of the skull, so the interpretation of that does not often change. Regardless of whether you liked it or not, the new and old interpretations both have merits and you have to admit the idea of a rhinoceros head on a giraffe sized neck is interesting. Seriously though, look at that rhino head on a giraffe neck!
Paraceratherium herd: Elizabeth Rungius Fulda 1923

18 November 2014

A Tome of Knowledge

I love original descriptions. That has probably been said many times over. I hate when they are not available for free to anyone and everyone (because it is hard to get articles for some of our younger readers). Despite that happening, there is an absolute mountain of work out there on Paraceratherium. This is due in part to the fact that there are more than a handful of junior synonyms for this animal, meaning that there are a fair number of initial description papers for these now dubious names. There are also new remains still being discovered and described under the currently accepted generic name as well. Rather than listing out hundreds of papers today though, I am encouraging the audience to instead check out, inter-library loan, or even buy a book! This is not because I love mammal paleontology or specifically the work of the author (though anyone into fossil mammals knows the name Prothero), but because anyone that is really interested in Paraceratherium and its family would enjoy and get a lot from Donald Prothero's book Rhinoceros Giants: The Paleobiology of Indricotheres. The first link to the book is a Google powered preview, but this link right here goes to the Indiana University Press. Why would I encourage anyone to buy directly from the publisher instead of shopping around (assuming that purchasing is the intent)? The answer is actually a matter of savings. The publisher is offering the book electronically for $8 less. I love the smell and feel of a new book (almost as much as an old book), but sometimes less is more. You can carry an electronic copy more easily as well. Regardless, I cannot say I have read through this entire book, but the reviews I have seen and the snippets I have previewed point to it being part historical, mostly technical, but very informative overall. As a collector of subject literature (e.g. I get books about birds and dinosaurs whenever I can to compare the information presented regardless of author) I have to say, even if you do not agree with the author, this is a comprehensive work on the animals we have been discussing all week and well worth the investigation on your part! Plus, check out the head on the Paraceratherium on the cover. Pure gold!

17 November 2014

See the Models

All of the instances of Paraceratherium are well exhibited in this short video. There is not much to really say about it, but watch this one. The entire episode, if that is more interesting to folks out there, is available here on EntireDocumentaries.

16 November 2014

Teach That Memo

Most of the time when a name changes it takes a few years for the internet and sometimes even technical literature to adopt, accept, and print that change. Some of the pages of facts for younger readers today never changed their information and still list animals under their junior synonyms like Indricotherium and Baluchitherium. Any way you pull them apart though, these are all the same animal, Paraceratherium. Enchanted Learning is the biggest offender in that regard, but if one were to go through all of the synonymous names and read the descriptions there would be a wealth of information at their hands. About and the BBC have their naming conventions better put together than Enchanted Learning does however, which is a bit nicer and vastly more convenient. The BBC, of course, uses stills and information from the Walking With Series while About does an even shorter version of what we take all week to do here; integrating technical science and popular sources as much as possible to make the information readable.