ROUS (RODENTS OF UNUSUAL SIZE) DO EXIST – THEM BONES – PALEONTOLOGY

Fans of “The Princess Bride” will know instantly what this post is about – but for others, just follow along.  In the next of the series of paleontology posts (I think i will be updating this site soon to categorize my musings, since they do go off in very different directions) I would like to talk about an announcement made last week about an exciting discovery in Madagascar.  What makes this so thrilling is threefold:

1) it documents that the mammals that existed during the Upper Cretaceous period between 72 million and 66 million years ago were a great deal larger than originally thought

2) its findings helped to fill in a previously blank section of the evolutionary tree and

3) it proves that William Goldman, the author of “The Princess Bride, was an auger and visionary.  In fact the details about this  unearthing of a new mammal reads like some sci-fi fantasy. Let me elucidate.

At the time this creature lived, Madagascar was actually part of a giant supercontinent land mass called Gondwana that incorporated what  we know today as Africa, South America, Arabia, Madagascar, India, Australia and Antarctica.  The area was designated Gondwana  by an Austrian scientist named Eduard Seuss  – not a relation to  Dr. Seuss whose actual last name was Geisel,  but this appellation does sound like it came from Seuss’ “Oh, The Places You’ll Go.”  Despite my fancy,  Gondwana is a region in Central India which has topographical similarities to Southern Hemisphere continents.  Here’s a simple map that shows the evolution of the continents:

 

pangea

 

Here is some finer detail on the continents-to-be:

136146-004-CD208F62  TRIASSIC

 

136145-004-C056A7FB JURASSIC

Madagascar today is an island off Africa in the Indian Ocean:

map

 

The formation of Madagascar into an island was completed about 188 million years ago, between the Triassic and Jurassic periods.  This is significant, as you will read in a moment but first, without any more delay – let me introduce you to today’s subject:

Vintana Sertichi.  

85571_990x742-cb1415195495

I know, this is a little vague.  Try this reconstruction:

image_2256_2-Vintana-sertichi

 

Frontal view:

IMG_0587

 

 

The name is in itself a fascinating insight into  the mysterious world of paleontology : “Sertichi” comes from Joe Sertich, a graduate student who was at a Madagascar dig with professor and vertebrate paleontologist David Krause of Stony Brook University of New York City. Sertich brought back a 150 pound slab of sandstone to New York, not knowing that a skull was imbedded deep within. This is not unusual – we had been told during my visit to the Paleontology lab of the Museum of Natural History that many of their specimens were not immediately identified but rather stayed safe in their plaster -cocooned  pods until a particular inquiry was made.  You can read about that in this post here.  Once in the lab, a CT-scan identified the fossilized skull.  “Vintana?” That’s Malagasy word for LUCK!

Now let’s go back to the geological importance of Madagascar’s island status.   It appears that our new friend Vintana Sertichi while looking like an overgrown groundhog, had some rather startling characteristics. Some of its features resemble reptiles that have been found previously on the mainland of Africa.  It’s teeth, however were more in tune with other herbivore mammals of the time. And, to make VS even stranger, some of its features were unique, suggesting an isolated evolution that would exist on an island.  For example, the orientation of VS’s brain pan tilts at a strange angle and it has huge cheekbones suggesting very powerful jaw muscles.  VS also had an enormous sense of smell as evidenced by its brain’s olfactory section occupying 14% of the total brain volume (human olfactory section,  in comparison is only .01%, while a dog’s is .31%.  In addition, VS’s ear canals appear to provide high-frequency hearing, and it also had extra-large eye sockets suggesting sharp sight even in low light. Super Mammal!  Seriously, the characteristics of VS are so unique that scientists believe it is a new genus (a class, or category of biological classification ranking between the family and the species). This find is also  extremely rare as only two much smaller  mammal skulls have been found to date in the Southern Hemisphere from the age of dinosaurs

However, there is still much to learn about Vintana Sertichi.  Without a complete skeleton, there is no way to ascertain other characteristics.   For example, did it lay eggs like other reptiles or have live births like  mammals – or was it more marsupial in its gestation?  Where did VS live – on the ground, in a burrow or up in a tree? Or, like the theatrical ROUS, did it live in a fire swamp?  Only time will tell if William Goldman was right.

rous

 

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